Why shorter BBL have more recoil?

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DefiantDad

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Why does a shorter barrel have more felt recoil? Shouldn't the bullet exiting the barrel sooner leave less gas pressure? It seems counterintuitive. Bullets should have velocity increase, to a point, with longer barrels, so it is accelerating for a longer time within the barrel.

Or is it the WEIGHT of the barrel that is the reason behind more felt recoil, from less mass and thus less inertia?
 
A short barreled revolver has less mass(weight) and a long barreled revolver tends to soak up the recoil to a point. My 686 Smith has a 6" barrel and it smacks hard. My 44Mag Ruger single action has a 7.5" barrel that pushes on ignition. Heavy bench rest rifles hardly recoil at all with small caliber bullets.YMMV
 
Simple inertia.

The longer barrel weighs more and soaks up more energy, and it takes longer for the recoil to lever it up or back against the hand.

rc
 
PabloJ said:
Extra blast makes recoil impulse seem more severe than it is.
Click to expand...

This, (plus the blast is closer to the shooter) less weight at the end of the gun and the usual smaller grip combine to increase/seemingly increase the kick.

Muzzle blast is often confused with actual recoil impulse. The .357 magnum WW white box 110 JHP has tremendous muzzle blast, but not a lot of kick. It took a few rounds to realize the bark did not match the bite. Yet observers are impressed by how well you can control those "hard kicking full house magnums"
 
As was already mentioned, inertia, and some other laws of physics. "For every action there is an equal and opposite reaction." If there is an explosion that pushes a bullet out one end of the gun, there is going to be force going back into the shooter. The more gun you have to absorb that force, the less felt recoil. A longer barrel means more mass, from the barrel and from the gun surrounding that longer barrel. On a side note, a heavier gun will have less felt recoil. Take for example to pistols: Sig 229 and Sig SP2022. They are almost exactly the same size and shape, but the 229 has an allow frame and is heavier than the polymer framed Sp2022. I have shot both extensively, and you feel the difference. In this day of smaller and lighter handguns with stronger more powerful +P ammo, there is still some wisdom in a full size metal gun, be it 1911, sig P series, or even (eek) a revolver! Hope this helps answer your question.
 
(1) Less weight
(2) The angle between the muzzle and your gripping hand is more acute, generating more flip.

I imagine the recoil king would be a Super Redhawk Alaskan in .454.
 
I don't believe shorter barrels actually have any more recoil. Recoil with any gun is largely between the ears and there are many factors that can trick our brains. Recoil that comes straight back is less objectionable than from a gun that has a lot of flip. A louder gun is more objectionable than a quieter gun. Smaller grips concentrate the recoil into a smaller area of your hand. Shorter barrels with smaller grips are more objectionable to shoot, but I don't believe the recoil is any different.

Feel free to plug in the numbers, but you first must get exact chronograph readings and weights from two identical guns with different length barrels. I'm betting the recoil difference is neglible, but wouldn't be surprised to find that the shorter barrel actually has slightly less recoil.

http://www.handloads.com/calc/recoil.asp

Recoil is a factor of 4 things, the guns weight, the weight of the projectile, the weight of the powder charge and the velocity of the projectile. With rifles going from a 24" to a 22" barrel produces a small weight reduction and a small velocity loss which should balance out. Going from a 6" to a 4" revolver is about the same weight loss, but the velocity loss is significant.
 
I believe the percentage of weight lost from a 6" to 4" revolver is significantly more than a 24" to 22" rifle.
 
It's mostly weight.
Aside from that, I'm going to say that it is, in part, because less barrel means less energy absorbed inside propelling the bullet. In turn, that means that the left-over powder is making a 'rocket' effect at the muzzle.
Probably a very small part compared to the forward weight, but something to think about.
 
Remember also that handgun recoil is as much rotational (e.g. muzzle rise) as it is linear, and shortening the barrel reduces the moment of rotational inertia much more than it reduces the overall mass of the gun, hence much more muzzle flip with the shorter barrel.
 
^ +1

Yes - with a long enough lever you can move the world.

It's not just mass, it's where its at. If I could magically move all the mass to the end of the barrel there would be less muzzle flip than if I magically moved all the mass into the lower back part of the grip.
 
It's Short Handgun Syndrome. The shorter handgun feels less adequate. It hits you harder to make up for it.
 
the thing to it is proportionate weight. a 32 oz gun shooting a 158gr bullet is running a gun to bullet weight ratio of 88:1, by cutting off a few ounces of barrel weight that drops to 80:1, or ten percent more recoil just by removing a few inches. Plus, theyre at the front, where weight really helps keep the muzzle down, and even thou the gas is not compressed nearly as much, your still propelling the unburned powder and gas, which contributes to recoil.
 
I don't believe shorter barrels actually have any more recoil. Recoil with any gun is largely between the ears and there are many factors that can trick our brains.
Click to expand...

Simple math equations prove this to be false - ACTUAL recoil is a simple math equation where the weight of the gun IS a factor and a shorter barrel WILL have less weight.

PERCEIVED recoil is how it feels to YOU as an individual and depends on grips, technique, etc. and will be different for each individual
 
mjsdwash said:
the thing to it is proportionate weight. a 32 oz gun shooting a 158gr bullet is running a gun to bullet weight ratio of 88:1, by cutting off a few ounces of barrel weight that drops to 80:1, or ten percent more recoil just by removing a few inches. Plus, theyre at the front, where weight really helps keep the muzzle down, and even thou the gas is not compressed nearly as much, your still propelling the unburned powder and gas, which contributes to recoil.
Click to expand...
If you factor in the reduced velocity of the bullet from the shorter barrel, that ten percent will be reduced. I don't know if it could be reduced enough to get into the negative area, but some, certainly.

Taking the weight off the front of the gun does reduce its moment of inertia (rotational inertia) super-proportionally, so the muzzle rise effect may be reduced more that 10%.

Then there is a bit of rocket boost of the escaping gasses and unburned powder you mention. This force may actually be increased.

Lost Sheep
 
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the reduced velocity will be offset somewhat by the reduced weight of the gun.

agree on the increased velocity of the powder gases. less volume in barrel means more gas pressure, hence more velocity. don't think the mass of the gas is enough to make a big difference, although, the increased velocity can't be good for your hearing.

the moment arm (from the wrist to the muzzle of the barrel) is reduced. this will increase muzzle flip. no effect on recoil, though.

shooting the same load in the same gun with at shorter barrel will increase recoil, increase muzzle blast and increase muzzle flip. imop

murf
 
Does a known load create the same amount of force regardless of the length of the barrel or weight of the gun?
 
While the bullet is moving slower in a short barreled pistol, there are a few other things that make recoil more severe.

1) Less weight and COG further back.
2) Higher pressure differential between the gas in the barrel and atmospheric (creates a jet effect). If you look at a pressure profile graph the longer the barrel the lower the gas pressure at exit. This means less jet effect.

I actually think #2 has more to do with the increased recoil than #1.
 
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