Hand pumps for the ancient big bores: Part 1

by Tom Gaylord
Writing as B.B. Pelletier

A history of airguns

This report covers:

  • How powerful were antique big bores?
  • How were they filled?
  • No one knew
  • Hand pumps of antiquity
  • Empirical testing
  • Early rapper
  • Single-stage pump tradeoff
  • But wait — there’s more!
  • Summary

Dennis Quackenbush has always been helpful when it comes to the difficult questions about airguns. Over the years, he and I have experimented with several fundamental questions; the most recent being the $100 PCP. I should have an update on that one for you in a couple weeks.

How powerful were antique big bores?

Back in the 1990s — the days when I was still writing The Airgun Letter and Airgun Revue magazine — I had a prolonged discussion with Dennis about the performance of big bore airguns of antiquity. He had just come out with the .375-caliber Brigand that was about to start the airgun world on its modern journey toward big bores, and there was a lot of interest in them.

This report is not about big bore power, but the hand pumps that were used to fill them. I did write a blog about the power of big bore of the past that can be seen here.

How were they filled?

I wondered how powerful those old airguns were, and also how they were filled with compressed air. On Monday of this week I published the report on the air cane and one of our readers wondered the same thing. How could anyone fill an antique big bore airgun with air compressed high enough to launch a lead bullet with lethal force? There were no scuba tanks and no shoebox compressors back in those days (1600s-1900s). Indeed, there weren’t many devices that could compress air at all, to say nothing of the relatively high levels that were required by an airgun!

They didn’t even call them air compressors back in the 1600s. They were called condensing syringes, and compressed air was called condensed air. The terminology had yet to be established.

No one knew

It seems strange today with all that we know about big bore airguns, but in 1997 almost nobody knew how fast these old guns shot or what sort of pressure they used. I read all sorts of guesstimates of velocities up to 1,000 f.p.s. for the antique big bores.

Eventually splatology (the determination of terminal velocity by the shape of a deformed lead ball after hitting a hard surface) was developed by Gary Barnes, but Barnes came to the party in the late 1990s, and these questions were being asked several years earlier.

Hand pumps of antiquity

One thing we did know about the vintage big bores, though, is what their hand pumps looked like. Many of them survived along with the guns, and they were usually in better condition than the guns themselves.

I had examined antique hand pumps several times at airgun shows. They always operated very smoothly, like their pistons had been lapped. I saw the insides of a couple pumps and neither of them had a piston seal. They had a flat iron piston head on the end of the pump rod. A light to medium weight oil (like 3 in 1) was squirted into the pump before it was put into operation. Oil on the compression chamber walls did all the sealing — similar to how it works in an automobile engine.

I have read several accounts of hand pumps that have leather piston seals. They were either a single leather seal covering the end of the piston, or they were a stack of leather washers fastened together at the end of the piston. These presumably work the same way as the plain metal pistons, plus the leather helps keep oil on the walls of the compression chamber. I only know about the stacked washer type from reading Air Guns by Eldon Wolff. He admits that the leather washer type is much rarer than the plain piston type. But how effective were they? What sort of pressure could they generate?

Empirical testing

I asked Dennis how much pressure a common single stage hand pump could generate. He’s been making replica hand pumps for vintage big bore guns for several years. Dennis’ pumps are true to the old designs, except that they use synthetic pump seals. He suggested that we test some pumps and find out.

Before we conducted the tests, it seemed to both of us that neither vintage pump design (plain piston or one with a leather seal) could equal one with a modern synthetic seal. Whatever pressure could be achieved with a modern replica would probably represent the absolute maximum for any vintage pump of the same physical specifications. That turned out to be an incorrect assumption.

Early rapper

We both agreed that the practical limit to the force that could be applied had to be the weight of the person doing the pumping. These early pumps had no mechanical advantage beyond that which is inherent in a single-stage mechanism. Although it would be possible to generate more force than one’s weight by pulling the base of the pump toward oneself, it isn’t practical — and would be very hard to do on a continuing basis. Jumping on the pump handle, however, is actually a method that was used sometimes. It was called rapping, but it’s very hard on the hands, wrists and arm joints and you can’t do it very long.

Single-stage pump tradeoff

Okay — remember when Mr. Conners, your 8th-grade math teacher, told you that one day you would need to know geometry? Today is that day. A single-stage air pump works by means of a piston that moves up and down (could also be side to side) inside a cylinder. It admits air into the compression chamber at the top of the stroke and forces it out the exhaust valve or port as the piston moves down. The larger the diameter of the piston, the more air is inside the compression chamber to be compressed. The longer the piston stroke, the more volume inside the compression chamber, as well. So those two things determine the amount of air that gets compressed — the diameter of the piston/compression chamber and the length of the piston stroke.

As the air is compressed, its pressure rises. This is felt as resistance on the pump handle. The higher the compression, the greater the resistance. Small diameter piston = lower compression/resistance. Larger diameter piston = greater compression/resistance. Therefore you can compress more air with a large-diameter pump piston, but the resistance will build up faster. And a smaller-diameter pump piston lets you compress air to higher pressure, though less air is compressed with each stroke.

The question is, to what pressure do you want to compress the air and the answer is another question — how much do you weigh? Because when you reach your weight, it isn’t easy to pump any more.

But wait — there’s more!

Hold on, B.B. You said that the length of the pump stroke also determines how much air gets compressed. Couldn’t the pump have a very small piston with a really long pump stroke, and therefore compress a lot of air to a high pressure? Why, yes it could! Mr. Conners would be proud of you.

So — how tall are you? You see, when the pump stroke gets longer than you can conveniently pump, all the fancy science stuff doesn’t matter. A hand pump with a 5-foot (1.5-meter) pump stroke isn’t very useful, is it? Not only is it hard to carry, it’s also difficult to operate when the pump handle comes up over your head on the up stroke! You need that handle to be low enough that you can lean on it on the down stroke. It really matters when the air pressure/resistance rises beyond a certain point. That point is determined by your height and weight.

Mechanical advantage is possible, and some vintage pumps use it, but they’re rare compared to the bulk of the pumps we know about. The single-stage manual pump I have described today is the most common design encountered in vintage airgun equipment.

Dennis saw where I wanted to go with this experiment, and he took up the challenge enthusiastically. He used two different vintage-type pumps of his own manufacture, plus the modern Axsor pump to check efficiency. He also made a 9 cubic-inch air reservoir with a built-in pressure gauge.

test fixture
The test fixture Quackenbush made to ascertain pump efficiency. The pump that’s attached to the test reservoir in this photo is the smaller one with the 5/8″ piston head. The reservoir holds 9 cubic inches (about 147.5 cc) of air. Wit this setup the operator stands on the pump handle (left) and pumps the air reservoir up and down (right).

antique hand pump
This is an antique hand pump. The reservoir — a ball in this case — is screwed onto the top of the pump between the handles (left). The operator stands on the pump base (right) and pumps up and down several hundred times to fill the ball.

Summary

That’s where I will leave it for today. In the next installment I’ll tell you the results of our testing, and also why the three-stage hand pump is so good.

Don’t forget that this work was done to discover the potential power of antique big bores. We are concentrating on the hand pumps, but that was just part of what we were exploring.

147 thoughts on “Hand pumps for the ancient big bores: Part 1

  1. Thank you BB . This is fascinating stuff for me and the ability that 18th century engineers and craftsmen were able to create these pumps is amazing. I still need some math to fully understand it all. I weigh 180 lbs. If I made a single stage pump with a one square inch diameter piston and used my full weight would the maximum pressure be
    180 PSI ? Thank you again.
    Harvey


  2. G’day K7,
    You are forgetting the mechanical advantage of a small diameter chamber. Sure you can only put 180lb on the pump but I would guess with the right mechanical advantage it may well be 3-5 times your weight 180 x 3 to 5 PSI.
    But that calculation for a 1 square inch sounds like it could be right but how long is the chamber, maybe if the chamber only took one cubic inch of gas it could be right…I think maybe Boyles Law comes into this calculation some where with heat generated.
    OK BB, don’t be a B, you have us dangling on the hook! How high can you go in PSI with a one stage pump?
    Cheers Bob


  3. More good stuff,BB ,thanks! I’m curious how they would have been able to charge to a consistent pressure each time. I don’t see any kind of pressure gauge in pictures that I’ve come across of the ball reservoir guns. If a different size “Bubba” had pump duty this time, would it be the same pressure as the 50lb. lighter “Shorty” was able to attain? And would it really matter if wasn’t pretty close to the same? Accuracy?
    Oops, I think I might have sort of answered my own question. The POI with my Discovery only moves 2 clicks on scope ( at 15 yds. Less than 1/8 “) between shots#1 and #20 and that’s not until #18. So different fill levels would not matter too much, right?
    I stop my shot count at 20 because I’m running out of air at that point. Gonna try to fix that a little with a power adjuster and a hammer denounce install. Hope it will help.




      • BB
        OK, now I understand about valve staying open longer, but I don’t see the connection with velocity changes. Using JSB 18.13 gr. ( it really likes this pellet) it shoots a high of 810 fps and ,after #18 it drops to 798 fps. I think that is a really good balance as gun is tuned now, but when I use a lighter pellet, 14.35 gr, the velocity drop over 20 shots is much more pronounced, 160 fps from first to last shot. Why?
        Bruce



          • BB
            So my thought of a debounce device is inline with better use of available air. I don’t need 26 fpe to take a squirrel or pidgeon so I can give up 35 to 50 fps to get an extra 5 or 7 shots at 23 or 24 fpe. Is that possible if I install a power adjuster with it?


            • Bruce,

              I wouldn’t know the answer without testing, but your numbers seem a little too optimistic. You might get one or two more shots that way, but I don;’t know about 5 to 7.

              Drop the energy to 16 foot pounds and 5 to 7 more shots would be a lot more probable.

              B.B.


              • Thanks BB,
                If it’s possible to adjust down to 650 fps. , at 17 fpe , paper would be afraid and rabbit would still be DRT!
                It’s snowing here in Denver and am stuck inside and don’t like it! Thanks, BB and have a great weekend!
                Bruce


            • BBs about right if the marauder is any indication of how the discovery would act with a power adjustment, to go from the mid 20s to 30s was ten shots and a much heavier pellet, so with the same pellet it might not lose almost any ft lbs to get 5-7 shots, but the disco gets less shots to start, it might take a lot more then we think. The wasted air with the lighter 14.3s seems twofold, the valve open longer with pellet using it less, and the loss of resistance so quick dropping the valve closed and bouncing like BB said, also. The debounce is supposed to do good things for consistency and ahot count, definitely a desired mod. I personally think shot count for squirrels is good over 5, rock chucks or sparrows or starlings, need more, but if your gun gets 5 shots deadnuts at an energy range thats effective then to me thats a fine squirrel gun.


              • RDNA,
                One good trait of the Discovery is its ability to maintain consistent shot placement even at lowerd velocities. The 18.13 gr. JSB’s maintain an average of 805 fps for over 15 shots on 1900 psi. fill. That’s about 25 fpe.That’s alot of energy for squirrels! I know the Disco is not a Maurder but a few simple mods should make a decent gun perform even better!
                Bruce


                • Oh yeah, the disco is a great gun, for its price and ease of use, getting 25lbs and even 15 shots is a lot when you consider that guns like the mrod pistol, escape and even some large reservoir EXPENSIVE pcps get 15-20 shots, sometimes much less. I have the disco on my very short list of next hopefuls in 22, in order of price it goes mrod 22 convert parts, disco, hatsan AT-44 10W. In order of desire, hatsan, disco, rod parts. I am thinking ill end up with the hatsan if im continuing to be patient, rodder parts if I cant, and disco if its somewhere in between, lol.



                  • BB,
                    Thanks for the tip on Disco Double link! A lot of stuff for me to digest on one read thru but I’m up for it! First step will be the HDD and power adjuster and test that combo. Will keep posted with results.
                    Thanks,BB!
                    Bruce


  4. BB,

    My question concerns the intake valve for the hand pump. The engineer in me has been grinding on how they solved that issue back then since we brought these up the other day. What arrangements have you seen?


  5. RR,

    There is no intake “valve”. Think 2-stroke engine. The piston uncovers the intake air inlet hole near the top of its stroke, air rushes in and when the piston goes back down, the inlet is sealed. It’s simple and it works.

    B.B.



      • RR
        Just looked at it. Pyramyd Air doesn’t give much of description about it.

        I’m wondering if you think its like a UTG Bug buster scope. To me I’m thinking it is much longer.

        Not a FWB 300 compatible scope.


        • BB,

          No, not very much at all. They do not even state the type of reticle. I am certain it is longer than the Bug Buster, but with the large objective lens and the side focus it might become competitive with the UTG SWAT line, most especially if it can withstand a magnum sproinger. I have two compact SWAT scopes right now and I am in the market for another scope. I am considering a Bug Buster, but I really like side focus.


          • RR
            Your reply got sent to my email. Did you mean me or BB?

            Anyway once I went to the sidewinder scopes and used them I will never go back to the front adjust scopes.

            I shoot with both eyes open and I use the small knob. That way I can take a glance at it to check my range without even taking my shooting eye away from the scope or off the target.

            Hmm maybe I have ambedexterous eye sight. 🙂


            • GF1,

              I thought I was responding to BB’s comment, but it was you who replied to me. My bad.

              I too am addicted to the side focus, that is why I wanted to know more about that Optima scope. I should probably just stick with UTG and dream about a Hawke. Like I said, I have two right now and every UTG scope I have looked at I have been impressed with the quality versus the cost.

              So are you saying the Bug Buster is not getting much use? Maybe it needs a new home? 😉


              • RR
                The Bug Buster scope has been back on the first 300 I got from you for several months now.

                Sorry but its staying on the 300. That is the 300 that still has all the stock factory parts in it. In other words not modded. That Bug Buster scope works real nice on it.

                Wish I had a extra scope but I don’t right now. You should look into one of those UTG 4×32 fixed power scopes. I believe if I’m remembering right they are set at 50 yards on the parallax. That should be good focus from about 15 yards out to 60 yards. And they have a very bright and sharp sight picture.

                I had one and Reb has one. Maybe he will see this and tell about his. But I liked the one I had. And they are just $50 if I remember right. Maybe that would work for you.


                • GF1,

                  I ended up robbing Peter to pay Paul and have a UTG 4-12×44 Compact SWAT on the 46E and the Edge now, so I am good to play for a while as soon as the weather and the clock let me. I still need another scope, but there is not “rush” right now.


                • Yes, it is a nice scope and the price is right. I believe it was $54 and it’s front focus.
                  I’ve shot it @ 8 yds and out to about 60.
                  It has a sharp image anytime I use it but it was too big for my QB-88 so I’m still in need of a BugBuster for it but have the 4×32 mounted on my 2400 and they work well together.



  6. Love these blogs B.B!

    Interesting to think about how things were developed years ago – my favorite series was “Connections” by James Burke.

    I recently found a link to a 240 year old mechanical doll which is an impressive example of engineering – even by today’s standards. I am attaching the description and link below for those who are fascinated by this kind of stuff…

    Happy Friday!!

    Hank

    Watch the doll’s eyes as he writes w/pen on the paper. A 240-year-old doll that can write, a clockwork creation by Pierre Jaquet-Droz. Yes, it is 240 years old. This video will fascinate just about all the engineers, artists, clock
    makers, doll makers, computer programmers, want-to-be inventors or basically anyone out there that likes to tinker. This is more than tinkering. When you view this, think computers. Enjoy. It is truly amazing.
    Remember, this was built in the 1770’s.

    http://www.chonday.com/Videos/the-writer-automaton


  7. BB,
    I have read that the military Girandoni rifle reservoirs were filled with pumps attached to the wheels of horse drawn carts or wagons. That might have allowed higher pressures than when hand pumped.

    David Enoch




      • BB,

        I have no clue really, as I have seen no examples or illustrations, but I picture a rig not much different than the early fire pumps. You could have two pumps, one on each side of the fulcrum, perhaps both feeding into a manifold that would allow you to fill multiple reservoirs at one time. With the mechanical advantage of long levers you could have a relatively large piston and long stroke, thus allowing for the “rapid” refilling of multiple reservoirs.




  8. Mr. Gaylord:
    Mr. Gaylord:
    Thanks for bringing out the STEM aspects of air gun hand pumps. You should considered doing a video segment for Pyramyd’s Airgun Academy explaining the science technology engineering and math behind of hand pumps. I encourage juniors in the crew to watch Airgun Academy segments to familiarize themselves with some of the basics of the sport. And this subject would make a good addition to the Academy collection.
    William Schooley
    Rifle & Pistol Coach
    Crew 357
    Chelsea, MI


  9. I have to ask this about the pumps.

    I wonder if they were able to achieve higher pressure by laying the pump on the floor with the base against a wall. Then sit on the floor with your back against a wall. Like maybe a hallway. Then use your legs to push on the handle to pump the gun. You could use your hands to pull the handle back towards you. It would be kind of like rowing a boat.

    Your legs have way more power than your arms and body weight. What do you think? Could the pioneer pcp gunners of used this method to achieve higher pressure.



      • BB
        Got to be better than using just your arms and body weight.

        Oh and in my younger days a 150 setups and leg presses was a piece of cake. Its a little tougher now. But still can do it. Just will take me longer. I’m 54 years old and still lift weights and exercise in my basement.


      • BB
        Whoops didn’t catch the 300 leg presses first.

        Really it took 300 strokes to fill one of the early pcp guns even to only 600 psi? I know that was a lot of psi back then.

        I guess they could have multiple people taking turns to pump the guns up if out in the feild.



          • BB
            Very true. That’s what makes me think that it was just hard work they had to do if they wanted to survive.

            Things were tuffer back then. Farming, industrial and even at home. So maybe they didn’t think it was any thing out of the ordinary for them to do filling those early pcp’s.

            A different time and culture back then.


          • BB,

            You also will notice that all of the antique airguns had removable reservoirs. They could have their servants fill two or three the night before “the hunt”.

            Also, as you noted in previous blogs about these airguns, they would get quite a few shots from one fill. The Giradoni was supposed to get about forty shots on one fill. Very likely they would only need one or two shots on a hunting excursion.





            • I was just gonna say, boy am I thankful to have the best all around modern pump made as of yet, the G6. I have no experience with others, but from BBs great review, my own experience with its ease of use and steadiness, at the price I have to assume you can’t get much more by spending more.


              • The G6 does sound pretty good. I have a Hill and an old AirForce. The Hill is so much better, there is no real comparison. I have to wonder how the G6 compares to the Hill. I have to say that I like the looks of the foot plate on the G6. I have been thinking of making a new foot plate for my Hill. I am not too impressed with it.



                • The first thing I did was screw the foot plates down to a 1/2″ piece of rectangular pine, little bigger then the whole floor section, not that it wasnt sturdy, but I have large feet, and I want it standing up right at all times, only use in the house so dont need to transport it in current times, and want it sitting squarely on the shelf I store it at all times. If I ever need to bring it anywhere its two screws on either side and its back to original.


      • B.B.

        Unlike Gunfun1, I’m a 55 year old couch potato. Lifting a 50 lb bag of top soil just about does me in provided my lower back doesn’t go out. Unless I can transform into The Incredible Hulk, there’s no way I could handle several hundred pump cycles on one of these hand pumps. Are any of the newer hand pumps easier?



        • Cstoehr,

          Don’t feel bad. I can relate. Very near on age, and maybe not quite a full blown “tater”,…yet…..after a full 40+ hr. hand’s on week,….it’s “tater” time for me too! 😉 Chris


          • Chris and Charles.
            I work most of the time over 48 hours a week. Run up and down cat walks all night and back and forth across the shop which is easily 200 yards long and a 100 wide. I lift equipment all night long. And turning wrenches among other things.

            My body aches all the time now compared to when I was younger anyway.

            But here is the big thing. If I stop lifting the weights at home and exercising I feel even worse. It’s like I can’t even move.

            The worst thing to do is be inactive. Try to make yourself do the exercises and such and you will feel better.

            You know I was going to mention a resolution I made for new years but didn’t for multiple reasons. But here it is. Try to not spend so much time on the internet and not watch as much tv. Not that I watch much tv right now but try to stay away from it more.

            If you keep active and try to do just some exercising you will feel better. Then work yourself up to some weight lifting. Not nesicerily for muscles but for stamina. And it will help make you a better shot if you stay with it.

            What’s that saying. “Nothing good comes easy”.



              • BB
                With you 100%. And yes the range of motion.

                I do sit-ups, bends and strechs, jumping jacks, push ups and pull ups.

                And it helps that I got two teenage daughters that push me to keep going. They do all the yoga things also.

                It really does make a difference.


          • Don’t be so hard on yourselves. I don’t work at all anymore and spend more time on the couch than anywhere else.
            I have two forms of strenuous activity that I can do on a fairly regular basis; my bicycle and my handpump, I can stop pumping anytime I want for whatever reason but it’s not so easy on the bike, always gotta get back home!


  10. Oh and about the update on the $100 pcp in a couple weeks.

    Isn’t that around the Shot show time? Does that mean their will be a $100 pcp released for sale?

    Just putting two and two together. You don’t have to say if you don’t want. But I do hope its true. Maybe we can get more people converted to the dark side.




      • B.B.,

        I wonder just how big of a ruckus a $100 pcp will cause in the industry. The Discovery caused one, and the Marauder did, too. But this could be an even bigger spark.

        That and a sub-$1000, single-unit, multistage 4500 psi compressor would be even better than a good five cent cigar!

        Michael


        • Michael
          Oh it will be big. Especially if it comes from a reputable gun maker like Crosman than made the Discovery.

          Only if the marketing gets done right.

          Hey BB any idea who launched the Discovery pcp. 😉


        • Tell me about it!
          I just learned I have a hiatal hernia and I’m sure as soon as I tell them I’m using a hand pump to compress air to 2000psi they’re gonna shake that finger and I’m just getting started!


          • Reb,

            Using a hand pump should not be an issue. My wife has a severe hiatal hernia, and I have a small one. There really aren’t too many physical activity restrictions that I know of. Eat slowly, avoid foods such as rice or toast, which go down the esophagus very slowly, avoid eating large quantities in one sitting, be sure to drink liquids as you eat, take an antacid such as Prevacid or Nexium once in the morning and once at midday, and try to sleep with your head, chest, and shoulders a bit elevated.

            I know that’s a long list, but if you do all of the above, a hiatal hernia is usually no big deal.

            Michael


            • They just told me it showed up on the X-ray so far, it’ll be another month before we talk about it but I’m trying to learn as much as I can before our discussion so Thanks for the info!



      • Reb
        Flying Dragon has had one for along time. I got one back when BB was doing the reports on the $100 pcp.

        They were a $100 at the time I got mine. I believe the gen 2 is around a $150 now. I got one of the last of the gen1 $100 pcp’s he had.


        • Yes, but the last time I checked, they’re offering their new and improved version at a slight increase although it looks like money well spent.
          Doesn’t the $150 model come with a repeating breech?




              • Reb
                I do believe at one time he offered a repeating mechanism you attached to the gun. I thought about getting it then just decided to stay with single pellet loading.

                Heck I got a single shot tray in my Marauder. And that was something I was going to say the other day when someone mentioned putting pellets in their pocket when out shooting. Someone mentioned the pellet skirts getting bent. Then the other person said they shot into sand and recovered the pellet and the skirt was flared open and not bent anymore.

                Well that made me think. And another reason to go to .25 caliber. Those pellets are so beefy especially the skirt thickness. It would be pretty hard to bend the skirts on them. So fill up the pocket with some .25 caliber pellets and head for the woods and single pellet load them.

                With no worry of bent pellets.



                  • Reb
                    The point I was trying to make is the .25 caliber pellet is a more I’ll say durable pellet as far as handling goes.

                    Put some .22 or .177 caliber pellets in your pocket and walk in the woods for a couple hours. They won’t be in as good as shape as the .25 caliber pellets.

                    But I will say I got one of those Crosman pellet pouches that attach to your belt. It does seem to be better than putting them in your pocket.


                    • I actually used to use the plastic box that Daisy sold their wadcutters in! That’s also where I got my first pellet seating tool.




  11. For reasons I cannot remember (although I started only an hour ago), I began searching for information regarding the assault on Daisy (oh,yeah, B.B. mentioned Dennis Quackenbush and I visited his site and stumbled on some thing he wrote).
    Here is the link to that page:
    http://www.quackenbushairguns.com/Airgun_articles.html

    First the Consumer Products Safety Commission (CPSC) and when they lost clout as the original members were replaced, the American Society of Testing and Materials (ASTC). I know that B.B. was involved along with Robert Beeman and others to provide professional, objective information and evidence to counter the CPSC and ASTC claims. Even the NRA got involved, among others.

    I say all of this as a prelude to the next link. I stumbled on to a Field and Stream article I read when it was fresh on the news stand. It is not primarily about the suit against DAISY although there is mention of petitions to the CPSC in 1975 that sought to severely limit or ban air guns in the U.S.

    Bob Brister learned about air gunning after an accident left him to flinch while shooting any firearm, even a lowly .22. The article begins on page 118 and the Feinwerkbau 300-S figures prominently. He covers the development of the modern air gun and touches on social and legal issues as well.

    Mr. Quackenbush speaks of incrementalism in his writing. Some (who spend no time here) don’t understand why the NRA is so adamant about protecting the Second Amendment. As it is, the camel may already have his nose in the tent. The NRA leadership and members all know this.

    ~ken


  12. Interesting article. My first thought as a “do-it-yourselfer” is how can I make one? How can I make a compressor that will make 3000 psi? My Grandpa made a compressor from 2 cycle engine and an old washing machine motor. Belt driven and mounted on a 2X8 board. Grandpa is gone, but Dad still uses it to fill an air tank to 120 psi. At some point a high pressure air compressor will have to work much harder and could stall an electric motor. Then the heat? Then the condensation? Cooling?

    Any thoughts or links to such matters would be of most interest.



      • GF1,

        Spent about an hour looking things over. Videos were loading slow, so not sure what is up there. At any rate, refrigerator compressors seemed to be an option, but was unable to find what psi they would pump air to. Maybe a more pointed question would be, ” can a person make a homemade 2000-3000 psi automated compressor? “. I will research more.

        Today will be shopping and then trying out different types of tape on the front of targets to see if I can get super clean bb punches. I got the spare TX200 trigger guard and will be installing a trigger stop screw after checking out a few more specifics. Going with a 4-40 thread through .085” non-magnetic metal.


        • All I can think about homemade high pressure compressors… you guessed it, DANGER, DANGER Will Robinson. Lol. I watched some refrigerator compressor builds and if a person has hvac or commercial cooler experience, but most wont. All I picture is is that a car tire with 50psi can blow you off your shoes! Just giving that obligatory disclaimer.


          • RDNA22,

            😉 , Thanks. Still, I do not give up easy. I would like to know what an fridge compressor can do though,…as a start. It could be that there is no “other” thing that can be used as high pressure compressor. I take things slow and do research as I go. Done right, a lot of “impossible” things can be done. I was just thinking that maybe I could build one for around 250. Less than a Shoebox and a whole lot less than an Omega.


            • Chris USA
              Search “Lloyd Sikes hydraulic combined high pressure testing”.

              He is who made the double tube kits for the Discovery. He use hydraulics with high pressure air to test his tubes he makes. I believe he tests to 6000 psi. He has some cool video’s on You Tube.

              And like RDNA said. Danger
              Got to know what your doing. My brother is a electrical engineer plus has his own heating and air conditioning biusness. He told me a little about the refrigerant compressors. The big danger is the head pressure and heat it creates. And will keep building and evently blow up.

              As RDNA says. Danger
              And kids don’t try this at home unless you have somebody there with you that thoroughly understands the system.


              • 😉 Thank you. I am getting the feeling that this is a no-go deal. I would imagine that you did explore the possibilities as well? I will check out the link. Video did fine on Vana2’s “doll” link above as opposed to earlier when it would barely function.


            • The highest pressure I’ve heard of from a reefer compressor was 900psi and the guy dumped the compressor oil and refilled it with silicone oil first
              He was just using it as a blow gun.
              I checked em out myself a couple years ago.
              Just get a pump!



            • GF1,

              As with most things for public “consumption”,….they tend to be over built for the idiots out there. Think of lifting straps, man lifts, scaffolding, etc. I think man safety is 3-5x under rated. Ex: 200 lb. limit is actually 600-1000 lbs.

              Still, no doubt you have a point. Know what you are doing,…or leave it alone.


            • You know it, I have sense enough to just plug in the pump, shoot the pellets, pump it back up and repeat! I have a degas tool but there’s no reason to go under the skin of the marauder, everything’s right there. Switching out the barrel and bolt shouldn’t require degassing but im one to read every thing and watch every video about something before doing it, even if that’s a paver patio I hadnt done much of, didnt know the best base layer thicknesses etc so read 3 books, 12 articles and and 5 videos at least before laying the most awesome patio me, the homeowner or the boss had ever seen! Right now my obsession is axes, for some reason, they are awesome tools. I had all that cherry and a birch we fell (using 550 paracord to keep it away from the house cause the guy supposed to bring rope is a dim bulb/no, not me!/) but dont underestimate quality paracord… anyway, off and on different things I do start taking over every once in awhile.



                • It goes to 2000 without a hiccup, 5-6 pumps maybe, 10 at the most, then you start pushing your weight a little and for 5 more pumps you get a little bit more air, to about 2100-2200. Then your in the mud at 75-80% weight/work till 2500-2600, about 15 pumps. From there to 3000 is 100% weight getting on it and to hold it down. Probably 15-20 last pumps. The number of pumps are estimates but the effort and time ratios to the different psi levels tell it best anyway. Total time is something like 7-8 minutes from 2000 to 3000, I go a slow and steady pace pausing at top and bottom but taking a much shorter pause and a faster stroke it can be cut in half, like 4-5 minutes tops.


                • Going to 2000 psi is basically just filling the hose because my bottom pressure in the reservoir isnt under 2000, so thats something to think about when using lower pressure guns, a gun working at 1500 to 2500 will not be work to fill at all.



                    • If you get a pump you’ll be able to see where your at with the pump gauge. You might be able to get a good idea of the start pressure by the feeling if when its actually starting to open the reservoir, like how I said its super easy then you feel it get going, thats when you hit the guns pressure and actually start working it in. How are you filling it now? How do you know the 500 end?


                  • My intention is to only run it down to 1000psi and I’m usually pretty close at around 8-900, but I have no magazine to help keep track of shotcount or reservoir pressure gauge for reference and power goes down pretty quick below 1000.
                    The Benjamin pump I got from GunFun is the only means I’ve had since switching from Co2 and it seems to be doing well enough for me.
                    But so far the highest I’ve been was the 2500psi test charge on the one I got for the 2400kt.



                • I am and im not, I love the marauder, love it in 17, love it in a shoe, in a house, with a mouse, in a box with a fox… but what I don’t like right now has been having no time to shoot! Its just started snowing so it’ll be slow for the next couple months, so it will take a couple weeks probably and I’ll be back on to trying to set up shooting time constantly, but this last couple weeks I’ve been feeling sluggish. I’m really seasonally defined, bursts of energy and lead in my bones rotates about every three months.


                  • RDNA
                    That’s called getting old.

                    And we haven’t got snow yet. They have predicted it here and there put keeps missing us. But it has been down in the single digits at night and teens during the day for a few days now. I don’t care for that cold weather anymore. I’m ready for spring for sure.


                    • I think your right, but even through younger years I’ve been a hard swingin pendulum. Down is down, up is up sorta deal. Its funny seeing my kids, the youngest is 3.25 yrs and still hates clothes, they want to go outside no matter what, and even when the house is cold if were conserving oil the kid won’t keep clothes on! Im like whats wrong with you!? Im putting my army outers on and runnin wild and free, lol. But I remember a clear line between shorts in the winter and “Aww, heck no!, gettin another jacket!”



                  • RDNA
                    I have always been a hot blooded person. I use to wear just a flannel shirt if it was 20 degrees out. No coat. I always could stay out in the cold hunting longer than my buddies when we was kids.

                    Always out doing something weather it was burning up hot or freezing cold. 54 years old now and the bones just don’t like the cold no more.

                    Matter of fact have thought about moving south to Texas or something in about 3 more years when the youngest daughter graduate’s high school.

                    Just have to see how it goes.


                    • I know what you mean, Texas has lots of attraction for us hot blooded Americans, the weather, the mindset toward freedoms. Around here you can Live Free or Die in New Hampshire, but your not getting any warmer, nit by a long shot! Beautiful country though.



          • GF1,

            Will do. Ended up with a 6-32 set screw. No 4-40 set screws at the local hardware. Should work fine. I got a 3/8, 1/2 and 5/8 with a nylon insert jam nut and a nylon washer. Should work just fine and will not have to remember to follow through on trigger pull. Should be real nice. The guard was only about 18$ through PA. I may do the LGU, but it is plastic. Metal ones? Still, minimal stress, so plastic would work as well I imagine. Most likely will do tomorrow AM.


  13. B.B., (others welcome)

    I just received a Lyman trigger gauge. Very nice and very easy to use. One question,….as with a springer, that can not be dry fired, how do you check the trigger? Once the trigger breaks, the rifle will jump forward, thus adding to the actual pull weight. (I am assuming here) How do you get around this, or this not a problem?

    Just thought I would ask before I started playing with it. Thanks,…..Chris



      • B.B.,

        Thank you. I will try as you said, which is pretty much what the instructions say. I just thought that the initial opposite recoil of springer airguns might be a factor to consider.


      • B.B.,

        By the way, I got your book and read the 1st two stories early this AM. It was all I could do not to just burn right through the entire book. Instead, I will savor it as a fine cheese, a craft brew or a fine spirit. I got a feeling it will be over all to quickly. For fiction, you like to throw in a “twist” at the ending,.. thus far…..

        For the rest of you wondering, this is a fine 6×9 paper back w/145 pages. I do believe P.A. left that out.

        Very good,…. and that is only 2 stories into it. Skip that extra 250 tin of pellets and get the book.

        Chris


      • B.B.,

        Worked good. The TX broke at around 13oz. and the LGU at 1# 15oz. Got more variance that I cared for.

        The LGU was shooting better this summer, so I may have to bump up the TX some. At least I got something to measure adjustments by. That is nice! 🙂

        By the way, I did the TX trigger stop. Real nice. Got a spare guard from P.A. to play with. 1/16″ past the break. Still need to shoot it more, but for now, I like it real well.


  14. OFF TOPIC! What has happen to the Crosman MAR177 (ar-15) UPPER PCP Conversion Kit?? Finally got a lower and can’t find (mar177 kit) it any where? No listing? Have the recent current events caused this kit be taken off the market? Help! Semper fi!


  15. Didn’t get much airgunning done today but I did stick one of my JSB Monsters in my buddy’s 1″ plywood lifesize human target with my 7 .5″ barreled 2240 on HPA.
    🙂


  16. Question,

    Scope rings, Weaver mount………I went to a Weaver mount on the LGU and tried a set of UTG rings that had the round cross pin. The pin tried to “ride over” the Weaver slot. Buldawg recommended Wally World and the Weaver brand Weaver mounts that have a {square} cross pin. Quad-lock if not mistaken. Solid and works great. At any rate, the Weaver brand options are somewhat limited on 30mm. scope tubes.

    So here is the question,…..on Weaver style mounts, is the square cross pin a (Weaver brand) exclusive, or, do (other brand) Weaver mounts also offer a square cross pin? Most pics on sites do not show the underside of the mount.

    Any help appreciated,….Chris


    • Chris USA
      Really the pin tryed to ride over. I would think if you got the side clamps tight that would not happen.

      I have had the round pin ones on quite a few guns and never had that problem.

      Had them on a Diana 54 air king which is probably the worst gun for that. No problem. Also on both FWB 300’s, the 46e and even the Bengamin Nitro Piston guns I had. No problem like that all.

      Something sounds strange there. What kind of adapter or riser did you go to. That’s on the LGU right?


      • GF1,

        The UTG drooper DN T06. It was not severe and the clamps were tight, quick release I believe that could also be adjusted for clamp pressure. It makes no sense to me that they would make a round pin to go into a square slot. I like the square pin and would like to stay with it. The main thing I was wondering if anyone else has seen square pins on anything other than the Weaver (brand) mounts.

        I will take into account your experience from your comment. I think I have some med. round pin UTG in 30mm., so you may have saved me some coin if so. Yes, that was on the LGU. I tried a Hawke adjustable drooper mount that stripped one of the 4 screws. That’s when BD recommended the T06 and the Wally Weaver brand rings.

        The new mount is for the TX and just wanted something that I could get some of the UP out and optically center the scope and keep it close. It worked real well for the LGU.


        • Chris USA
          Why I asked about the adapter is. If for some reason they didn’t make the square cut out up high enough so it would be up above the pin. Or as long as the top of the notch was higher than the pin that should never happen.

          Look to see where the top of the round pin is in relation to the top of the adapter notch. If its only contacting half of the side of the pin diameter then it could be a problem.



            • Chris USA
              I think your talking about the pin diameter of the scope ring.

              I’m saying the notch in the adapter must be over the top of the pin when you mount the ring on the adapter. If its not. Yes the radius of the pin could try to ride up out of the notch.

              What I’m saying is when you put any brand ring on the adapter that has the round pin no matter what diameter it is. You need to make sure the sidewall of the notch in the adapter is higher than the top of the ring cross pin.

              Just because a scope ring maker or adapter maker has products available doesn’t mean they hold tolerances that will work with all combinations of rings and adapters that are out there.

              You have to test fit to see if each product will work with one or the other.

              Wouldn’t it be nice if someone could put a list together of what ones or compatible together. You know how that goes.


              • GF1,

                For sure. Ring height too. Weaver mediums are 25mm. and UTG mediums are 32. I did have a set of UTG med., but I think I need to go low, at least with UTG. Since no one seems to know if there are any other brand of square pin Weaver type rings out there, I will go with a set of Weaver brand, lows. Time to look around.

                For PCP’s, I am sure the shallower pin grip would not be an issue. Springers need all the scope/mount grip they can get though.

                Thanks, Chris



              • GF1,

                It is not the rail height, that looks fine. It is the lack of pin depth that I think is the issue. I am guessing that only a third the UTG pin diameter is exposed, when just over 1/2 would be ok for a round pin style Weaver.


                • Chris USA
                  Whatever way the pin has to be in the notch. If half of the pin is exposed above that .118″ dimension than I would say that could cause a problem.

                  What I was thinking and like what you mean. The pin in the ring is almost above that .118″ dimension. Or the .118″ dimension is shorter than .118″.

                  So that needs looked at first. Maybe mount one ring on the rail and see if the pin fits down in the notch far enough before putting the other ring on and mounting the scope.

                  But if it was me. I would eliminate the Weaver/picatinny adapter and just find the right ring for the dovetail on your gun. If you use the stop pin on the back ring in the hole in the dove tail the ring should never move. They make all kind of different ring heights so you shouldn’t need the adapter. Just one less variable in the scope mounting if you ask me.


  17. Picked up a pet in my hallway the other day; striped bark scorpion, went out and dug up a grub for him earlier but I think he’s scared of it, they’re definitely keeping their distance.


  18. GF, B.B., Thank you for your reply’s! Went out to FB and others! Got a reply from a FFL Gunsmith familiar with the MAR177 upper and best for lowers! Gunsmith claims there problems with the MAR177? And a Good one I guess? Claims they were being tuned up over 850 fps? No control over use of the MAR177? It may all be hearsay? Just don’t know if I will continue to pursue this choice of air rifle? As a Veteran I feel we are all under attack for our personal sports, when it has anything to do with any type of guns, make, powerplant, rimfire, centerfire etc.! Thank you all for your contributions to the sports! Semper FI!!


  19. So how powerful were antique big bores?

    I read that they were used by the military in some countries so they must have been powerful enough to kill a human easily enough to be useful in a war….

    Air gun technology hasn’t really progressed much at all if you think about it.


    • Zebra,

      Welcome to the blog.

      I did write a report in the history section on this very topic. Click on the link at the top of the page to see all those reports, or just click on this link.

      /blog/2015/08/how-powerful-were-the-big-bore-airguns-of-the-past/

      I scanned that report and see that I didn’t fully answer the title question, so this coming Monday I will address it just for you.

      B.B.


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