This report covers:
- Measuring group sizes
- Safety with CO2
- Lead in the barrel
- Repeaters and accuracy
- Rotary magazines
- Chain magazines
- Summary
In the past few weeks we’ve had some questions that tell me there are some basics we need to brush up on. This may not be a helpful report for many of you but please bear with me. For others I may not touch on the one thing you’d really like to know. If I miss it please ask.
Measuring group sizes
When we measure shot groups we do it from the centers of the two holes that are farthest apart. And please forget trying to guess where the centers of the widest holes are and placing the jaws of the caliper there. That adds a lot more ambiguity to your measurements.
This group measurement is a convention that has been passed down in the shooting sports. Those in the USA will no doubt measure in inches and the rest of the world will measure in millimeters, but other than that, we should all be doing it the same. So, how do you do it?
You measure across the group until you find the widest dimension, then subtract one bullet (or pellet) diameter. One diameter is comprised of two radii, so what you have done is subtract one radius from either side of the widest group dimension. That measures from the centers of each hole.
Measure from one side of the group to the other side and subtract one pellet diameter.
Guess what? You can’t measure groups to the thousandth of an inch. You can’t. I can’t. Nobody can. But I always give you group sizes in thousandths. Why? Because the digital caliper that I use to measure the groups reads out in thousandths. You will always be off by as little as 0.005 inches and as much as 0.020 inches when the holes are clean like these. The holes shown above were left by wadcutter target pellets. Most groups look more like the one below.
Now find the edges of the holes! This is what domed pellet holes look like.
And sometimes it gets worse than that.
This is what slow-moving BBs do to a target that’s been attached to a cardboard backer. Guess where the holes are? I need a vacation!
I’m sure many of you knew this already and didn’t need to be reminded. But from some of the comments I’ve been seeing recently, I was concerned that some of us are getting hung up on the numbers — as in accepting them at face value. These numbers are a best guess and are published with the best of intentions, but they are, and always will be, a little off.
Here’s what you can say about such numbers. A 0.36-inch group is unquestionably tighter than a 0.511-inch group. Even when the first group is shot with .25-caliber pellets and the second is shot with .177-caliber pellets, so while the two groups appear very much the same on the outside, the first one is still tighter.
Safety with CO2
Some of you are new to CO2 gas. It has a vapor pressure of 854 psi when the temperature is 70 degrees F (21.11 degrees C). And CO2 sublimates. That means it will change directly from a solid to a gas without passing through a liquid state. So, drop a chunk of dry ice (solid carbon dioxide) into a pressure vessel at 70 degrees F, seal the vessel and it will evaporate until the internal pressure either reaches 854 psi, or, if the vessel is small enough, the remainder of the solid CO2 will turn to liquid. As the pressure is released from the vessel, some of the liquid that remains will evaporate to gas and the internal pressure will remain fairly consistent.
Now, that explanation is not entirely accurate. CO2 is a refrigerant gas. As it evaporates it also draws heat from whatever it touches, so it is next to impossible to maintain 70 degrees F in a pressure vessel with gas going in or coming out. But the gist of what I described holds true.
That is why you can’t unscrew the cap on a CO2 gun when there is pressure inside. The pressure that remains pushes the cap’s o-ring seal against the internal walls with hundreds of pounds of force — making it seem like the threads of the cap have seized. I have seen end caps that have had their knurled edges worn away by the jaws of vise grips because someone didn’t know that. Luckily for them, the cap didn’t come off!
As the temperature increases the pressure of the gas also increases. At 70 degrees it is about 850 psi. At 140 degrees the pressure rises to well over 5,000 psi. The actual pressure depends on several things that are interrelated, but suffice it to say a CO2 gun left in a hot car on a summer day can blow out the car windows!
I also know a man who once tried to solder his CO2 pistol when it was charged. The explosion taught him an important lesson and, since it left him alive, he learned something.
Lead in the barrel
I showed this picture in the report on the FWB 127.
That picture was accompanied by this caption, “That breech seal is shot. There goes a lot of velocity! The bore could benefit from a deep cleaning, too.”
That bore has large deposits of lead. It remains in the grooves but not on the tip of the lands because each new pellet scrapes that part clean. The lead is why the grooves are light gray. You can’t see it, but there is probably a coating of lead on the sides of each land, as well.
Does it matter that the bore is leaded? Only if the accuracy falls off. Reader Kevin surmised that someone had probably shot a lot of Crosman Premiers in the 127, as they were the darlings of the day. Crosman pellets are made from an alloy that’s high in antimony and antimony will cause lead to scrape off like that.
I don’t typically clean the bores of my airguns unless there is a drop in accuracy. Sometimes I’ll get a gun from the Orient whose barrel needs a cleaning before it’s fired for accuracy. If I test an airgun that starts out inaccurate I will sometimes clean its bore. You readers often remind me to do that.
Repeaters and accuracy
Single shot rifles and pistols are the more accurate than repeaters; there is universal agreement on that. The most accurate benchrest rifles are all single shot. Those are the rifles that weigh 60+ pounds and are really just shooting machines.
When it has to be accurate, this is what you do. No magazines in this one! No stock, either.
But often the difference in accuracy between a single shot and a repeater is so small that it goes unnoticed or doesn’t matter. But there can be a difference and it pays to know why that is.
Rotary magazines
The most popular magazines for repeating pellet rifles today are rotary mags. They usually work well but can have problems when the pellet carrier inside the mag doesn’t quite align with the bolt, or the mag cover or the breech or all three. If that happens the pellet can be slightly damaged when it enters the beech. If the rifle is accurate you may shoot a group that always has a couple fliers. Avoid shooting that/those particular pellet(s) into the group and the flier(s) will stop. What I’m saying is you may notice that shot number four is always a flier. So shoot shot 4 somewhere else and leave it out of the group.
Chain magazines
Chain magazines have the same alignment issues as rotary mags, and more of them because the tolerances have to be larger for the chain to function. The solution is the same — avoid that/those shot(s).
Any other magazine that can cause misalignments of the pellet when feeding can be an accuracy issue. The solution is to try to shoot the same airgun single shot to see if there is a difference in perceived accuracy.
Summary
There are four issues I have noticed in the comments in recent weeks. If I didn’t address your issue, please raise it in the comments.
Tom,
Thank you for the review of some shooting basics. Is there going to be more parts to this? I feel there are more to come touching on looking for the best positioning of the airgun in relation to the rest especially in springers or the importance of follow through and being level with the target? And as always the key to consistency is Practice, Practice and Practice by dry firing and actual shooting.
Siraniko
Siraniko,
I suppose there could be more parts, but I need to hear from the readers.
BB
I like using heavy card stock targets for shooting groups. My old rifle club club used targets from Targets online in heavy card stock, these targets were easy to score and they hold together on rainy days. Kinda pricey but worth it. Dividers for hanging file cabinets(remember those ?) make great home made targets that show clean holes.
My humble PCP collection consist of two Origin’s .22.and .25 also two DAR rifles a Gen 2 in .22 and a Gen 3 in .22. The Origins and the Gen 2 DAR shoot very well with magazines but better with a SST. The Gen 3 DAR shoots terribly with mags(I have tried five different ones) but is a world beater with a SST. The DAR mags are among the very best, something is just off with my Gen 3 but it shoots so well with the SST that I would not dream of returning it to fix the mag issue.Anyone that owns a rotary mag rifle that did not come from factory with a single shot tray should purchase an aftermarket one(Pyramid has them for most PCP rifles) it is well worth trying.
SSC,
I am somewhat envious. I have always wanted an Origin in .22. The DAR has on several occasions drawn my attention also.
I have avoided buying any Wang Po Industries airguns for quite sometime now, but I may end up with that new Zelos/M60 this year. It is going to be difficult to stay away from that Avenge-X also.
I have been shooting single shot most of my life. Even when I was into powder burners, many of those were single shot. Slow down. Take your time. Make each shot count.
Amen Ridge. These days most of my PB shooting is done with Rolling Block rifles and Flintlock long guns and bolt .22 target rifles. No need to rush anything. PS , I really am impressed with my Origin rifles, the .22 is for fun and the .25 is on armadillo patrol. For the money the Origin is hard to beat, it is a close cousin to the Avenger.
SSC,
Now I am really envious. I used to have a Pedersoli rolling block in .45-70 and I long for a flintlock long rifle to hang over my fireplace.
BB,
As you may have noted I’m getting ready to try and get the most accuracy out of a few new airguns, AKA Target Shooting, and a lot of old new ones I have and have ordered the MTM shooting table and rifle rest to assist me.
It bothers me that most of the time it is a matter of trial and error, or luck, to find the best way to hold the airgun or rest it. Insert a pellet or deep seat a pellet and of course which pellet works best in any given shooting situation, high or low power, near of far, heavy or light, and desired impact.
Is there any procedure established or information available to start the process of getting the most accuracy possible with any given airgun. For example, do you find the best hold or the best pellet first?
What procedure would you follow to find the best hold? Use the same pellet throughout the process?
In other words, is there any priority to which information you acquire first. Find the best way it likes to shoot or the best ammo? Would hate to test 10 different pellets only to find out the airgun shoots much better being held tight later on and all the information you documented on each pellet is now off.
I am inclined to use a pellet with a good reputation for accuracy and shoot groups with the airgun (rifle) in every possible hold first, same with bipod and resting, and then look for the best pellet for every use. Or would every pellet prefer its own hold? Scary thought there.
Would it be better to shoot a bunch of pellets through it first just to break it in? A hundred or more? Any pellet type recommended to do that? No rush here for answers. A blog perhaps?
Any recommendations would help speed things up.
I don’t think any of mine have that many pellets put through it yet.
May be making a mountain out of a mole hill, just looking for the best way to find each rifles best accuracy possible, as soon as possible. Preferably establishing the rifles capability without human (my) interference first. Just to see if it’s my fault later. Like a shooting machine. OR, do some rifles actually shoot bad when locked down?
Bob,
Wow!
Is there a quick approach to finding out the accuracy or potential accuracy of an airgun? My first inclination was to answer — I wish there was! But that was before some thought that I am now applying.
Sort answer — I don’t know.
Better answer — I’ll think about it.
Best answer — it sounds like a good blog.
BB
Bob,
You need to find the right hold of the rifle first.
-Y
Yogi,
Thanks. Yes, that seems to make the most sense. There is just so much that affects airguns.
Just today shooting the BM8 I tried deep seating the pellets and increased the scope magnification from 3x to 4x and it moved the grouping almost a full inch higher at a distance of 36′.
I’ve decided to forego seating pellets except under unusual or necessary circumstances. For example, my vintage Dianas have a very slanted breech that distorts the skirts. Others are so low powered that the pellet seems to benefit from a head start. Other springers don’t have those problems. When hunting, I don’t want to have to spend the time if a quick second shot is needed. Hunting guns should shoot well enough without a lot of fiddling around, in my view.
IMHO (In My Humble Opinion), on an airgun that you have just received (old or new) you need to clean the barrel first, snug all screws/fasteners second, shoot several hundred shots at least (to break in all parts in a springer and break in the regulator on a pcp and adjust the trigger to your liking) third, and then move on to the other 20 things, including finding the right hold, to be able to wring out all potential accuracy in your new to you airgun.
Kevin,
Are you trying to get new airgunners to quit the hobby? ;^)
Michael
Bob M,
what a great question !
I like Yogi’s reply, and, look forward to B.B. Pelletier’s more in depth treatise… 🙂
If only airgun makers were to include how they managed to achieve their best accuracy… but, I guess, a comprehensive Manual is yet to become fashionable, eh? 🙂
3hi,
Most of the manufacturers do not bother to see what the accuracy of a given airgun is. If for no other reason, there are just too many variables involved, including those in the manufacturing process. Please do not hold your breath waiting for that manual.
RidgeRunner,
thanks for your concern. My giddiness stems not from holding my breath but from the vertigo, up here on this soap box ! 🙂
The way I see it, a manufacturer’s motivation for a comprehensive Manual is matched by the consumer’s motivation for reading it, you know, almost as if they include some sort of information to barely satisfy a legal requirement but no more because they know that next to nobody will read it anyway.
Therefore, if we, the potential customers, were to give the Manual more importance, possibly even to deal breaker level, then the makers of things might respond.
————
This reminds me of an example for useful information: the Manual I got with my Pietta-made muzzleloaders suggests black powder loads and projectile sizes. 🙂
Pictured below is such a page, ie page 18 of Pietta’s “Black Powder Muzzleloading Revolvers And Carbines” Manual…
3hi,
Some of the airgun manufacturers do indeed invest more in their manuals. I have seen some that were very specific to the particular model and very detailed. Mostly with FWB and their 10-meter airguns, but some others have even included a sample target.
Of course, in some manuals the manufacturer will recommend that you buy their pellets. That I never do. Overall, as I stated before there are too many variables involved for the manufacturers to include their recommendations for best accuracy and as that would just likely be another marketing ploy, no one with experience is going to listen to them anywho.
Bob M,
Yogi is off to a good start. BB writing a blog about how he approaches shooting a “new” airgun would be a better answer. If you read through a bunch of BB’s blogs, you can get many clues there.
In my “collection”, one of my air rifles likes RWS Superdomes, another likes JSB Exacts, another likes Ely Wasps, another likes … See where I am going with this. Each one of these gals has her own dance. Even two twin sisters will dance differently. It is up to you to study her and learn how she likes to dance.
The best thing I can think of is to hold that gal a certain way and she how she does. After a bit you learn to hold her a slightly different way and see if she does a better dance. Once you learn what is the best way to hold that gal, you start feeding her a little different and see how she dances then.
All the while you are learning how to hold her and what she likes to eat, you will be teaching yourself how to dance with her. If you dance with her enough, you will know how to do such without even thinking of it.
Don’t get too hung up on thinking about it, just go out and dance.
Bob, with a new airgun, I like to give it a good look over first. Sometimes you can see junk in the barrel from manufacturing. That definitely merits a cleaning. More recently, I’m of the mind that a good cleaning with JB Non’embedding Bore Paste goes a long way toward breaking in a new barrel.
In your case with the BM8, it’s a survival rifle, and you will use it for pesting, so domes or hollowpoints are your choice of pellet over wadcutters. I would start with the cheapest domes you can find, just to do breaking in and experimenting with different holds. Once I find a good hold, I can start with different pellets. I found generally once I find a good hold, most pellets will shoot best with that hold. I generally like to start with my hand on top of the sand bag, open palm, artillery hold right where the gun will balance. Sometimes that’s close to the trigger guard, sometimes that’s further away. Then I will try a bit further away or a bit closer to the trigger guard if possible. On the trigger hand, sometimes where you put your thumb will have a great effect. I start with my thumb alongside my index finger. Only change one thing at a time and keep notes as you go along.
Once I think I have a good hold, by then the gun is well on its way to breaking in, and I am well on my to getting to know the trigger and shot cycle.
Then I’ll try a pellet that perhaps B.B. has used on the blog with good results or pellets I have confidence in, and go from there.
B.B.
Always good to review the basics!
-Y
B.B. Pelletier and all commenters!
I really enjoyed reading today’s blog because it is wonderfully written.
And I think I know why that is: almost
N O . A C R O N Y M S
, Hurrah! 🙂
Every bureaucracy needs a DONA – Department Of No Acronyms – hihihi.
FawltyManuel,
GAS 2U!
DQMOT, BSF IDK WCA 2TXT W/LOA.
IYO, ITS EZ &PDQ… IDTS.
IMHO, ARE =ADIH. TBH, FUBAR &2M2H. GIAR, PLZ! KISS.
.02
RX
🙂
FawltyManuel,
Translation:
Greetings and Salutations to you!
Don’t quote me on this, but seriously folks I don’t know who cares anyway to text with lists of acronyms.
In your opinion, its easy and pretty darn quick… I don’t think so.
In my humble opinion, an acronym rich environment is another day in hell. To be honest. its *fouled* up beyond all recognition and too much to handle. Give it a rest, please! Keep it simple, stupid.
Just my two cents.
Regards,
———-
I wish I could remember where I got the acronym message from. I think it was some professor who thought to make a point in this manner.
———-
Anyway, I think it’s clear that acronyms and abbreviations are always for the benefit of the author, not the reader. 🙁
Good information, thanks BB. And Bob’s questions are interesting. I am just a novice but have learned a lot already. For what it is worth, it seems to me that choosing the equipment (including guns, pellets, sights & optics, rests, etc.) is daunting due to the number of choices available. Perhaps defining your goals might be a proper starting point. What type of shooting do you intend to do? Ten meter paper targets or long range target shooting or hunting or plinking, etc. Defining your goals might help rule out some items (including some pellets). Also, I think learning to enjoy the process of testing is important. We all get anxious to “get there.” However enjoying the journey can be a lot of the fun (if you have the proper mind-set).
Elmer,
IMHO, all guns are “tack drivers” …within their effective range. That range might be measured in inches, feet or yards. The other thing to consider is how big is the “tack”. 🙂
I’m kidding and I’m not. You are right in that the discipline dictates the (accuracy, distance, power) requirements. The first task is to match the right tool to the job… which is the reason we need lots of airguns 😉
Totally agree with your comment that the journey should be fun, unfortunately sometimes people loose sight of that. That’s why I’m a casual shooter and plinking is my favorite “discipline”.
Cheers!
What he said!
Elmer,
Very true. “What do you want it for?” The only problem then is ” Which one that fills that need do I get?”
If you were only getting one it would be very important.
If you want one for every need you may be in trouble and verity is the spice of life.
When I get too old, I hope to thin out the collection to the precious few. Unfortunately, each one is precious in its own way and at this point … You are usually addicted. In a good way of course.
Thanks BB!
Revisiting basics is always a good idea. That is why teaching/mentoring a such a good thing for both the newbie and the instructor… to remember what we have forgotten.
Hank
What FM has learned on the road to airgunnery is not to get too hung up on perfection, otherwise it takes the fun out of the whole process. When it comes to grouping shots, figuring out the best hold etc etc, his personal goal is to get to “good enough for FM” level or results. That comes thru learning one’s limitations and accepting them. Realize that if you are going to be a serious competitor and/or hunter then you need to work at doing your best and going more in the direction of getting as close to “perfection” as possible. Still, emphasis should be in the enjoyment of the sport, not in falling into the hole of frustration while trying to achieve the impossible.
And, as says Siraniko, “the key to consistency is Practice, Practice and Practice by dry firing and actual shooting.” The “dry firing” part is not for “sproingers,” though.
BB-
I think maybe you should address-
Precision vs accuracy
Group shape as both indicator and diagnostic aid
Thank you and almost halfway through February!
PO,
Very good! Those two points alone would make two superb blogs!
BB,
It looks like you are already off to a good start with some of these suggestions. As is obvious to everyone here, I too could stand a little refresher course. We all could stand to read this “series”.
Well, according to my pill thingy it is Wednesday morning and I guess it is still February. I just looked on my calendar and found out today is the 14th. It says today is Valentine’s Day. I had better wish Mrs. RR a Happy Valentine’s Day when she gets up.
Retirment sure is a bummer. 😉
Just to add a couple of tips to the conversation:
1-Cereal boxes make nice targets. +’s can be drawn using a ruler and circles can be drawn using washers and tape dispensers. The +’s eliminate cant. The reverse sides of cereal boxes give good contrast to permanent black felt pens.
2- Open sights are fine if the front sight is in sharp focus but peep sights are better.
3- Scopes let you see where your shots are landing.
4- Deep seating pellets in accuracy testing has fallen out of favor in my opinion.
Deck
As an added bonus, you can tout yourself as a “cereal killer.”
FM
Yeah cause every box is done for twice.
D3ck
I’m convinced that many of the readers of this blog rarely, if ever, comment. I also believe that most stumble their way here because they either have an airgun that has caused them frustration and/or want to buy an airgun and don’t know what to buy. Most buy a springer as their first airgun. Then they return to this blog to learn how to shoot it accurately.
With rare exception, folks buy an airgun and can’t figure out why it’s not accurate (I remember someone buying two Air Arms TX 200’s as their first airguns but that was an exception). I am sure that B.B. discovered the Artillery Hold with his Beeman C 1. The Artillery Hold is now common jargon on all airgun forums.
B.B. often talks about it and sometimes shows variations of it but it should be a part of all airgunners skill set. Here’s a good article that makes the point:
https://americanairgunner.com/shooting-a-spring-piston-air-rifle-for-dummies/
kevin,
thanks for that link. I like the included pictures that illustrate various holds and resulting groups of an air rifle that is spring powered and known to be precise (Air Arms TX200), proving the artillery hold is best (have yet to watch the video). 🙂
B.B. and Readership,
I think Yogi, Kevin, Elmer Fudd, Vana2 (Hank,) pacoinohio, and Michael have all given you excellent grist for your blog mill.
I will add one which i think is the first thing among first things:
Is your gun working to at least near to the manufacturer specification?
Why bother with an obvious LEMON!
BUT…how does the new to airguns shooter know to suspect their purchase is a LEMON that needs to be returned.
What are some of the most common and obvious reasons by powerplant?
shootski
I found when shooting domes, that a thin layer of duct seal on the back of the target paper allows domed pellets to make wadcutter-type holes. I take a ball of duct seal about an inch in diameter and flatten it into a thin pancake (a small, grey crepe, if you can imagine. Tortilla chip thin. That sticks right to the back of the target paper behind the bulls eye. Makes perfectly measurable holes. What’s left gets rolled into the next ball for the next target.
B.B., I must say congratulations. For a seemingly basic blog today, the readership has shared an amazing array of advice. Thank you all for your collective wisdom. Moving on to world peace…. ;o)
Sorry for dropping out here, went to sleep at sunrise here in CA. Your early morning is usually my late night.
Been wanting to behave like that since I was 5 and had to get up for school. Must be part Vampire. 😉
A born night person. Back soon. When I get into something I don’t want to stop sometimes. And that includes sleeping !
Lots of good advice, thanks.
My main reason for asking was to save time and avoid the trial-and-error period. A nice step 1), Step 2) and so on would help.
I really do not shoot my springers enough to get familiar with them and this was mainly to address them.
As for deep seating pellets, don’t know why I did it with the BM 8, yes, I do remember.
It was hard to seat the pellet flush and I did not want to distort it.
Not sure why it raised the point on impact by an inch or so, but I would guess that the pressure that builds up behind the pellet when fired was reduced because it did not have to overcome the friction of the expanding pellet skirt engaging the rifling. And that was hard enough without it expanding and simply inserting it.
The reduced pressure build up may have reduced barrel droop?
Something to look into perhaps?
Interesting discussion above. I’ve gotten breaking in new air rifles to a few tried-and-true steps that I follow every time another piece elbows itself into my crowded arms locker:
1.] I get out the J&B Bore Paste and clean the bore with a couple of dozen back-and-forth strokes with a well-coated bronze brush.
2.] That is followed with felt pellets PUSHED through the bore from breech to muzzle until pretty much “clean.” I then oil up four or five with Sheath/Barrier and PUSH them through with my Breechway flex rod (wiping the rod clean between pushes). When the barrier gets the residual OUT of the barrel, I push a couple of dry pellets through to sop up the Sheath/Barrier oil
3.] I shoot a tin of cheaper wad cutters without worrying about attaining great accuracy. I use that time to find the hold for the piece that seems to work the best. After a few hundred pellets, it then is time for accuracy work.
4.] Putting in premium pellets, the work then begins on refining the hold, making a decision to use or not use the pellet seat tool to “click” the skirts into the rifling. I keep a marked 12 bull rifle target with each bull recording date, pellet type, and any sight adjustments, and the sequence number That allows me to see if there are any trends that the piece is producing in the chain of bulls.
5.] After the initial tin or two, any optics added are affixed and tightened down (along with stock screws) and the process of zeroing them in begins. That is done with very little, if any, click adjustments on the scope or peep to start. Need for radical adjustments are negated by shimming FIRST – especially on scopes. Turret adjustments are withheld until the piece is nearly on the 10 ring.
6.] With the air gun now breaking in, refinement of sophisticated sights and hold can proceed to refine the accuracy potential of the new piece. Other types of pellets can then be introduced to see if increased accuracy accrues. Usually pellets changes are accommodated by reasonable turret adjustments.
7.] I read the P/A Blog consistently as well as P/A reviews for any mention of oversize or undersize bores encountered by contributors. Also, I pay attention to rereviews of pellets as being over or under sized. I then seek to match these integers together. For example, Hatsan’s .25 bore is oversized so JSB Monster Mark IIIs (which are oversized) make a wedded couple and work perfectly TOGETHER – the experience of other seasoned shooters can be headache prevention!
8.] After use care is paramount with my arsenal. After a shooting session, all metal is wiped down with Sheath/Barrier by Birchwood Casey. As needed, another layer of Minwax on wood stocks is applied before the piece is set in the arms locker to dry down for later buffing.
9.] My springers get 3 drops of Diana Air Chamber Lube, in the compression chamber, after every second 500 ct. tin of pellets and all hinge points with Spring Chamber lube.
10.] Barrels get cleaned and a thin coat of Sheath/Barrier applied at any fall off of accuracy AND before I shut down my basement range in favor of cycling season. In case of the latter situation, I do NOT remove any excess Sheath/Barrier but let it remain in the bore as a rust preventative.
=============================================================================
So far, this “routine” works for my armada of air guns. Since they are stored in a finished basement, it is good that they are always coated against oxidation, and they certainly look better all shiny and clean!
Regarding the alloying of lead for pellets, I sent three samples of fresh pellets to a lab for analysis by emission spectroscopy in 2021, to see just what metallurgy was found. These were H&N, JSB, and Crosman pellets. In my career, I routinely sent samples of solder for this type of analysis, so I knew who to contact.
Based on those results, the common approach is to use high purity lead, with small additions of antimony. This is done to make the lead more easily swaged.
There is a vast amount of information about lead alloying for cast firearm bullets, and this relates both to the desired properties of the bullet, and sources of lead. Hobbyists have difficulty getting high purity lead. But importantly, hardness is not a desired property for shooting in air rifle barrels with low hardness steel rifling.
Antimony at the levels used for pellets moderately increases hardness, but this is only as cast. Small amounts of antimony in the 0.4% range are below solid solubility, but they do increase both the work and age hardening of the alloy by refining the grain structure of the solid solution. My research indicates that hardness over a period of years will slowly increase, even for 0.4% antimony (the solid solubility limit).
If I was specifying the amount of antimony, that would be my alloy. Adding more will mean that the cast alloy is somewhat harder, but it won’t do any more for the “machinability” of the alloy. Without the small Sb addition, pure lead is “mushy” and very likely more difficult to punch or swage – but any harder, you’d see more wear in your tooling after a few million cycles.
I believe the hardness of pellets themselves after punching (JSB) and swaging is probably a good deal higher than the BH8 of Pb-Sb. I’m thinking of ways to check that, but nothing so far without elaborate equipment, and I think it needs to be done directly on the finished pellet.
Cast lead bullets usually get antimony (or tin) by way of using old Linotype or wheel weights, which typically have 1-2% Sb added. Lead-acid battery plates also had antimony, but this has been mostly discontinued as removing it helps to make the battery “maintenance free”. Linotype is not as plentiful as it once was.
There are other ways to harden lead, but this 0.4% addition is probably the most efficient way to improve the results of pellet manufacturing.
And, I believe that the results of this emission spectroscopy testing show that there are small antimony additions for H&N (0.38% w/w) and JSB (0.20%). All samples were high purity lead, a good thing. Crosman Premier pellets were found to have 1.26%, which would certainly increase hardness somewhat.