Claims of Gas Operated Being Less Powerful than Pump or Recoil Operated

Since gas is bled off to operate the action, the velocity will be less than in the pump gun if all else is equal.
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Have you proven that with tests over a chronograph?

I have tested my reloads over a chrono through both my gas gun and my O/U - velocities were the same - all running between 1208 and 1219 fps
 
I suspect that by the time the shot charge reaches the gas port, the shot has already gained at least 95% of its ultimate muzzle velocity, maybe even 99%, especially with target ammo.
Shotshells use fast burning powder like pistols do, in fact many shotgun powders double as pistol powders. I chronographed some .38 special loads in both a 6 inch revolver and a 24 inch rifle, the additional 18 inches of barrel on that rifle only added about 100-150 fps to the bullet, and that includes the advantage of not having a cylinder gap to bleed off pressure.
 
Chrono data

At this point, the question has been definitively answered twice....there are two references to chrono data (posts 5 and 22) which show that there is no difference in velocity from one type of action to another.

I get the impression that people don't read all the posts.

Imagine I quickly punch your shoulder with 25 ft lbs of force. Then I place my fist in your shoulder and gradually increase pressure until I reach 25 ft lbs. It is the exact same force, but one is more comfortable than the other.
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Yes, that is true. The analogy is inapt, however, since the difference in application of force vis a vis the recoil of one type of firearm to another is nearly impossible to detect....microseconds.
Pete
 
The analogy is inapt, however, since the difference in application of force vis a vis the recoil of one type of firearm to another is nearly impossible to detect....microseconds.
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Au contraire, it is quite easy to feel the difference. My buddy and I could even detect the difference in feel due to a lengthened forcing cone with 94% accuracy - well past coincidence. Notice I did not say less, I said different. We had no way to accurately measure the difference.
 
The same thing has been reported with gas operated rifles, but repeated tests over chronographs show that the difference in velocity due to the gas operation is less than the normal variation in a box of shells or cartridges.

Not something to lay awake nights worrying about.

Jim
 
Test

Quote:
The analogy is inapt, however, since the difference in application of force vis a vis the recoil of one type of firearm to another is nearly impossible to detect....microseconds.
Au contraire, it is quite easy to feel the difference. My buddy and I could even detect the difference in feel due to a lengthened forcing cone with 94% accuracy - well past coincidence. Notice I did not say less, I said different. We had no way to accurately measure the difference.
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Virginian: if you were able to that in a blind test, then must defer to your experience.
Pete
 
I believe that if a lengthened forcing cone, back bored barrel, or slow burning powder changed the recoil of a shotgun, it most likely also changed the muzzle velocity.

Here are some sure fire ways to reduce recoil:
Reduce the muzzle velocity
Reduce the weight of the shot
Make the gun heavier
 
Here are some sure fire ways to reduce ACTUAL recoil:
Reduce the muzzle velocity
Reduce the weight of the shot
Make the gun heavier
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Fixed that for ya.....;)

I did that for my gas gun - 3/4oz, 1210 fps, added 6oz to the mag cap. Breaks targets, doesn't break the shoulder......:D
 
Re: Velocity between O/U and auto

FITSAC, All things have to be equal. You used 2 different guns. Lock the action on the auto and test it against it in semi auto mode. 10 shots in each mode. Let us know.
 
I'm not brave enough to shoot trap with 3/4 ounce loads, but low velocity one ounce loads absolutely smoke the targets if I center the bird in the pattern and are reasonably pleasant to shoot out of a 8.3 pound BT-99 trap gun.
The more I study the shot ballistics charts on pages 104-105 in my Lyman Shotshell Reloading Handbook, 5th edition, the more sense it makes to keep the muzzle velocities subsonic. The difference between the 40 yard velocity of 7 1/2 shot with a mv of 1330 and 1135 fps is only 65 fps (715 vs 650 fps), and at 60 yards, the difference is only 40 fps, (580 vs 540 fps).

OK, maybe the extra mv makes the lead less tricky, so I compared time of flights between these two velocities to go 40 yards, .129 vs .145 seconds. A difference of .016 seconds or enough time for a clay bird traveling 40 mph to travel 11 additional inches.
That may be the main reason that international trap loads shoot their 24 grams of shot at such high velocities, it's certainly not because a 1145 fps load wont break the birds.
As for me, I think I can learn to shoot 8.5 ft in front of a 40 yard bird instead of only 7.5 ft.
This of course assumes that the bird is still going 40 mph after it's 40 yards away, which it most likely is not.
 
Lock the action on the auto
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:confused: ya lost me - these were fired one shot at a time from two different guns on the same day - the results were the same. I was just glad to see such a low SD and nice consistent velocities.
 
The difference in energy on target between a pump and a semi all else equal is the same. Chokes and centering the pattern on the target is a big part of these ignorant assumptions that a pump delivers more energy on target.

We use a pattern board in class and in many cases, same load and choke, we see different pattern sizes. A 6" steel plate at 25 yards with a C choke usually won't get knocked off the stand. If I put in a full choke, I can flip it 10 feet.
 
How does one lock the action on a autoloader?

Maybe you put a bolt through the receiver behind the bolt, that would lock it in place.
Not on my Browning!
 
How does one lock the action on a autoloader?
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Put a solid rod in place of the spring on an inertia gun, use a shim to seal the gas ports in the barrel hanger of a gas gun. Do not attempt to actually "lock" the action as it can result in damage.
 
Put a solid rod in place of the spring on an inertia gun, use a shim to seal the gas ports in the barrel hanger of a gas gun. Do not attempt to actually "lock" the action as it can result in damage.
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What would be the point? A chronograph will tell you whether the speed is the same. If the ammo and gun weight are the same, then the recoil is the same.
 
There is little point germaine to the topic at hand.

However, there are other reasons one might not want an autoloader to cycle.
 
Put a solid rod in place of the spring on an inertia gun, use a shim to seal the gas ports in the barrel hanger of a gas gun. Do not attempt to actually "lock" the action as it can result in damage.
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It would certainly make the recoil feel different to the shooter. Even the last shot when the slide locks open feels different from the other shots.
I can tell when my .22 semi-auto pistol shot its last round because of how different the recoil feels when the slide locks open.
 
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