Home Blog  
Ammo S&W Model 29 .44 Magnum BB revolver: Part 3

S&W Model 29 .44 Magnum BB revolver: Part 3

SW 29
S&W model 29 BB revolver from Umarex.

Part 1
Part 2

This report covers:

  • The test
  • Charging
  • Hornady Black Diamond
  • Double action
  • Loaded the cartridges in the cylinder
  • Daisy Match Grade Precision Ground Shot
  • Air Venturi Dust Devils Mark II
  • H&N Excite Smart Shot
  • Now for pellets
  • RWS Hobbys
  • Hobbys on a fresh CO2 cartridge
  • Trigger pull
  • Discussion
  • Summary

Today we look at the velocity of the Smith and Wesson Model 29 BB revolver from Umarex. And today I really did get the velocities.

The test

I tested the revolver in both single action and double action with steel BBs, lead BBs, frangible BBs and with lead pellets. Since the cylinder holds 6 rounds that was the test — the average velocity of 6 shots. I tried to allow at least 10 seconds between shots but as the test advanced I saw that this revolver doesn’t lose as much velocity as it goes.

You saw the chewed up cardboard box on Wednesday, but I’ll show a picture to remind you.

To register the BBs I had to aim at the same place on the box every time.


I installed a fresh CO2 cartridge in the pistol and turned the piercing screw with the wrench on the inside of the left grip panel. Naturally I put a drop of Crosman Pellgunoil on the tip of the cartridge before installing it. No gas escaped when the cartridge was pierced so I had to shoot the gun to know if it was pierced.

Hornady Black Diamond

The first steel BB tested was the Hornady Black Diamond.  In the single action mode six shots averaged 428 f.p.s., with a spread from 423 to 434 f.p.s. That’s an 11 f.p.s. difference. 

In the double action mode six BBs averaged 426 f.p.s., with a low of 418 and a high of 438. That’s a difference of 20 f.p.s.

Double action

The trigger advances the cylinder quickly in double action and then it stalls. It’s a relatively light pull after that, but if you go easy you can hold it at this point every time. 

I had to hold the revolver with two hands to get the BBs to register on the chronograph. The window for the skyscreen to “see” the BB is very narrow.

Loaded the cartridges in the cylinder

Since a reader asked if it was possible, I tried loading with the cartridges still in the cylinder and found it to be very convenient. This is how I loaded for the entire test.

M29 BBs loaded
To load swing the cylinder out and drop each BB into a cartridge, then press in with your thumb.

Shop Outdoor Gear

Daisy Match Grade Precision Ground Shot

The next and last conventional steel BB I tested was the Daisy Match Grade Precision Ground Shot. In single action six of them averaged 412 f.p.s. The low was 407 and the high was 419 f.p.s. for a difference of 12 f.p.s.

In double action this BB gave a real difference, with an average of 437 f.p.s. The low was 427 and the high was 453 f.p.s. — a difference of 26 f.p.s.

Air Venturi Dust Devils Mark II

Next I tried Air Venturi Mark II Dust Devils. They fit the BB cartridges very loose and I felt they would be slower because of it. As loose as these BBs fit I don’t think they will be accurate.

In single action six BBs averaged 401 f.p.s. the low was 372 and the high was 417 f.p.s. That’s a difference of 45 f.p.s.

In double action six Dust Devils averaged 415 f.p.s. The low was 409 and the high was 429 — a difference of 20 f.p.s.

H&N Excite Smart Shot

Next to be tested were six lead H&N Excite Smart Shot BBs. They weigh over two grains more than conventional steel BBs, so I expected them to be slower, which they were. In the single action mode six averaged 346 f.p.s.with a low of 333 and a high of 363. That’s a difference of 30 f.p.s.

In the double action mode Smart Shot averaged 352 f.p.s. The low was 338 and the high was 361 f.p.s. — a difference of 23 f.p.s.

Now for pellets

The M29 is a smoothbore BB gun, not a pellet gun. But several readers asked me to try pellets, so I did. I used RWS Hobbys to test it.

RWS Hobbys

The RWS Hobby pellet averaged 345 f.p.s. in single action and 319 in double action. But on the double action test I noticed that the velocity started dropping after the third shot, which was the 64th shot on the CO2 cartridge. So I exhausted the gas and installed a fresh CO2 cartridge. There were perhaps 10 more shots that sounded good, though they were more than 100 f.p.s. slower than the average with the same projectile. Call it 12 cylinders (72 shots) per cartridge?

Hobbys on a fresh CO2 cartridge

On a fresh cartridge Hobbys averaged 395 f.p.s. in the single action mode. The low was 373 and the high was 417 f.p.s., a difference of 44 f.p.s. The pistol was using liquid CO2 for the first couple shots, and I think the average was influenced by that. You can tell when liquid CO2 is passing through the valve because there will be a big white puff of condensation after the shot. The liquid CO2 is flashing to gas inside the barrel. Those shots are always faster because there is more pressure behind them.

In double action the Hobby pellet averaged 394 f.p.s. and the spread went from 373 to 413 f.p.s. — a difference of 40 f.p.s.

Trigger pull

In the single action mode the trigger breaks at 6 lbs. 13 oz. In double action it breaks at 9 lbs. 8.5 oz. It’s heavy for single action and very light for double action. I can feel some movement but no creep (jerky movement) in the single action mode.


The M29 shoots a little faster in the double action mode most of the time. I don’t think it’s worth doing that because some of the accuracy will be lost, due to the movement of the gun.

I would definitely recommend loading the cartridges while they are in the cylinder. It’s so much easier because the cylinder holds them so well.


Well, the accuracy test is next. I’m thinking of doing the BBs separate from the pellets, so each type of ammo gets a good trial. Stay tuned for the results!

102 thoughts on “S&W Model 29 .44 Magnum BB revolver: Part 3”

  1. “I tried loading with the cartridges still in the cylinder and found it to be very convenient.”
    That’s really cool. I think that’s a big factor for a “fun gun” like this, where people will most likely want to do a lot of fast shooting…that’s how I would want to use it! 🙂
    Looking forward to the accuracy reports,

  2. BB,

    Thanks for checking velocities SA and DA. I was surprised at how close they were, with the DA actually running higher in some cases. My DA groups are a little lower on the target than my SA groups, leading me to believe their velocity was slightly lower. Must be some other reason.

    Shooting mine SA is a real trial–not much fun at all. DA, however, isn’t bad. I start the DA pull fast, which clicks the cylinder into place, and then carefully press through the rest of the very smooth pull until it lets go. I’ll probably be shooting this gun DA most of the time from now on.

    • Snake 45, I was shooting a spring piston air rifle the other day and I was testing pellets. I assumed the Baracuda .22 pellets, which are 21-something grains would be slower and hit lower on the target than the Baracuda 15s and 18s that I also tried. Not so. The heavier pellet grouped almost an inch higher at 10 yards! Sometimes there is an interaction between the gun and the pellet that is counter-intuitive. In my case, I think the heavier pellet takes longer to get out of the barrel and so is affected more by the significant recoil of my Beeman R9. In a CO2 gun, there isn’t much recoil, but there is some, and a faster pellet may hit lower because it gets out of the barrel faster before the recoil, however slight, can move the barrel. Just some food for thought.

      Next big investment for me is a chrony. Santa, are you reading this blog?

      • RG,

        A chrony is a must, but do not get too hung up on it. It is great when you are learning a new airgun or you are tuning a sproinger or PCP, but dragging one out every time you shoot? Nah. I have one. Most of the time I do not use it, unless I have a lady moving into RRHFWA. Then I will use it some to see how she is feeling.

        I would recommend the Caldwell chrony. If you shop around you can find a real good deal on one. Also, they have an app for that.

  3. B.B. I was shooting an old but new to me Crosman Mark II yesterday, which I was able to reseal by myself using the wonderful tutorial filed as a guest blog by 45Bravo. The best pellet so far for this gun was JSB S100 heavyweight wadcutter which are 8.26 grains. And since I just received two tins of JSB Simply Pellets, I noticed that coincidentally, one of the Simply pellet tins was labeled 8.26 grains. I wondered if I could adjust the power of the hammer spring to get the most accuracy out of the Simply pellet and if that would translate into even better accuracy out of the S100s, which are sorted at the factory. The gun came to me with the power screw turned down to the max, of course. So I cranked the power adjustment screw all the way out and started shooting 5 shot groups of the Simply Pellets. As I turned the power adjustment screw in a quarter turn each time, the groups started getting smaller until I got to a point where the 8.26 gr. Simply pellets recorded a two-hole group about .25 inches apart, center to center. Not bad for cheap pellets. So I had high hopes for the S100s, thinking they would be even more consistent. Perhaps there would only be one small hole rather than two. To my surprise, the S100s were scattered all over the place. Well, that shoots that theory!

    Next time, I’ll start with the S100s and see what power level they like best, and I’ll shoot 10 shot groups. Then I’ll see if the Simply Pellets like that power level too.

    I may also try to clean the barrel with JB … who knows what’s in there … and then season the barrel with 20 or so pellets. At least I will know I am starting with a blank slate.

    Any other thoughts or insights are welcome.

    I am quite pleased with these Mark Is and IIs. I am very happy that you recommended them to me. And 45Bravo has been a wonderful guide and very generous with his time and advice. I have my fifth Mark I or II on its way to me. I think what I will do is keep a few on hand for when family or friends want to try their hand at pistol shooting or give them away to any aspiring young marksmen or markswomen I come across who show a sincere interest in the shooting sports. They are fun to fix up and fun to shoot!

    • RG,

      I have quite an extensive collection of pellets in .177 and .22. I always try to find “the best” pellet for each of the gals here. Once I do that, I get a Wilkins Pellet Pouch to hang with it (if it is one of the wall hangers) filled with “the pellet”. Sometimes you will be surprised by what works best.

      • You are so right. I was testing the latest addition to my Mark I / II collection, a non-adjustable Mark II and everything I tried was shooting wild groups way to the left. However, HN Match Green, a light 5.25 gr. wadcutter made the best group. But I am at the limit of the rear sight rightward adjustment and I am still shooting to the left. Can the barrel on a Mark II be bent? OR is my first step to take everything apart and clean the barrel first?

  4. B.B.,

    Ah the velocities of a non-blowback air gun!

    Last night my wife and I watched a Korean TV series in which a federal agent snapped the cylinder of a revolver shut. I cringed. Apparently some bad habits transcend borders. :^(


  5. Today, being a revolver day, I took courage for an off topic question for help after all these years here with you guys.
    After replacing the broken main spring of an 1858 Uberti the hammer doesn’t fall after pulling the trigger, although the cocking procedure seems to be o.k.. I can only push the hammer down by pushing it, using force.
    Any help is highly appreciated since there are no gunsmith around the territory.

    • Bill,

      You just removed the old hammer spring and installed the new without much disassembly?
      When you installed the new spring did you do it with the hammer down? Did the HEAD of the spring where the notch is go under the “ball” of the trigger at that notch or indentation on the hammer spring easily?

      Can’t figure out why you need to push the hammer forward unless something else is broken and blocking the fall of the trigger.


  6. Just a quick heads up, folks.

    P.A. has some refurbished R7s, R9s, and HW 50S that were not there a week ago, and they won’t last.

    I got a refurbished R9 a few months ago and it was like new.

  7. When the pellet is heavier, it will strike higher, not lower, untill it flies past the midpoint of its trajectory.
    The arc of the slower projectile is greater than the faster one. I will check on chairgun.

    • 1stblue,

      “The arc of the slower projectile is greater than the faster one.”
      I will agree with you.
      From the bore line out the slower projectile appears to drop faster than the lighter one but as you pointed out that isn’t what is actually happening. Here on Earth within the limits of Newtonian Laws Gravity doesn’t care what you weigh (or your MASS is) you will fall to Earth at about 9.8m/s/s.
      But Roamin Greco didn’t see that outcome! He could be right that the heavy pellet spent longer in the barrel and that recoil changed the bore angle up…but it could just as likely have been harmonics that changed the angle. Without Chronograph data we have little to go on. The heavier pellet might even have had a higher MV!
      Roamin Greco is learning well: “Next big investment for me is a chrony. Santa, are you reading this blog?” I hope he has been a “good boy” and gets his wish from Santa!


  8. What I’m wondering is what would be easier on the revolver when loading after all the bad talk of snapping the cylinder open or closed.

    I wonder what uses less pressure. Inserting the pellet or bb into the cartridge and loading the cartridge.

    Or leave the cartridge in the gun and load the pellet or bb into the cartridge.

    After enough loading with the cylinder hanging open would have to put some wear and tear on the cylinder arm if your not supporting the cylinder some way.

    • Gunfun1,

      I wonder if a firearm .44 caliber speed loader would work with this air pistols cartridge cases?

      The crane itself is fairly strong. I think the problem is in the peening of the cylinder rod (axel that the cylinder rotates on) or spring loaded pin at the rear of the cylinder and/or the hole in the frame that captures it on closing. The only thing that really makes sense to me is some peening in the cylinder center shaft or the cylinder axel itself. I find it difficult to believe that the frame or crane itself is getting bent…but then what do I know how hard folks snap the cylinder open…just can’t bring myself to even try to do that once!

      Would it make a difference if you used a speed loader? I use a speed loader on my firearm revolver most of the time. When reload I hold the cylinder with a few of my off hand fingers; speed loader or individual cartridge automatically…just checked.


      • I thought of using a firearm speedloader and getting some extra sets of fake cartridges. But first I checked the diameter of the rims. The diameter is smaller than the rim of the real .44 Spec/Mag case, so wouldn’t work in a M29 speedloader. It’s also smaller than the rim of a .41 Mag so almost certainly won’t work in that one either.

        You’re not going to do this crane any damage by pushing the BBs into the fake cartridges, trust me.

        • Snake45,

          Thanks for that information on the rim size; that is a big negative for me.
          I was beginning to lean toward getting one of the airgun M29’s to do timer drills with at home but now i will wait until the rest of B.B.s report is done.


  9. 1stBlue, I enjoy a good ballistics discussion, but you can’t use Chairgun, or any other trajectory calculator, to answer this one.
    Why? Because they are all recalculating the trajectory of the bullet based on the new variable, (The weight, or velocity, or for some, the angle), based on the information you key in. And that isn’t what we want to do here.

    So, assuming that Roamin Greco’s observations are verifiable, and GunFun “might” be correct, try this little thought experiment:
    Imagine a 10 grain pellet exiting a fixed barrel in a perfectly horizontal position, and draw that trajectory in your mind. Scribble the curve on a piece of paper if it helps. (it drops continuously down, never rising above the horizontal line of the barrel)
    Now launch a 15 grain pellet from the same, fixed, horizontal barrel. Imagine a new trajectory for this pellet. Important point here: The weight of the pellet, which INCREASES the rise of the trajectory on Chairgun, is not the factor. All things fall at the same speed, so the only thing to think about is the speed. In this case, the 15 grain pellet is travelling much slower than the 10 grain.

    Draw that curve right on top of the one you drew for the 10 grain.
    Can this slower projectile ever exceed the bounds of the first curve you drew, or does it always need to stay below the first curve?

    So how can everybody that knows from experience that the heavier pellet hits higher be right, when the laws of physics say this is wrong?

    Jane Hansen….

    • Jane, you are 100% right about physics. If we ignore air resistance, two objects fall at the same rate, and gravity accelerates that rate of falling over time. However, the reason the heavier pellet can hit higher is because of what I alluded to in my comment, above, about some things acting on the pellet that may be counterintuitive. When we begin to factor in air resistance, forward velocity, recoil, a 12 pound double action trigger with loads of travel, and a thousand other factors, strange things start to happen, right? And we are assuming the heavier pellet travels slower, but what it the skirt of the heavier pellet gets a better seal than the lighter pellet? (Although I generally would agree with you). My point is we are making assumptions, but many factors combine to give an observed result.

      So what can we really predict? I will just take a couple of Tylenol to reduce the effects of these thought experiments on my tired brain and go shoot a lot of pellets.

      Here’s one for the weekend: I shot my spring piston rifle one day from a bench rest with the back of my hand resting on a sandbag, gun on my open palm just in front of the trigger guard. From what I have learned reading this blog, this is classic artillery hold. I shoot with a peep sight at ten yards. All my shots on that day (10 targets, 10 shots each) go into satisfyingly small holes in the black at about 7 o’clock from the center of the bullseye. Next day, I go back again, and do everything exactly the same, and I get the same result, except all the groups are at 12 o’clock and just outside the black! Somebody please cure me of this affliction! The squirrels are laughing at me.

      • Roamin Greco,

        “I go back again, and do everything exactly the same, and I get the same result, except all the groups are at 12 o’clock and just outside the black! Somebody please cure me of this affliction! The squirrels are laughing at me.”. The squirrels laugh at all of us most of the time!

        You claim to do everything exactly the same…not even close!
        Until you are a World Class shooter, or put in that level of work the Force will NOT be with you!

        A bummer but do the best you can and make certain it remains FUN!


        • Well, I may never be a world class shooter, but I am determined to improve. Maybe even to the point where I can feel somewhat confident that I can hit what I am shooting at and not let it be chef’s choice everyday.

          I like the Star Wars references, too. I am but the learner, you are the master. I’m re-watching Rebels with my kids.

          • Ran out of room to reply directly. I have been and always shall be, a trekkie who loves Star Wars! Loved Next Generation. Loved the original series. Loved all the movies.

            I saw a Smithsonian exhibit in DC years ago about the mythology of StarWars. Super cool. I the first 3 movies, but funny story–saw Empire first and it was also the first movie I had ever seen that did not have a happy ending. I was really crushed! And I was crushed again when Han finally bought it in Episode 7. Didn’t care for the last two movies, but enjoyed the ride.

            Never got into Babylon 5. Might look into it…when I’m not shooting ;o)

    • Jane Hansen,

      “So how can everybody that knows from experience that the heavier pellet hits higher be right, when the laws of physics say this is wrong?”

      If you shoot straight up at Zenith or straight down at the center of Earths Mass the “experienced” shooters WILL be wrong!
      But Roamin Greco doesn’t have a Chronograph(s) or a Lab RADAR so he has no idea of MV or down range retained energy.
      As you said, falling is only one (constant — almost) factor in a many factor ballistic equation’s solution.


      • Shootski, I knew I could count on you to keep me humble. But I am still enjoying the discussion, and trying to remember high school physics. Just wait a couple of years and I’ll have my daughter’s textbooks to study (again).

        Jane I hope nothing I said offended.

        Have a great weekend everyone. Just keep shooting!

        • RG,

          Babylon 5 is full of terrible acting. If you can get past that, some of it is pretty cool.

          I used to have a problem with my Gamo CFX. At 25 yards I could put ten pellets in a group that could be covered by a dime.

          I started having an issue with my group moving over to a different spot. Same size, just different location. Eventually I figured out it was how I placed my trigger hand thumb. I was able to shoot in one group and then the other just by repositioning my thumb.

          It does not take much.

          • You are right, of course. Sometimes it can be maddenning if you are not aware of subtle differences in your technique. It is enough to drive some people to the dark side!

    • Jane
      Probably what is missed here with everybody’s guessing is with the sight in of the gun with the light pellet then shoot the heavy pellet at the same distance with the sight in of the light pellet.

      So all of a sudden this heavy pellet does strike high.

      How and the heck could that happen. Oh my.

    • Jane, forgive me. Who am I to tell you you are right about physics when you are an applied physicist. All I have is a hazy recollection of high school honors physics. I enjoyed your comments on this blog, and I look forward to learning more.

  10. Roamin,
    You are, of course, correct. My thought experiment was to point out that, all things being equal, heavier, (hence slower), projectiles cannot hit higher than lighter / faster ones.

    For sure:
    A gun sighted with heavy pellets will hit higher than a gun sighted with lighter pellets, in the early parts of its trajectory – we elevated the barrel when we zeroed in the heavy pellet.

    A heavy pellet may obturate better than a lighter one, and possibly exit the muzzle faster – possible, maybe, but highly unlikely. They are all design to seat in the barrel, and for lower powered devices, sometimes the gain from the better seal is offset by the increase in friction.

    Recoil – more likely. There is no thing as a “recoiless” rifle. The laws of physics are immutable. As soon as the pellet begins its forward motion, there is a force being applied in the opposite direction somewhere. Because we hold almost every gun with its barrel slightly elevated, that force can induce a rotation, and slightly exaggerate that elevation. A heavier pellet will result in a greater effect.

    If we were talking firearms, then barrel whip, resonance, spin, earth rotation, etc., would also start to factor in more.
    I like air rifles because I don’t need to think about those things.

  11. All,

    I do enjoy reading the comment/discussion in these blogs. It feels much like my experience as a very young person, sitting in my Grandfather’s parlor listening to my father, uncles and Grandfather talk huntin’ and dogs. Good stuff…


    • Yep, I agree. But my Dad and Uncle never mentioned the gravitational constant when they were trying to figure out why they kept missing. :o)

      Being the budding gun-nut of the family, I took a lesson out of an old Jim Carmichael article from Outdoor Life magazine and was able to determine that Dad flinched badly by slipping in an empty case during pre-deer season sighting-in, and cured that by suggesting he trade in his Remington .30-06 pump rifle with the see-through scope mounts (an abomonation). He got a bolt action .270 and can’t miss. My Uncle’s issues with his Marlin .30-30 were solved when I put Dad’s old scope on it so he could aim better and told him to leave the variable power on 3 and to stop shooting at the antlers. He never missed a doe, but he had buck fever, bad. He’s better now.

  12. This is off topic but I didn’t know if you would see this if I posted on old report. Yesterday the mail brought me a Joseph Lurch gallery gun in .29 cal. It has it’s original crank. It is not a twin of the one you have made by brother David but is very close. One look though and you would say it is a Lurch. It fires. Got it off E-bay for half what I thought it was worth!

  13. Ok you all one of my most favorite sayings is Chairgun is just a estimator.

    How about we all stop talking about what we think will happen and let’s shoot and see what happens.

    And remember try multiple different scenarios. Like different sight in distances with a scope then with different magnifications with the different weight pellets. Then try with open sights. Then a dot sight Then a peep sight.

    Physics is fun to think about. But shooting and seeing what happens is more exciting to me.

    Which do you think will tell the truth. Physics or the paper. As in the target. I done this roundy round with building engine’s and race cars. The equations tell one thing. But the car going down the race track tells everything.

      • RidgeRunner,

        “The main problem with theoretical physics is accounting for all of the possible variables. Most of the time that is pretty nigh on impossible.”

        I account for all of them that I know of…then it turns into a REALLY BAD case of cat herding when you try to shoot ;^)
        Ran out of REPLY above on your .357 Speed Loader post. The cartridges have wiggle room so as long as there are six holes it might work if the diameter of the case fits the loader and the rim is retained.
        Maybe Tom or a reader owns a few speed loaders he/they can try.
        I’m surprised that PA or the manufacturer hasn’t done that “homework” for another accessory to $ell!


    • FM
      No where to reply to you above.

      I remember Flash Gordon when I was a kid.

      Didn’t they fly the rocket around suspended from a string with a smoke trail rising out the back of the rocket. And that was a black and white show wasn’t it from what I remember. Or maybe it was color and we still had a black and white tv. ???

      • They were black-and-white movie theater serials; there were 3 of them made:
        “Space Soldiers” in 1936, “Trip To Mars” 1938 and “Flash Gordon Saves The Universe” in 1940. FM did not like the last one that much. ‘Lil FM watched them on black-and-white TV. You’re right about the rocket ships; believe if you can find one of those original models you will be left with a lot of space in your wallet. 😉

        • FM
          I remember them from in the mid 60’s when Gunfun1 was a young’n. They was fun to watch. And I remember thinking to myself why and the heck is the smoke rising and not blasting out the back of the rocket.

          Hmm I think Gunfun1 would like to watch one now days and see what the movies are like watching them after being a tad bit older now. 🙂

  14. Gunfun1, You make me laugh…”who do think will tell the truth, the physics or the paper”..
    The physics always tells the truth. The some people go out and start shooting, (or drag racing), and observe a whole bunch of human-induced variables, and then conclude that they know something.
    The trick is to find out why your observations don’t agree with the physics, and try to identify and remove these variables from your experience. If you can do that, you will have a very predictable model of how your gun, (or car), will behave and you can become more proficient at whatever it is you are trying to to.
    In my trade we work very hard to develop models that account for as many “environmentally” induced variables as possible, so that our real-world events unfold as we want them to.
    To do otherwise would be catastrophic.
    I guess it’s all your definition of fun.



    • Jane
      Useless work. We always laughed at the people that stacked horsepower ratings for a add on. When they was done they thought they was going to have a 750 horse power engine and found out real quick there are more variables that show thier face.

      Put it on the dyno and see what happens. That’s real world. Then go run the car and see what happens. All of of sudden more eyes open and jaws drop when they found all that money they spent was useless.

      Yep good ole physics.

  15. Jane Hansen,

    I am almost certain you have heard this thought on modeling usage by British Statistician George E.P. Box:
    “All models are wrong, but some are useful.”
    Folks have tried in various ways to lessen the sting of his 1976 voiced view. The quote, however, lives on with every “improvement” in the practice of modeling.


  16. B.B. Nice blog on Friday. I think you had 2 comments by 9 am, but it was cool how the conversation blossomed to include physics lessons, the word “obturate,” Star Wars vs. Star Trek, motorcycles, and chronographs, among other things. I love this blog. See you Monday.

  17. Surely Gunfun doesn’t suggest my endeavors, (and occupation), is ” useless work”, and of course I take no offense.
    I don’t know a whole bunch about cars, but I suspect that the folks that were “stacking horsepower ratings” were not true physicists, and weren’t the tools that applied physicists, (we’re not theoretical physicists), use to predict the outcome of such things. More likely they were using second-grade math.

    The applied physicists that actually calculate engine output are quite good. Rocket engine output is calculated with quite a lot of details, including all of the external variables that are required for advanced ballistics, and the little buggers tend to go exactly where we predicted they will. (most of the time, at least).

    But even cars can be fairly well modelled. Surely you were all around when Bob Lutz, (former VP of GM), told the world that Cadillac was going to build the worlds’ fastest production sedan. (2008) The team that designed that car was actually advertising the horsepower of the engine, (556hp), before it was even SAE tested. They turned out to be quite correct. (SAE certified even higher).
    And they were also good enough with calculating the effects of a completely new suspension, body, and drive-train geometries that they only needed to send ONE car to the Nubergring in Germany, and were able to claim the title with that very car in very short order. Nothing in the car save a few suspension tweaks needed to be redone. The car pretty much ran exactly as predicted.
    But then, they were true scientists…

    • Jane
      That’s exactly what I mean. There were people that raced and biult cars that worked and they then sold aftermarket products to the public. Those racers found out by trying the different things that they put down on paper.

      So then as you call it the second graders would buy these parts and put them on thier engine and expect this cam and this intake then that carb and so on would give a determined horse power with them all combined. And which is by no way true.

      Then there would be the people that would ask how is your car running so fast. You would tell them in detail and they would put thier cars together with the same components and not run as fast.

      Why? Variables. What I would call physics is like Chairgun. It’s a estimator and it’s real world when you put it to action.

      And yes I messed with Chairgun quite a bit. It will get you in the ball park but it is not real world. Real world is when you try out what Chairgun says and see what really happens.

  18. Jane, of course there is a place for physicists, engineers, architects and others who rely on science to predict the outcome of a build. One cannot build a skyscraper or an airplane engine by trial and error. But of course to GunFun1’s point, those folks benefit from the empirical experience of those who built things before them. So there is a place for models and a place for experience. To GunFun1’s credit, if I recall correctly, he demonstrated that sometimes, a pellet can have a spiraling trajectory. So I think there is certainly value in both perspectives.

    But I think the second grade math comment was unnecessary. I mean you don’t really know them. They may have been using new math. ;o)

    • Roamin Greco,

      I got to drive my Viggen (Born from Jets) on the Nürburgring what a Blast! Actually, the SAAB aeronautical engineers used the turbos from their reciprocating aircraft engines in the SAAB turbo cars they initially built to fill down time from aircraft work.
      My second grade Math class was what they call pre Algebra these days. You can never tell what folks did in second or third grade math in the old days just by todays standards of dumbing down everything to make sure NO Child is LEFT behind….


    • RG
      And of course at some point in time something is put on paper and formulas applied. But it’s another thing to apply those formulas and see what really happens.

      Belive me I have used a lot of different formulas building race cars. And we didn’t know the truth till we took it down the track.

Leave a Comment

Buy With Confidence

  • Free Shipping

    Get FREE shipping on qualifying orders! Any order $150+ with a shipping address in the contiguous US will receive the option for free ground shipping on items sold & shipped by Pyramyd AIR during checkout. Certain restrictions apply.

    Free shipping may not be combined with a coupon unless stated otherwise.

    View Shipping Info

  • Shipping Time Frame

    We work hard to get all orders placed by 12 pm EST out the door within 24 hours on weekdays because we know how excited you are to receive your order. Weekends and holiday shipping times will vary.

    During busy holidays, we step our efforts to ship all orders as fast as possible, but you may experience an additional 1-2 day delay before your order ships. This may also happen if you change your order during processing.

    View Shipping Times

  • Shipping Restrictions

    It's important to know that due to state and local laws, there are certain restrictions for various products. It's up to you to research and comply with the laws in your state, county, and city. If you live in a state or city where air guns are treated as firearms you may be able to take advantage of our FFL special program.

    U.S. federal law requires that all airsoft guns are sold with a 1/4-inch blaze orange muzzle or an orange flash hider to avoid the guns being mistaken for firearms.

    View Shipping Restrictions

  • Expert Service and Repair

    We have a team of expert technicians and a complete repair shop that are able to service a large variety of brands/models of airguns. Additionally, we are a factory-authorized repair/warranty station for popular brands such as Air Arms, Air Venturi, Crosman, Diana, Seneca, and Weihrauch airguns.

    Our experts also offer exclusive 10-for-$10 Test and 20-for-$20 Service, which evaluates your air gun prior to leaving our warehouse. You'll be able to add these services as you place your order.

    View Service Info

  • Warranty Info

    Shop and purchase with confidence knowing that all of our air guns (except airsoft) are protected by a minimum 1-year manufacturer's warranty from the date of purchase unless otherwise noted on the product page.

    A warranty is provided by each manufacturer to ensure that your product is free of defect in both materials and workmanship.

    View Warranty Details

  • Exchanges / Refunds

    Didn't get what you wanted or have a problem? We understand that sometimes things aren't right and our team is serious about resolving these issues quickly. We can often help you fix small to medium issues over the phone or email.

    If you need to return an item please read our return policy.

    Learn About Returns

Get FREE shipping on qualifying orders! Any order $150+ with a shipping address in the contiguous US will receive the option for free ground shipping on items sold & shipped by Pyramyd AIR during checkout. Certain restrictions apply.

Free shipping may not be combined with a coupon unless stated otherwise.

View Shipping Info

Text JOIN to 91256 and get $10 OFF Your Next $50+ Order!

* By providing your number above, you agree to receive recurring autodialed marketing text msgs (e.g. cart reminders) to the mobile number used at opt-in from Pyramyd AIR on 91256. Reply with birthday MM/DD/YYYY to verify legal age of 18+ in order to receive texts. Consent is not a condition of purchase. Msg frequency may vary. Msg & data rates may apply. Reply HELP for help and STOP to cancel. See Terms and Conditions & Privacy Policy.