Big bore bullets: Part 1

by Tom Gaylord, The Godfather of Airguns™
Writing as B.B. Pelletier

This report covers:

• What’s a big bore airgun?
• Hydrostatic shock
• Back to airguns
• Why, then, the great debate?
• What’s ahead?

What’s a big bore airgun?
While there’s no official definition, those of us who talk about airguns call .177, .20, .22 and .25 calibers the smallbore airgun calibers. From that, you can deduce that anything larger than .25 caliber is a big bore. A few years ago, there was actually a heated debate over this threshold, when a rifle made by the late Jack Haley in .257 caliber competed in and won the last LASSO big bore competition held in Texas. I hope to show in this report why that debate was so heated.

pellets and bullets
From the left are the 4 smallbore calibers — .177, .20, .22 and .25. The jacketed bullet is approximately what the .257 Haley rifle shot, so even though it’s also a .25, it’s quite a bit larger than any pellet. Next to that, a 405-grain .458 bullet dwarfs everything.

To understand why the definition of a big bore is so important, you first have to understand how big bore airguns differ from most firearms that you may be familiar with. When firearms used black powder, there was substantially no great difference between a large bore airgun and a firearm. Sure, firearm bullets travelled more than twice as fast as airgun bullets when they left the muzzle, but all that did was shorten the range at which airguns were effective. In those days, all a bullet did to an animal was penetrate and create a wound channel through which blood was lost. It was important, therefore, to hit a vital organ to dispatch the animal with certainty.

And animals did not fall over when hit with bullets in those days. They usually stood their ground for several minutes until blood loss took its toll. It was much like hunting with arrows, only more effective because the bullets penetrated deeper and also went much farther with accuracy. A bowman might take a deer at 50 yards if he was a good shot — a rifleman could take one out to 200 yards if he was so inclined.

Once hit, it did not matter what gun sent the bullet, as long as the penetration was adequate and the vital organs were hit. What I’m saying is that a 45-70 buffalo rifle bullet is no more effective on a deer or bison than the same lead bullet fired from a .458 air rifle that develops only 500 foot-pounds at the muzzle. True, the hunter can shoot farther with the buffalo rifle, but their bullets are equally effective as airgun bullets.

Hydrostatic shock
Hunting with firearms changed forever at the beginning of the 20th century. Savage’s 250/3000 (also called the .250 Savage), created in 1915, was the first commercial bullet to leave the muzzle at 3,000 f.p.s. That was an 87-grain .257-caliber bullet. When that happened, the .25-caliber centerfire rifle went from being adequate for squirrels through fox to taking deer at 250 yards with certainty. It changed everything, because the new high-velocity bullets produced hydrostatic shock in the game.

You have probably seen slow-motion videos of a high-velocity bullet expanding in ballistic gelatin. As the bullet impacts the soft substance, it transmits a large portion of its energy in the form of a shock wave that travels through the liquid inside the target. In animal tissue, this shock wave hits nerves and causes them to transmit disruptive signals to the brain that shut down the animal’s life support. For this reason, a 50-grain .22-caliber bullet that impacts a deer-sized animal at 2,500 f.p.s. can actually knock that animal down on the spot, while a 400-grain bullet from a .45-70 that impacts at 1,000 f.p.s. will slip right through and exit the animal, leaving less than a quarter of its energy behind. The slow-moving bullet has to connect with vitals to do its job, while the lighter high-velocity bullet gets a boost from the shock it creates. Hunters of old were aware of this and knew they had to hit certain places on each animal to have an effect. They never gave it a second thought. But once hydrostatic shock entered the equation, the game changed forever.

Now, don’t get confused and think that faster pellets can do the same thing! Airguns top out at less than 1,500 f.p.s., so they can never produce hydrostatic shock in game. You need centerfire rifle velocities for that (above 2,000 f.p.s.).

Back to airguns
No airgun will ever get a bullet or pellet going fast enough to create hydrostatic shock. That is a fact of the physical world that we have to come to grips with. So, all airgun hunting, and especially big bore hunting, has to be done exactly as hunters did it in the 1870s. Shoot for the vitals and be prepared to wait for the bullet to do its job.

In this vein, we’re interested in the bullets that are shot by big bore airguns. What we need are 2 things — accuracy and penetration. Accuracy good enough to hit the vital areas on the game we’re hunting, and penetration adequate to go deep enough to pass through those vitals. Now — prepare to be shocked.

A 405-grain bullet from a Quackenbush .458 rifle will pass entirely through a 1,500-lb. American bison when it hits from the side. I say that because it’s been done — several times, in fact. I’ve seen several medium-sized animals (250-400 lbs.) hit with smaller big bore bullets that completely exited the animal. So, the thing you want to do is try to match the bullet to the intended target. A bullet that’s sized .458 is the same diameter regardless of whether it weighs 193 grains or 510 grains. The hole it leaves will be identical. But the depth of penetration won’t!

bullets
All these bullets are .458 caliber, but they vary greatly in weight. From the left they are: 193 grains, 350 grains, 405 grain and 510 grains.

bison
Stephan Bowles (right) dropped this bison with a .458 Quackenbush rifle. The bullets went completely through the animal from over 50 yards. He was guided by Eric Henderson. Henderson photo.

Why, then, the great debate?
This is why there was such a debate over the Haley rifle in .257 caliber. It was certainly capable of hitting the half-sized goat silhouettes out at 300 yards (the Haley hit them every time), but was it able to deliver a knockout punch on a goat-sized animal at that distance? Ballistics suggest, no — it wasn’t. While the 90-grain bullet might hit and even penetrate a game animal at that range, the entrance hole would be too small and the penetration too shallow to matter. Don’t get me wrong — I would not want to be hit by such a bullet at that distance! But it would have less energy than a .22 long rifle bullet has at 50 yards. So, it would not be a good choice for a reliable bullet on 150-200 lb. game.

What’s ahead?
In this series, we’ll discuss the various aspects of big bore bullets and the guns that shoot them. We’ll look at accuracy, bullet weight and length, lead alloys and other pieces of the big bore puzzle. This would be a wonderful time for you to ask any questions you may have.

159 thoughts on “Big bore bullets: Part 1

  1. G’day BB,
    If the slower bullet (air rifle) hit a substantial bone surely it would not break it as a good as the faster bullet (black powder) weighing the same weight?
    Bows, well they were knocking armored knights off horses at 200 yards plus if you believe some sources in the 1400s. OK it is volley fire.
    I had a 45lb laminated reflex bow and the best range I could get was about 240 yards. The yew long bow from some sources suggest 300 yards plus which I find worrying.
    Cheers Bob


    • Bob,

      I haven’t gotten that far yet, but, yes, airgun bullets will break major bones. I have an analogy about this that explains it pretty well. A .458 airgun bullet at 50 yards has the identical velocity, penetration power and energy as a 45/70 bullet at 300-400 yards. And we know from government testing done in the 1870s that the 45/70 retains superior penetration all the way out to 500 yards.

      B.B.


      • BB
        When you were at the FTW show and got to checkout the new crosman bull pup in the 357 caliber did they say if there would be any new pellets/bullets being developed for the new gun or are they just only offering the same ones already being used.

        Buldawg


        • Buldawg,

          I spoke to Crosman weeks ago about that, and they did indicate that they are looking to provide bullets for the gun. I know they are no longer selling the Nosler spitzers, so I have to assume that means they are looking for some new kind of bullet.

          B.B.


          • Bb
            Thanks I knew they only made one choice in the 357 caliber, so I was just curious if they were going to expand there offerings. but from what you say they are stopping one and may be looking at supplying another style. Its a good thing that PA has a pretty good selection. I think if you are going to market a new gun you should be able to provide ammo for it also.

            Buldawg


    • But remember that the arrows carry broadheads in front of them… them don’t work by tranferring energy to the targets, they work because they cut flesh with a razor sharp broadhead that will cause the blood loss you need to kill game. On armored knights, well, there is a lot of debate if the arrows of the time were actually capable of penetrating plate armor. They were capable of penetrating chain armor, however.
      Also, at the distances you mention, wind plays a big part! If you have actually shot your bows at those distances, with only 3 to 5 knots of crosswind you know you have a lot of compensation to hit the target.


      • Bob and Fred,

        In the Middle Ages Knights wore armor and rode horses that also were armored, but they made up a tiny percentage of the soldiers on the field of battle. (Even so, the well-armored King Harold was knocked off his horse by an arrow to the eye during the Battle of Hastings in 1066.)

        The vast majority of foot soldiers either wore no armor at all or had breast armor made of thick leather. Their helmets, if they had them, were likely leather as well.

        Michael


      • On armored knights, well, there is a lot of debate if the arrows of the time were actually capable of penetrating plate armor. They were capable of penetrating chain armor, however.

        The longbow did pretty well against armored knights at Crecy, Poiters, and Agincourt… But as you said there’s debate about the effectiveness of arrows against armor. Personally I would imagine that there are a lot of variables that come into play when it comes to penetrating plate armor: the type of arrowhead (Bobkin points vs. broadheads for example), the power of the bow, the range, where the arrow hits on the armor (plate armor isn’t of uniform thickness and there are weak spots that are lightly protected or not at all to allow for movement) the material the armor is made from (steel or wrought iron). There’s also the little matter of not needing to drive the arrow very deep to take someone out of a fight. After all if an arrow penetrates 2- to 3-inches or into someone’s shoulder they’re not going to be able to swing a sword/axe/mace very well. And then there is the question of whether archers of the time were shooting at the heavily armored knights or at their more lightly armored horses.

        Also worth remembering that military archery tended to be volley fire which meant you had a lot of arrows looking for those week spots. (Long bowmen tended to loose around 10 arrows a minute. If you have say 3,000 long bowmen firing volleys at that rate, that works out to 30,000 arrows a minute. While a charge only lasts a couple minutes…


        • Bobkin or bodkin? In his soliloquy Hamlet contemplates stabbing himself to death with his drawn dagger, that “he himself might his quietus make / With a bare bodkin.”

          Does bodkin refer to archery tips as well as those of blades?

          Michael



          • This is my third attempt to post this… If it doesn’t go this time, I give up.

            The term Bodkin comes from an Old English word which refers to a type of dagger. However a bodkin point is an arrow head with a square/diamond profile that is designed to punch through armor.


            • J,

              When you see that a comment didn’t make it, there’s a 99.99% chance that it was caught by the spam filter. Reposting your comments won’t change that. So, posting it just once is all you need to do. We’ll find it & approve it.

              Edith


              • Hi Edith just wondering how BB is doing with his pancresnticis. I have had it since 2000 had surgery for cist in 2002 and wipple in 05. VA put me on slow release morphine [ 30 mil ] twice a day and megastrol asitate to help appetite. take lots on laxatives to keep things going. lol all nagging pain is gone. still have small attacks but only last a couple of minutes at most. feel like im 20 again. hope this helps in some way. God bless tom


                • Tom,

                  B.B. hasn’t had pancreatitis in years. It was just that initial time in 2010, and then it was fixed by a fabulous doctor (after several hospitals & doctors really messed things up).

                  I remember that time like it was yesterday, and I’m so sorry to hear that you are repeatedly enduring these episodes.

                  Edith


          • Classical bodkin points were pyramidal in shape; the point initiated the puncture and the four edges then acted cut the plate and curl it inwards. The point would only be a bit larger in diameter than the shaft, opening the plate enough to let the shaft penetrate.

            The closest modernly available point would be a “field point” (not to be confused with the stamped tin “target point”) — although the transition from the narrow part of the point to the shaft diameter would retard penetration.




  2. This is going to be a great discussion! Most airgunners, most especially the newbies transitioning from powder burners, fail to grasp that velocity is not something we should give much consideration to. The only reason we should consider that number is in relation to how much mass to we want to hurl downrange and how far do we want to hurl it with accuracy, or should I say precision?

    As you pointed out, when we start thinking about big bore air rifles, we need to step way back in time with our thinking. Although it is possible to build an air rifle that will hurl a .458 monster slug through the air at 1400 FPS, it probably would not be practical to do such. You would have to dump a lot of air at very high pressure in behind that slug to achieve such. Fortunately, with that much mass we do not need to be going that fast.

    As far as the .257 Haley, there is an on going long range competition called the Pepsi Challenge. The objective is to see how far away you can bust open a can of Pepsi with an air rifle. The record so far is held by a .257 Haley Scandalous, probably the very rifle you were talking about. I watched a video of it ripping open a Pepsi at 614 yards. A 100+ grain slug might just do the trick at 300 yards.


  3. B.B.,
    Interesting topic. What differences are there in .303, .308 and .357 caliber air rifles that make some work best with diabolo style pellets and others work best with cast bullets?
    Thanks


    • It really has nothing to do with the caliber. It is more of a matter of how fast is the projectile moving, rifling twist rate, the length of the barrel, etc. The diabolo is designed for subsonic flight.


    • Tabrown,

      Actually I have never found that spitzer (pointed) bullets work in big bores, with the exception of the Nosler Ballistic Tip 145-gran bullet that was made for the Rogue. However, Haley’s .257 not only worked with a spitzer, it worked with a jacketed slug at 1100 f.p.s., so what do I know?

      B.B.




  4. Oh, boy, you’ve opened a big one this time.
    My prediction is this one will go on (or shall we say “continue from before”) for years. “Before” in this context being at least 2000 years of recorded history, anecdotal and verbally handed down, probably at least more like 10,000 years.
    Your capsule rendition of how all this projectile stuff works is excellent.
    And darn that column format constriction. About the only way to streamline the subject any further would simply be to say, “It’s complicated.”
    This is going to be fun.


  5. Having messed with cast bullets and lead RB most of my life, I know air rifles could duplicate the ballistics of firearms cartridges of the past like the .25-20, 32-20 and ..44-40 with readily available cast bullets. The problem is that most shooters know little about those obsolete cartridges, or the men who used them. Hope your series changes that and maybe makes some large domestic manufacturer of air rifles build some for us that we can affford and are readily available.


    • For affordable big bore airguns that are readily available it’s tough to beat the korean guns or even an airforce gun. The dragon claw and recluse have gotten rave reviews. A sleeve for the barrel on the recluse has resulted in amazing accuracy. Shame that B.B. was never able to finish his review of the recluse.

      kevin


      • Kevin,

        You are right — the Korean big bores are bargains, as long as the buyers know they are getting 200 foot-pounds and not 500. They have been used successfully on whitetail deer, but the range has to be close.

        And the Korean rifles in .45 caliber have bore sized 0.451 instead of 0.458, so they can use the much lighter pistol bullets. That way, they keep their muzzle velocity up.

        As far as accuracy goes, I have tested at least 10 Korean big bore so far and not one has been able to put 10 shots into one inch. But a couple were able to keep 5 in 1.5 inches, which is decent.

        B.B.


      • i disagree that they are that affordable bargins, or even popular . If they could get the price down to where it is equal to a BP inline , then the idea of big bore airguns could take off with the average deer hunter.. It would maybe popularize them with game depts ,as here (speaking from an eastern hunting perspective) there are many areas which the short range would appeal to safety concerns in populated areas where deer problems manifest themselves. The problem is ,except for the few on this blog , there is a vast ignorance in regards to the terminal ballistics of all airguns, or most guns for that manner…. .



          • Kevin, Well you are right, you wouldn’t have to buy powder or caps for them (if you can ) , but you still need fill equipment for PCP’s. Heck, you cannot even get the fudds to buy good quality RF ammo, cleaning supplies., targets, or even vote…it makes my head hurt…. I usually save my thoughts like this for Wednesday which normally is reserved for my hate meditation ,and iI don’t like to start early.


            • Robert,

              You’re right of course. You do need fill equipment for your pcp’s. You only have to buy it once FOR ALL OF YOUR PCP’S if it’s the right equipment.

              I think big bore airguns make more and more sense especially during these times of ammo shortage and price escalations. The price of an inline or centerfire seems irrelevant when you can’t find or afford ammo.

              kevin


              • If it were legal to hunt game animals with them, it would be a major priority for me.And I have considered relocating due to the length of time it would take for even Texas to recognize the effectiveness of airguns on game.We can’t even legally take dove( with the exception of Eurasian collared dove) with less than a shotgun.


                • Reb
                  Move to the Heart of Dixie, we just passed into law the hunting of deer with an airgun of .30 caliber or larger. And BP ammo is still plentiful and reasonably priced.
                  Long live Dixie

                  Buldawg


              • All true, but there is one major problem which has kept me from committing to the WWoPCP (Wonderful World of Pre Charged Air.)
                Once that hand-pump/scuba connection goes down, you’re out of business. Even if you popped for the (horrifyingly) expensive high pressure electric pump…well, the power has been known to fail…
                Perhaps to put too fine a point on it, figure you actually only have to buy it a minimum of twice. One for your primary and the other for your back-up.




          • That’s a good point. As long as we, airgun hunters, don’t go into some “controversy”, the likes of “crossbows X compounds” or “in-line X sidelock muzzleloaders”. If we keep ourselves accepting all airgunners just as airgunners, and not selecting the ones who prefer the same kind of equipment as we do, I am fine with an “airgun only season”.
            Now, since we are in the subject of big bore airgun hunting… I really can’t believe when I see my friends going after wild boar with one of the 9mm air rifles… they seem to shoot a .355 90grain “bullet” at speeds that put them into .380ACP class, and I would never ever hunt anything with a .380… how can that be a good recipe for wild boars? Is there some magic that make such a little bullet perform differently when shot from an air rifle?



            • Fred_BR
              To all here on this forum, I have hunted wild boar in the green swamp area of Florida around cross city and perry FL. I can tell, you that a 9mm, 357 or even a .50 caliber air gun is not going to cut it when you are hunting 600 LBs plus monster boars that if pissed off from a shot from an air gun will turn and hunt you with a unforgiving relentlessness that you would not believe if you have not seen it in person. I have personally hunted and shot at 600 LB boars with anything from a 30-30 and up to a 44 magnum back in late seventies and seen a 44 mag ricochet off the skull of a boar and in turn be chased by that boar up a tree. At the time I was 19-20 years old and we found an old man ( 45 years old ) that had grown up there and hunt those boars all his life and he did not carry a gun, he would hunt them with 8 to 10 pit bulls and 2 Airedales because the pits do not bark so the Airedales would howl to let you know where the pits were running the hog. when the pits had the boar tired out and were holding it down on the ground he would run up and kneel across the boars shoulder and jaw and stick a 10 inch bowie knife in their throat and stir like a pot of chili. The hog now matter how big will suffocate on it own blood in five minutes and would not get the chance to turn and hunt you down. Myself was never that brave to not have a gun on me when hunting them but his method of catching and killing them was most definitely the safest and most humane. There is a difference between a wild pig and a wild boar that can get as big as a cow with 8 to 10 inch razor sharp tusks and is not afraid of a human at all.

              Buldawg


          • BB: Yes , I think they would, but here they would tack it onto the muzzle loading season which runs after the regular gun season (although you CAN use BP guns in the regular firearms season) , and that would make them compete with the BP guns and crossbows, which many have already. Another problem here is that our tyrant of a governor has appointed two seperate committee’s, one ,which is exploring limiting powerful airguns by possibly eliminating mail order /internet sales of them , and two , the sale of lead pellets and bullets for hunting. We already cannot buy any kind of ammo through the internet or by mail now. But you are right in that some hunters may become interested enough through blogs like this to become proactive in fighting such legistlation if it affected a popular sporting use they enjoyed.


  6. B.B.,
    Very timely and interesting topic. I am particularly interested in hollow points (Big Bore & Small Bore). How they stack up against round nose/ flat nose bullets and pellets.
    Would a hollow point Big Bore bullet, that deforms in a way that it does not pass through the animal, produce hydrostatic shock??. If it did not exit the animal would it not transfer all its energy to the animal??


    • Peter,

      A hollowpoint doesn’t create hydrostatic shock by itself (only velocity can do that), but the deformation does both enlarge the wound channel and also transfer more of the bullet’s energy to the game. So hollowpoints are useful in big bore airguns.


    • Location, location,I generally prefer a neck shot.You can tell by the instant reaction that the game has suffered terminal shock. Not only does this offer more resistance to over-penetration but also severs the connection from the brain to the rest of the body. And it’s easy to know where the spine is, just below the cranium. My deer hunting buddy has discovered this and incorporates it for it’s tendency not to damage the edibles and not having to track the animal. Of course he still uses a 30.06.

      Reb



      • I have put down a couple deer which were shot in the neck and suffered terrible wounds. Often the trachea is blown away, or with that popular idea of the inexperienced, the head shot, the lower jaw is destroyed. Often the deer drops instantly ,but then revives itself and gets up and runs away to die horribly.


        • I have only shot two deer in my life behind the shoulders. Both of those were when I was a teenager. Never again. I hope I never become so callus that I am not greatly disturbed by such.


      • My preference of shot placement has always been and will always be the brain. Many deer hunters do not like to do such as it damages the rack, however I discovered many years ago that it is not edible. Also, it is not necessary to track one very far. This is also quite effective with smaller and larger game.


        • On the small game, squirrel and rabbit, I prefer to heart and lung, but headshots when the range is really close, the reason being you have about twice as large a target and with a powerful air rifle it’s a definite kill. The heads are so small and brain even smaller and glance shots are not allowed in my book, with the breadbox you have all the arteries of the heart, chest, neck, heart itself, lungs, and getting into any of it they don’t go anywhere. If your gun can’t punch the shoulder bone it isn’t made for hunting.


        • RR: I have shot many deer , usually two to three every year , (or many as I’m legally able to), so I speak from some experience . I have also butchered many steers,pigs , and chickens ,as well as stuff I’ve trapped. Killing anything involves some cruelty. This is un-avoidable, and is repugnant to most of folks today which use surrogates to accomplish this unpleasant task. I will agree to dis -agree based on my own experiences. A shot through the chest with a bullet or arrow that leaves an entrance and exit hole will result in a humane and quick death with little meat loss. Tracking the game a short distance to follow up is part of woodsmanship and a skill required if one is to hunt ,as is the act of killing. And yes, I have lost one or two , I’m far from perfect,and it has stuck with me….


          • I know exactly what you mean, while out squirreling with the new gun I shot two dead that went straight to the ground and DOA, but the baby squirrel that fell from a tree on the otherside of the property (they were different gangs, I didn’t kill its mother or anything) came home and we nursed it back to health for two days, coolest animal ever would make an awesome, loving, interesting pet, but anyway, the morning of day three we woke up and it was dead, just sleeping peacefully and unbearably adorable. I cried. A grown man. I fell in love with it and could tell what kind of relationship could’ve been had. Point being, I shot two dead but cried for a third. We love animals and always give them the respect of a painless, quick death, and our hunting w.o.c. needs to be up to the task of providing a clean kill. Wherever we choose for shot placement, if your gun is teetering on the weak side of being capable, your not respecting your quarry.


      • Reb, read below, I think we’re on the same page, they can’t run if they can’t breathe, to put it bluntly. Also, trying my best to get the pellets out, should be on the road tomorrow.


  7. B.B.,
    I remembered in your previous article, that it is very difficult to load a big bore bullet into an airgun as compare to a .22 airgun pellet. Does the Quackenbush big bore airguns have the same loading problem? If not, how did Quackenbush get solved it?


    • Joe,

      All guns- regardless of who designs them — solve the bullet loading problem with the leade — a tapered entrance into the rifling at the breech. Dennis’ rifles will accept some large bullets, like the 405 shown here, but not others. The 510-grain bullet has a nose that is too large and long to be loaded into a Quackenbush rifle without alteration to the leade.

      B.B.



  8. B.B.,

    The discussion about big bore guns and projectiles is interesting. I especially enjoy reading about antique big bore guns. Wouldn’t it be fun to shoot a Uberti replica of a Girandoni rifle!

    A box of soft, 330 grain .458″ bullets is sitting on my kitchen counter in anticipation of a soon-to-be-delivered Quackenbush rifle. It will be an interesting experiment.

    Other than brief mention by Lewis & Clarke, are there historical accounts of antique big bore air guns?

    RB


  9. I have a related question which is not necessarily airgun specific– how did everyone decide on the bore sizes? For example almost all airguns come in .177, .20, .22,. 25 and then the exotic larger calibers. Is there a reason why those specific numbers or is it more of a standardization? Why aren’t there, for example, .15 bore airguns– let’s say for 10m matches.

    When I received my basic cadet training in India we trained on .303 WW2 rifles. But that wasn’t the same as the service rifle bore which was 7.62 then. How did everyone arrive at these specific sizes?

    Thanks,
    Roy



    • Actually, Roy, .303 is a measurement of the projectile diameter (more or less) in fractions of an inch. 7.62 is more or less measurement of projectile diameter in metric standard. Guess what? They’re both the same diameter, more or less.
      But that would be too simple, wouldn’t it? If one were to utilize the full nomenclature, such as “7.62 NATO” or “.30 Carbine” or “.30-06” or “.32 ACP” or possibly “.303 British” or even “.303 Savage” not to mention “7.62x 54mm Russian” you would be describing a number of extremely different, non-interchangeable entire cartridges…all of which launch projectiles at different velocities but of, guess what?
      The same diameter, more or less.
      Nothing is simple, is it?


      • 103David
        Yep got me a model 99 savage rotary breech lever action chambered in .303 savage, it is a accurate gun to 100 yards you just don’t want to carry it very far as it is no light weight.

        buldawg


      • That’s what confused me– .303 in mm is so close to 7.62 and yet the Brits bothered to change their standard ammo by a tiny fraction to the 7.62. There must be some science behind the minuscule difference in calibres.

        I am looking forward to BBs article on how the modern calibres came about.

        Roy


        • There must be some science behind the minuscule difference in calibres.

          Not really. Or rather not as much as you’d think.

          That’s what confused me– .303 in mm is so close to 7.62 and yet the Brits bothered to change their standard ammo by a tiny fraction to the 7.62.

          This is the short version of what happened and why. If you want the long version, check the links I’m including. They should give you more information and additional places to start researching stuff.

          Anyway… The .303 British cartridge (AKA 7.7x56mmR) is a rimmed cartridge developed in the late 1880s for use in the Lee-Metford and later Lee Enfield series of rifles. These rifles were used into the 1950s (and later as a reserve weapon) by Commonwealth forces. The .303 cartridge was also used in Commonwealth machine guns until about the same time. It was refined repeatedly over that time and served well through 2 world wars and numerous other conflicts. However by the 1950s it needed to be replaced by something more modern in order to work with newer weapon systems and a newer environment.

          The British switched the the 7.62x51mm NATO round in the 1950s for a number of reasons. The first was the need to use a standardized cartridge to simplify their logistics. As part of NATO, British forces needed to be able to use the same cartridge as their allies. That way if British troops had to help fight a Soviet invasion of Western Europe, they didn’t have to worry about finding .303 British ammunition. They could use the same stuff the French, Germans, Dutch, etc… were using. (This is the same reason that the US replaced the .30-06…) Then there was the fact that the guns chambering .303 British were getting a bit long in the tooth. The SMLE was a good gun in its day. But when semi-automatic rifles like the FN FAL, M14, and HK G3 (not to mention AK47) came along the SMLE needed to be replaced with something more modern. In this case that was the FN FAL (and later the L85 in 5.56x45mm). And at that point the British adopted the standardized NATO cartridge. They weren’t happy about it since it wasn’t the cartridge they would have preferred, but they did it because of the advantages a standardized cartridge in a modern rifle offered.

          You previously mentioned that you used WWII Enfield rifles chambering .303 in India. The reason India used two different calibers had to do with what they had on hand. India is/was a commonwealth nation. And it had manufactured a lot of Enfield rifles over the years. For a while they were happy with the SMLE. But after (losing) a couple border skirmishes with the Chinese, India decided to upgrade in the ’60s. And when they did they went to rifles chambering the 7.62 NATO round (in this instance the FN FAL) to make buying guns and ammunition easier. Because reequipping an army with an entirely new rifle takes time, India also produced a version of the Enfield (the Ishapore 2A/2A1) that chambered the 7.62 NATO as a stopgap until they could get enough FN FALs. When that happened the Ishapore 2A/2A1 was withdrawn to the reserves and the older SMLEs were probably relegated to cadet training. Things are probably a bit more complex than that, but those are the basics.

          (1. https://en.wikipedia.org/wiki/.303_British
          (2. https://en.wikipedia.org/wiki/7.62%C3%9751mm_NATO


  10. Does anyone know what it’s called when you have a weathered stain and then the fluorescent green in the closed grain? I can’t find info on the process anywhere, I have the stock shaped, sanded, two layers of reddish mahogany sanded out to a brown weathered look that I want to offset with a fluorescent color, the grain is gorgeous, I really lucked out with this stock, it’s beautiful, coming out amazing. If I can’t get a color in Im going to walnut over the red.






        • RD,
          Just, for your amusement, in the late 60’s I found myself working for a (VERY) major and somewhat famous guitar manufacturer in Kalamazoo, MI. The Sunburst was done with an air-brush/air-gun like device. (See, I always try and get a air- gun reference in there somewhere.) None of which ever done by me.
          But what I did do was occasionally “Un-Finish” guitars for the repair Department. This was removing the finish, to sometimes include the “Sunburst.” Done properly, this involved brushing on an undoubtedly hideous, carcinogenic, probably plutonium based, and certainly subsequently banned by the EPA (plus the Hague convention of 1907) gel of some sort, standing back and counting to 100 or so, and then peeling the Sunburst off in a single gelatinous piece.
          Being, in essence, the artist that I am, I’d hold it up to the low October sunlight coming through the hard-core industrial windows and admire the beauty of it all.
          Cool.


  11. I posted a question, at the end here, regarding valve design and how the exhaust valve can withstand the large volume of air passing by without the seal rolling. After submitting it I got a screen telling me “Page not found”. I had to close the window and reopen to check if it had taken.
    B.B.,
    I would be interested in seeing how these guns that move so much air, seal their exhaust valves.


  12. The things you are talking about with the big bores can be scaled down to the small bores also.

    When I shoot a squirrel at 50 yards with my .177 Hatsan QE and the .177 Marauder with a 10.5grn. pellet at 1010fps. And its a heart lung shot the pellet is such a small diameter the pellet will just pass through. The squirrel will just sit there and all of a sudden fall over. The smaller faster flying pellet is like a needle piercing through.

    Now if I take my .25 cal. Marauder that’s shooting a 31grn. pellet at 900fps. when it hits that same squirrel at 50 yrds. with the heart lung shot the squirrel gets knocked right of the branch. And most of the time there is a entrance hole but not a exit hole And I find the pellet inside took a different path.

    So which way is better? I think it depends on where you are shooting at. If I’m shooting out were I don’t have to worry about where the pellet goes the .177 cal. would work. If I’m wanting to keep the pellet from ending up in the wrong place then maybe the .25 cal. would be better.

    I myself like the .25 even though there is not hydrostatic shock of course but when the squirrel gets hit and knocked of its feet that still has to make the animals heart rate, nerves and other things accelerate, I guess the adrenaline would even kick in. That would probably make the blood pump out faster.

    To many scenarios to say what would be best though. Piercing through or a thumping hit. And then start talking about wind and distance with accuracy. Its all the same whether its a small bore or a big bore. Its just on a different scale.


  13. Tom,

    I am a bit confused, perhaps because I am not a hunter and shoot airguns only at targets, spinners, and plinking-type items such as aluminum and steel cans.

    If given their sub-1500 fps. velocities, no airgun can ever produce hydrostatic shock in game, why do airgun manufacturers, retailers, reviewers, and hobbyists bother to calculate foot-pounds or joules of energy? It is a pointless statistic, utterly irrelevant, no?

    Penetration depth in ballistic gel and average wound diameter in ballistic gel would be useful information, as is velocity for a given diameter and weight pellet or bullet, but foot-pounds/joules are meaningless with airguns, right?

    Michael


    • Michael,

      What an astute observation! I guess it is because it took us about 30 years to get them to include foot-pounds of energy with their velocity figures. They need something they can hang their hats on, to appeal to the masses. Something that is understandable. Something concrete.

      Today’s topic isn’t easy to comprehend — especially if you have never hunted game and seen these results in the field. We are having a doctoral-level discussion today, and airgun marketeers are still pushing their gun sales with kindergarten data.

      B.B.


      • Tom,

        It seems to me that for certain VERY specific applications, having an airgun (or powder burner) that has low velocity, NO penetration, but foot pounds equal to a heavyweight boxer’s overhand right, just might be useful. I’m thinking of bean bag guns used to knock someone off his feet but not do more than badly bruise him. I used to know a police officer/law enforcement instructor who once watched his partner shoot a belligerent drunk in the gut with a bean bag. It knocked him down, knocked the wind out of him, and sent him to the ER with a very sore tummy but, according to the story, at least, no internal injuries, just bruised abdominal muscles.

        Michael


        • Hmmm.

          I just reminded my wife of that story, and she remembers it very differently. Different enough that I now can’t be certain if it happened that way or was a story about a training exercise he took part in in which the belligerent drunk was a fellow officer under a lot of padding or even something else entirely.

          I have no idea where he retired to, so I doubt I’ll ever find out for certain. Too many memories, too few brain cells!

          Michael


      • Tom,

        I occasionally watch Mr. Hollowpoint/Robert Vogel’s super slow-mo videos and still “after” photographs of his big bore bullets making their way through slabs of ballistics gel. They are, I think, quite instructive.

        The proof is in the pudd . . ., er, gel, I guess.

        Michael


    • If given their sub-1500 fps. velocities, no airgun can ever produce hydrostatic shock in game, why do airgun manufacturers, retailers, reviewers, and hobbyists bother to calculate foot-pounds or joules of energy? It is a pointless statistic, utterly irrelevant, no?

      Penetration depth in ballistic gel and average wound diameter in ballistic gel would be useful information, as is velocity for a given diameter and weight pellet or bullet, but foot-pounds/joules are meaningless with airguns, right?

      Kintetic energy figures are not entirely useless. You still need to meet a certain minimum impact energy level in order to ensure adequate penetration so that you’re able to deliver a wound that will be fatal. Kinetic energy levels can give you a rough idea if a gun will be suitable for a given use, even if it may not be a perfect descriptor of the terminal performance you’ll get with pellets. Where it comes in handy is when you’re trying to explain to what I’m going to refer to as “a dumb kid” why he shouldn’t use a very low powered BB gun to hunt x, y, or z animal. You can either write a book which he won’t read, or just tell him his Red Ryder doesn’t have enough power and that he needs something that produces at least x ft-lbs of muzzle energy (and that x ft-lbs of muzzle energy should probably have a substantial safety margin factored in).

      This is rather an extreme example, but it should illustrate the point. Suppose two kids go squirrel hunting with different airguns in (nominally) the same caliber… One kid uses a Daisy 105 Buck. One kid uses a Benjamin Discovery (in 4.5mm). The Daisy Buck produces a KE of less than 1ft-lb. The Benjamin Discovery produces somewhere in the ballpark of 18-19 ft-lbs. There’s a huge difference in the terminal performance of the two guns that you could describe in detail. But what it comes down to in the end is the kid with the Daisy Buck is only going to injure squirrels, regardless of where he shoots them, because his gun doesn’t have enough power to drive a BB through the squirrel’s vital organs. The kid with the Discovery is going to kill squirrels, assuming he puts the pellet in the right place, because his gun has more than enough power to drive a pellet clean through the squirrel.


  14. I keep getting booted off the comment section when I try to share. Twice I have tried to share videos of wood staining techniques for RifleDNA’s project and still don’t see one.


  15. I have no doubt about the accuracy of the observations about large slow bullets from air and blackpowder versus smaller faster moving bullets from smaller firearms. But I also suspect that what goes on is so complicated that it becomes hard to generalize about black and white differences between the two. Big bullets create a wound channel, but with the deformation from the cast lead that was a heck of a channel. And don’t deforming bullets transfer energy more than their size indicates? That is tied up with the definition of an inelastic collision. Moreover, surely something causing this must trauma will cause some kind of shock wave through the body. Is there a distinction between what makes a shock wave and what does not? I picture more of a gradual scale. I once read a detailed study of the damage caused by a bullet wound and it was very complex. There was disintegration caused by the projectile. Then there were two types of cavitation/tearing, permanent and non-permanent. The wound channel proper was made up of some blend of distintegration and permanent cavitation. Outside of the non-permanent stretching and tearing were some kind of reverberations. I am skeptical that all of this jumps into existence above a threshold velocity.

    The small modern bullet also has its limitation. There are plenty of reports of the modern M4 ammo zipping right through targets with little effect, so that the wounded don’t even know they are shot. That caliber has plenty of velocity. Either it is going so fast, it doesn’t have time to transfer energy or something about bullet design prevents expansion and the targets are just getting poked with a tiny puncture. The military ammo with the green tips seems to be the culprit. Anyway, it seems like bullets have been doing serious damage long before modern firearms. And we can’t even say that range was a restriction since Civil War sniping ranged out to 800 yards and in some cases out to a mile.

    Charles, thanks for the reference to the combined Gas Law. I got mixed up between Charles’s Law, Boyle’s Law, Raoult’s Law, the Zanthoff factor… There is a lot of terminology to keep straight in chemistry.

    Edith, good observation. I was referring to the bullpup design, not to a specific Bulldog model which I had not heard of.

    Matt61


    • Matt,

      When I was proofing today’s blog last night, I stopped cold & told Tom I didn’t understand what he was saying. In fact, I thought he’d mistyped the text. After explaining things to me, I was a like a deer in the headlights. More explanations didn’t help. He added more text to the blog. He re-explained things to me. I sat there open-mouthed and totally baffled. I finally said that it’s okay if I don’t understand it, as I’m probably the only one.

      More discussion followed — and then a lightbulb went on in my head! I need to compare these things to something I could easily understand. And so. . .

      A big firearm projectile can be likened to a person walking slowly toward me and bumping into me. I might be rocked. I might stumble, but I probably wouldn’t be injured.

      A smaller firearm projectile going much faster can be likened to a prize fighter standing next to me, and hauling off and punching me in the head with all his might. That would cause serious injury and possibly kill me.

      A much smaller airgun projectile going very fast is likened to someone standing next to me and quickly jabbing me in the side with their index finger. I might cringe or say “Ow!” but I’m not going be hurt, die or even stumble.

      And that’s how I managed to understand the comparisons in today’s blog.

      Edith


      • A big firearm projectile can be likened to a person walking slowly toward me and bumping into me. I might be rocked. I might stumble, but I probably wouldn’t be injured.

        A smaller firearm projectile going much faster can be likened to a prize fighter standing next to me, and hauling off and punching me in the head with all his might. That would cause serious injury and possibly kill me.

        Edith I’m not sure that’s a good comparison since a large slow bullet kills just as dead as a small fast one. They just do it in different ways. This might be a better comparison. A large, low-velocity firearm projectile could be compared to a wreck where a car gets hit by a loaded semi doing 30-40MPH. A small, high-velocity firearms projectile could be compared to a wreck where a car gets hit by a Dodge Charger doing 200-250mph. In both cases the person who gets hit probably isn’t going to have a good day. The question is just how messy the results will be.


    • Matt,

      I vaguely recall reading, a very, very long time ago, that after extensive studies the Pentagon concluded that a seriously injured enemy soldier is of much more harm to the enemy army than is an instantly killed enemy soldier. While our military has a strong “no one (even deceased) left behind” ethic, that is not the case with all armies.

      Leaving a dead comrade’s body behind for later retrieval is one thing, but carrying a wounded comrade and then providing him or her with life-saving treatment is, on a large-scale, a logistical nightmare for a fighting force.

      Therefore, the story went, the emphasis changed from one of big, heavy, powerful, long range rifles to, for better or worse, the M-16.

      Michael


    • There are plenty of reports of the modern M4 ammo zipping right through targets with little effect, so that the wounded don’t even know they are shot. That caliber has plenty of velocity. Either it is going so fast, it doesn’t have time to transfer energy or something about bullet design prevents expansion and the targets are just getting poked with a tiny puncture. The military ammo with the green tips seems to be the culprit.

      Welcome to the wonderful world of full-metal jacket ammunition. Per the Hague Convention of 1899, the armed forces of the countries that signed the Hague Convention are prohibited from using ammunition which expands inside a person’s body (like say hollow-point or soft-point hunting ammunition) against people. The European nations who crafted that treaty felt it was unnecessarily cruel. So starting around 1900 ammunition was completely encased in a hard copper jacket to keep it from expanding.

      In your specific example modern, relatively long 5.56x45mm NATO rounds used today tend to poke small holes through a person due to the small diameter of the projectile. Well that and the fact that the current twist rates stabilize the bullets better than the combination (twist rate and bullet weight/length) that was used during the Vietnam war. (The lighter bullets used back then tended to tumble when they hit a person producing very nasty wounds. Sort of like the wounds produced by the .303 British Mk 7 bullets, though the reasons were a bit different.



  16. B.B., awesome topic, I am always interested in ballistics and often try to retrieve my pellets to check rifling, mushroom effect, or barely any change at all in some pellets. It has helped me choose what rifles to shoot with what pellet whether hunting or target shooting for a given effect. Also helps with my shooting distances for a particular pellet if it keyholes at longer ranges. If I shoot RWS hollow points at 80 to 100 yards in my .25 cal Marauder they will keyhole the target sometimes so I keep them at 50 yards or so when hunting. Love ballistics…



  17. Tom,

    I do not believe I have requested a report on a specific airgun before, but I just can’t stop looking at the Black Ops Junior Sniper Air Rifle on Pyramyd Air’s website. Yep, it must be 100 percent plastic, but it’s less than $60! The cheekpiece and LOP probably would require that the buttstock be cut off and replaced with something ergonomic and adult-sized, but the claimed accuracy is tantalizing, and it looks like it has a pumping lever similar to the easy-pumping Daisy 880. A 6.2 lb. trigger is not unreasonable if everything else is good.

    Remove the sights and put a red dot on that generous rail, epoxy a homemade moderator on the barrel shroud — my imagination runs wild when I think of that as a modification platform.

    Michael


  18. Here’s a question.
    If we have a gun be it a big bore or small bore air gun that is shooting a certain pellet that is the most accurate. And its velocity is consistent from that gun.

    How would you know what range that combination would be good at? At what distance would the pellet stop piercing all the way through the animal and start penetrating and stopping in the animal.

    When the pellet stops piercing all the way through wouldn’t that be your effective range for that animal with that combination?



      • Guynfun
        Got my whisper listed on GB today and the payment for the nitro venom will be there Thursday, so I should have the venom next week. Checked prices on crosman for piston seals and a nitro piston for the Firepower and the Venom for if it may need a seal, they were not that bad as the seals are 1.15 a piece and the nitro piston is only 26 bucks plus the 4 bucks shipping. so for under 35 bucks I can make the Firepower a nitro gun and have seals for when they tear them up. They both take the same parts through out the guns, can’t get any better than that.

        Today was a doctor visit day and he was not even there, he has a policy if you miss an appointment it is a 40 buck charge before he will see you again, I wonder if I can charge him 40 for not being there when I was HA HA. This is not the first time its happened and not even a call to let us know. So now I got to get to the doc this week and put my plans for machining the tubes and barrel on hold as well as the sighting in of the guns till I can get an appointment to see him. it may be just as good because I will have my nitro next week also, so will be doing a whole day of sighting.

        Buldawg


        • buldawg
          That’s cool about the nitro piston fitting your other gun. You will have to let me know more about that if you ever do it.

          And me and the youngest daughter have a eye doctor appointment Saturday. We been waiting for 2 weeks. That would be a bummer if he doesn’t show.


          • Gunfun
            If my whisper sell for what I have it listed at 150.00 auction or buy it now at 160.00 I was going to use that money to get the seals and piston. I don’t know if I will put the nitro piston in the Firepower yet or not. I will see how the venom shoots and may just wait till the Firepower starts to degrade because it is very smooth with no real spring noise or much recoil. That is why I was so disappointed with the whisper because the Firepower is just that much better.

            Yea I hope your doctor is better than mine for being at the office regularly, Mine has just changed offices and is still not up speed, but he is the one supporting me in my disability claim and also the one that got the right test done to save my life with the heart caths so I will stay loyal as ne is very good just not always dependable.

            But I will get to see him and then get back to finishing my projects and sighting in sessions.

            Buldawg


            • buldawg
              You have been trying to sight them in for a while now. You got to get it done.

              I got all mine on the money finally. Now I just got to make sure they don’t get knocked around. Got em locked up safe and sound.


              • Gunfun
                Yea I do, it just seems when I plan to do it something comes up that I have to change my plans or I am not feeling good. It is going to get done by the end of next week come hell or high water.

                How are you feeling, have you got over your cold yet or are you still fighting it. Hope you are doing better.

                I know I have got to set a date to sight the guns in and stick to no matter what, I think I am going to wait till I get my nitro gun so I can do them all at ounce and next week we are supposed to be getting a cold front so it won’t be as hot hopefully.

                Buldawg


                • buldawg
                  Got a bit of a cough left and some chest congestion. Finally starting to get my voice back. I was hoarse for 2 days. See you couldn’t even tell I couldn’t talk when I was typing my replies. 🙂

                  Yep the cold front is suppose to be pushing in tomorrow after the rain. Its suppose to be in the high 60’s for Thursday, Friday and Saturday. And sun shinny at that. Should be a nice weekend.


                  • Gunfun
                    Yea we will get that same cold front only a few days later than you.

                    Glad you are getting to feel better and you are right I could not tell you were hoarse when we texting or posting.

                    buldawg


                    • buldawg
                      The cough and congestion wants to keep lingering on for some reason. I usually don’t have problems with colds. But this one has been a pain in the you know what. Everywhere you turn somebody has it right now in our area.

                      Any luck with the Whisper yet?


                    • Gunfun
                      The range finder reticle is the ones that have the lines below the horizontal crosshair that taper down in length as they drop down each mildot below the horizontal crosshair and they do not have any mildot above the horizontal crosshair. It has a plain black reticle or can be red or green. I do like my Hawke scope like you get and it is on my Hatsan and the half midots are definitely the way to go but I just cannot afford the 150 plus for the side focus Hawke scopes for every gun. I got the Leupold scope from ebay for 52 bucks including shipping so for the money it is good and it has the external windage and elevation adjustments that have the numbers on the outside and can be zeroed after sighting in and the illumination turret is canted off to the left of the top center so you can see the elevation turret numbers without looking around the illumination turret.

                      The Hawke may end up on the 177 2240 for the hunter class shooting, I just will have to wait and see if the range finder is as useable as the 1/2 mildot is. I do know what you mean and like the Hawkes the best just cannot afford them right now.

                      I will know more about the range finder reticle as I have not used one before either so it will be a learning curve for me as well. I wish I could have a Hawke on every gun but it is just not possible at this time, so I have to make some compromises.

                      Buldawg


                  • Gunfun
                    I had to reply here because there was no button below your reply. Have you seen on the news about this virus called Entrovirus 68 that is going around that is a respiratory virus that can be very serious and hard to treat, it has been on the news here in AL and is supposed to be widespread across the country. Check your local news stations website under health and look for Entrovirus 68. It is not to be taken lightly as it can be serious.

                    I got the whisper listed, but no watchers or bids yet, it is a 5 day listing so if it does not get any attention in the 5 days I will lower the price some so I can get it sold. If it does not sell for a little profit I will just send it back as I have 90 days to return it.

                    Got a doc appointment for 2 today so he’s back in the office, I ought to try and charge him the forty bucks for being a no show yesterday like he does to his patients that don’t show for their appointments. LOL.

                    Just could not get myself up and running this morning, it was one of those days where my body will not cooperate with my mind.

                    Buldawg


                    • buldawg
                      Yep that’s all you hear on the news here also.

                      And ask your doc if you can have today’s visit free. 🙂


                  • Gunfun
                    I am glad you are aware of that virus as I did not think you had it but just wanted to let you know about it.

                    Just got back from docs and he was not there because he did not want to be there, he has just moved as I said earlier and the other doc that owns the building that he is leasing the space from had locked him out because there was a urine sample cup left in one of the sinks and it pissed the owning doc off, so he changed the locks and my doc had to get a lawyer to get back in to treat patients. He has already found a new building to move to as he is not going to put up with that kind of childish behavior from the owner/doc he is leasing from, so it was not because he did not want to be there.

                    So I got that out of the way for another month so I can get back to my guns.
                    I will keep you informed,

                    Buldawg


                    • buldawg
                      Well good and bad about your doc. At least you know what’s going on.

                      And that means if you ain’t got them guns sighted in yet, you ain’t had no time to enjoy them yet.

                      I couldn’t go that long without getting them right.


                  • Gunfun
                    I do feel better about my doc and why he was not in his office and with him being my main backer for disability I am glad to know that he is moving to another office that him not being able to get in to provide care for his patients will not be an issue anymore is good.

                    You are right that I have not been able to enjoy my guns yet and it has been bothering me quite a bit. the whole ordeal with my hipacs stuff has really frustrated me and kind of thru me off my game so to speak. But I have got that out of my head and have my sights ( pun intended ) set on getting my tubes corrected and the 853 barrel done so I can get the 2240s together and be able to take all my guns to the range and spend a whole day getting them all sighted so I can enjoy them and be ready for the hunter target matches in November at the local club. I have a Leopold 3.5×10-40mm illuminated range finder reticle side focus scope to put on the 177 2240 for the hunter class so it should be a light accurate sweet gun for the hunter class.

                    Then by the end of next week I will have my nitro gun also and can get it all done in one day. My payment for the nitro gun will be there tomorrow and he should have on its way to me then also as I sent him cash so as not to delay shipping at all.

                    By Saturday the 20th they will all be done and being enjoyed as I have made that promise to myself.

                    Buldawg


                    • buldawg
                      That Lepould scope sounds interesting. I don’t like the illuminated stuff but it sounds like it has all the other right features.

                      Range finder reticle. Do you mean mil dot reticle? The best reticle I have found yet is the Hawke 1/2 mildot reticle. First it has the fine lines. And then the 1/2 dash marking lines. It makes pin point aiming a whole lot easier. Once you get more into yours you will see how it performs compared to others. And I’m willing to make a bet on that. At least you have one already. 🙂



        • Be sure to tell us about you NP conversion.I was wondering if that would have been a good idea on my QB-36 when you offered me your B-3 spring. I hope it goes well for you. Matter of fact,why don’t you guest blog it?


          • Reb
            Yea I did a lot of cross referencing with the crosman schematics to determine that my firepower is a Quest/Vantage/phantom/optimus clone and the same seal fits all those spring guns and the nitro venom/blaze so the nitro piston should fit in the spring guns also.

            I don’t know if it will fit the 36 but it very likely that it does and it is only 26 bucks with 4 bucks shipping, the crosman part # is BT9M22-00-5A nitro piston.

            If I do get the nitro piston and when I decide to install it I will do a guest blog on it. I have to sell my whisper first for the funds for the seals and piston.

            The Firepowers are for sale on airgun depot for 70 bucks refurbished, but are out of stock right now and for all I know mine may have been a refurbished one also.

            Buldawg



              • Reb
                That sound great and the nitro piston will make it smoother, Is that spring for the 36 only or do you think it would fit the crosmans and if so where did you find it at.

                Buldawg


                • I think the main difference was it’s compressed length. It’s still doing fine Except I’ve been soaking the seal for about 4 days now. I over-oiled it and overflowed the transfer port.
                  B.B.,
                  Is there any other position I should set it than on it’s butt pad? I don’t wanna break another spring.
                  Got the evaluation done this morning.They got fresh X-Rays of my back and I got that same old headshake from the radiology tech.
                  The need for further rehabilitation was discussed for a short while and they sent me home to wait for a call from SSA.


                  • Reb
                    I hope you get a good call from the SSA that is telling you that you are approved, I am still waiting for my hearing myself and it gets frustrating not knowing when or how it is going to go. If I don’t get mine I will have to start selling my toys I worked all my life to buy and enjoy just to survive, but we got to do whatever it takes to survive.

                    I think that if you over oiled the 36 and it is running out the transfer port that I would either position it so that the oil can drip out of the port or stand it barrel down so the oil will run out the barrel onto some rags or towels until you see it has stopped dripping. You sure don’t want to shoot it if it will detonate or hydraulic lock on the oil as that most likely break the spring, it can bend rods and break pistons in an engine so it could easily break the spring.

                    My B3-2 with the leather seal that I soaked just the seal in 30 wt motor oil for a week still smokes every time I shoot it and it has had at least 300 rounds thru it so the leather will hold the oil for quite awhile and should not need oiled for at least 1000 shots or more. I am going to go by when it quits smoking while shooting that is when it will get some oil put in the chamber port.

                    Where did you find that gas piston at for 18 bucks.

                    buldawg



                    • BB
                      I understand that resting the rifle on the barrel end is not a good thing to do but in the case of Rebs gun that has a air chamber that may be full of liquid oil. how would you suggest that he drain the oil from the chamber other than barrel down or breech open and transfer port at lowest point to allow for the excess oil to be removed.

                      I don’t know if the QB-36 has the ability to diesel or detonate due to compression heat as I am not that familiar with the gun, but if the air chamber does have liquid oil in it and it is fired I am pretty sure it could do damage of some sorts if not break the spring due to hydraulic lock.

                      Buldawg


                    • Bludawg,

                      You make it sound like Reb has filled the compression chamber with oil, instead of just using a couple drops. Is that the case? If so, the rifle needs to be taken apart and the oil cleaned out.

                      You don’t fill the compression chamber of a spring gun with oil and then attempt to shoot it.

                      If he has just used a few drops, though, your fears of “hydraulic lock” are unfounded.

                      B.B.


            • Here’s a discussion I encountered during my search:
              http://www.gatewaytoairguns.org/GTA/index.php?topic=37580.0
              But the one I had for $18 was direct from the spring man., free of brackets and adapters.from the list found in this discussion:
              http://www.gatewaytoairguns.org/GTA/index.php?topic=37580.0r coding but when I had to start with Newton/meters to calculate expansion rate I ran outta steam.That’s something I need to learn how to work with before I check again.

              Reb


              • Reb
                That is some good info for sure and I believe I need to take my gun apart first to see if the rear seat and or front are the same as what’s in mine or do some more research on the parts.
                I did not think about the piston having a seat to hold the gas spring rod centered or the rear seat for the ram also, so I need to check those part numbers out also.

                The links you gave me are both the same and I did not see any added material in the second link, I did not watch the video on how to make a spring yet but I saved the link in my favorites for later.

                The one you found from the spring man is that his site name or what is his site name or what do I google for his stuff.

                Buldawg


    • Depends upon how you view things…

      If a pellet is blowing all the way through the target, then it is wasting energy that was not transferred by doing damage to the target. A pellet that does not penetrate completely has spent all the kinetic energy in the target.

      This goes back to the old 9mm Parabellum vs .45ACP arguments (back when round-nose jackets were the norm). The 9mm is a fast round, but tended to penetrate through with just a small whole; the .45ACP runs 400FPS slower (or more) but transferred more energy to the target rather than penetrating through.

      Now that modern hollowpoints are available for all, the 9mm is less likely to penetrate completely, and transfers more energy in doing tissue damage.

      As for ranging… Plug your numbers into something like ChairgunPro — then determine what you consider the minimum energy level /at the target/ you feel is required for a good kill. That will define your range.


      • What will Chairgun pro do?

        That will only give you a reference to what range your shooting at. And if you made the right choice of pellet to fall in that estimated range you want to be accurate in.

        FPE is what you need to know for that distance to dispatch that animal.

        Chairgun will only help you know how to hit the intended target/animal. It doesn’t know how much that animal weighs or how much mass the projectile has to go through.

        I haven’t heard of a good way to estimate if a pellet will pierce through a certain mass at a given distance.

        Please tell me. I will try it out as soon as possible.


        • Chairgun /will/ (or did — I need to check the current version in more detail) give you the remaining energy at distance for a specified pellet and velocity.

          Now, how much do you need for your victim? That I can’t say. Think I saw one page that specified around 5ft-lbs for squirrels, and I presume that is terminal energy, not muzzle.

          I’m not linking the site (though I don’t think it’s a direct competitor — Google “airgun hunting energy” should bring it up) but…

          The energy of a hunting rifle pellet should be at least as high at the target distance (pest birds for example) as target airguns are at the muzzle (4 ft.lbs.).

          Grackles and other pest birds require one-inch accuracy at 20-30 yards. Grey tree squirrels require similar accuracy, but at least 8 ft.lbs. of energy at that distance. Crows require two-inch accuracy at 40-60 yards, the same as wild woodchuck, but the chucks require 10-15 ft.lbs. of energy at that range, the crow only half that. Suburban woodchucks can be approached to within 30-40 yards, so a less powerful rifle may do.

          Don’t get many grey’s in my area… The fox squirrels are almost twice the mass, and likely want higher energies.


          • Wufraed
            I will have to check and see if the Chairgun program I have will show retained energy. If so that will definitely be a aid in estimating the power needed for a given distance.

            That’s the thing if we were to say that it just so happens to take 12 fpe to dispatch that red squirrel the gun will need to be making more at the muzzle. That would be a very smart thing to know when hunting with a air gun. That way you would know the limit to your combination.


            • I just loaded the program, and expanded the ballistics table pane. Retained energy is one column.

              Now if I can just find where it saved the file when I told it to save as CSV… It supposedly saved a “test.csv” but a search of my computer isn’t finding it (ah well, save it again picking a known directory)

              Profile GA
              MV 790 (ft/s)
              ZR 35 (yard)
              BC 0.021
              SH 2 (inch)
              AmbT 20 (deg C)
              AmbP 29.95 (“Hg)
              WindS 0 (mph)
              WindA 90 (deg)
              Incline 0 (deg)

              Range POI Velocity Cd Drift Time moa Clicks Energy Mom.
              (yard) (in) (ft/s) (GA) (in) (sec) (moa) (clk) (Ft.Lbf) (Grnf.s)

              0 -2 790 0.203 0 0 inf inf 11.6 206.279
              5 -1.23 767 0.2 0 0.019 -23.4 94 11 200.243
              10 -0.6 745 0.197 0 0.039 -5.7 23 10.4 194.553
              15 -0.13 724 0.195 0 0.06 -0.8 3 9.8 189.046
              20 0.18 704 0.192 0 0.081 0.8 -3 9.2 183.781
              25 0.31 685 0.19 0 0.102 1.2 -5 8.7 178.746
              30 0.25 666 0.189 0 0.125 0.8 -3 8.3 173.864
              35 0 648 0.189 0 0.147 0 0 7.8 169.147
              40 -0.46 630 0.189 0 0.171 -1.1 4 7.4 164.535
              45 -1.14 613 0.189 0 0.195 -2.4 10 7 160.077
              50 -2.04 596 0.189 0 0.22 -3.9 16 6.6 155.726
              55 -3.2 580 0.189 0 0.245 -5.6 22 6.3 151.484
              60 -4.6 564 0.189 0 0.271 -7.3 29 5.9 147.391


              • Wulfraed
                What program did you load. Is it Chairgun pro or do they have a newer version now?

                And I don’t think I see how much the projectile weighs.

                And one question when the numbers start showing zero and minus numbers on the retained fpe is that were the projectile starts falling on the graph. At what distance does it stop making negative fpe? Maybe I’m looking at that the wrong way.


              • Wulfraed
                Never mind. I was looking at the wrong numbers for the fpe. All the numbers are trying to run together on me.

                I see it started at 11.6 fpe at 0-2 yrds. and ended at 5.9 fpe at 60 yrds.

                Very useful info that’s for sure.


  19. Edith,

    I’ve had a number of problems posting comments, some of them quite lengthy, on Tuesday and today. Some of the stuff seems to go through, but does not show up. Some of the times I’m getting a 500 internal server error message. Can you check and see what’s going on.

    J.


    • J.,
      Have you set up your gravatar account yet? If so you don’t have to do the math problems
      Go to the upper right hand corner where it says “Howdy” I can’t remember the whole process.I do remember it took me quite a while before I finally got my Avatar.


  20. This will be a great article series! I’m especially interested in how the shooter chooses the right weight of bullet to match the twist and power of his airarm. When shooting black powder I learned that round and conical projectiles could both be sent accurately from my fast-twist rifle, but with very different powder charges.
    Also, it doesn’t seem like defining which bore is “big bore” really suits this discussion. It seems we would be better to define the threshold of high energy or Hi-E airguns.


  21. While I don’t compare it to the shock wave generated by supersonic ammo hitting soft tissue, I have observed a definite hydrostatic effect on small game with airgun pellets. I noticed it with my Benjamin Trail NP2 in .22 and it’s even more pronounced with my Hatsan BT65 in .25 (more power, bigger hole).

    When I land a head shot on wood chuck size game, the hydrostatic shock frequently blows out the membranes in the sinuses and eardrums causing immediate and heavy bleeding from those orifices. Sometimes one or both of the eyes are blown out of the sockets as well. And this is with non-expanding round nose pellets.

    That is the main reason I try to exclusively take head shots. I feel fairly certain that an internal pressure which blew a critter’s eyes out must have also scrambled the brain and resulted in an immediate and painless death.


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