Recoil influenced by barrel length?

[Arp32]

I was shooting a few .308 and .30-06 rifles the other day and really noticed the difference in recoil for the first time due to an awkward bench position (I was on the "wrong" side of the table due to a full range). Usually I have a little better form and I tuck it in more firmly so I don't feel sore after.

Question occurred to me, do you experience more felt recoil in the short barreled rifles (like an FR-8 Spanish Mauser in .308) solely due to the reduced weight of the rifle, or does the shorter barrel have anything to do with it?

I've always thought it was just a weight issue, but another shooter at the range commented that he didn't like the recoil of those "short barreled" rifles.

 

[Z-Michigan]

Longer barrel = more bullet velocity = more momentum = more actual recoil force

felt recoil is heavily dependent on recoil speed which is directly related to the rifle weight. A heavier rifle will have less recoil speed and therefore (usually) less felt recoil. If you assume the shorter barreled rifle is lighter, which is not always the case, then it could have more felt recoil despite the lower bullet velocity

Also,

shorter barrel = more blast and louder report = more perception of recoil by many shooters

Many shooters, even experienced ones, "feel recoil" based more on the blast than on the actual force on their shoulder. With magnum calibers or very short barrels (16" and less) this can be severe.

 

[NG VI]

Well I don't expect that the length would change the recoil, though it does change the amount of concussion coming from the muzzle and the shorter barrels with more of it will also place the point of origin closer to the shooter.

Could change recoil characteristics as well, maybe a rifle with a much shorter barrel/overall length but the same weight as a longer rifle with a totally different balance would feel different. Shorter rifle may have a different style of roll or whip, which would feel a little different even though the actual recoil is the same.

 

[56hawk]

Well, I was bored so I did some calculations on this. It would seem that the weight lost from shortening a barrel is almost an exact match to the velocity loss. Looking at shortening a barrel from 26" to 16" resulted in only a ±3% change in recoil energy.

 

[Arp32]

Michigan, everything you said makes sense. I'd agree with you on the noise factor, no doubt it can make you flinch if you're not used to it. I did feel it in my shoulder, though, so I'm thinking there was more to it. Or maybe I just had poor form on a couple shots and gave myself a little bruise. I've shot a couple hundred rounds through that rifle over the past year and never noticed a difference before.

Hawk, probably a lot of variables to keep track of. I believe in math, but it would be interesting to test out something like a full size M1A alongside a SOCOM M1A.

 

[tahoe2]

recoil

today I shot a

Winchester M70 featherweight in .284 win w/145grn bullet 22" Bbl
Savage Model 99F in .300 Savage w/165 grn bullet 24" Bbl and a
Marlin 375 in .375 Winchester w/220 grn bullet 20" Bbl

the first two pretty much the same( both weighed about 8# with scope) the Marlin (7# with scope) was quite notably heavier recoil than the other two.
not painful, but still I was pretty amazed at the difference.
That Marlin was Stout !! It was a great day-recoil lets you know you're alive !!

 

[murf]

if you don't "tuck it in more firmly", the rifle will get a running start at your shoulder. there will be an increase in the felt recoil.

murf

 

[Sav .250]

IMO......no

 

[Z-Michigan]

today I shot a

Winchester M70 featherweight in .284 win w/145grn bullet 22" Bbl
Savage Model 99F in .300 Savage w/165 grn bullet 24" Bbl and a
Marlin 375 in .375 Winchester w/220 grn bullet 20" Bbl

the first two pretty much the same( both weighed about 8# with scope) the Marlin (7# with scope) was quite notably heavier recoil than the other two.
not painful, but still I was pretty amazed at the difference.
That Marlin was Stout !! It was a great day-recoil lets you know you're alive !!

Interestingly enough my 18" .308 recoils more than my 20" .223.... amazing!

 

[PedalBiker]

I've found that noise level and felt recoil pretty much track. I'm not sure it's this way for everyone.

Also, even though the bullet is going somewhat slower in a short barrel the powder gasses get uncorked at a higher pressure so their contribution to recoil will be higher unless you have a brake.

I have a .260 that I cut from 24" to 19". I don't notice much difference in recoil, but the rifle was a lot more pleasant to shoot before.

 

[jmr40]

It is math really. Recoil is determined by calculations involving 4 things.

Bullet velocity---More velocity= more recoil.
Rifle weight---More weight= less recoil.
Powder weight.---More powder= more recoil.
Bullet weight---More weight= more recoil

Added info in red. I had a brain fart and left out bullet weight.

If you reduce the velocity and keep the rifle weight the same, recoil would be less. But by cutting to a shorter barrel, you also reduce weight, so it may well even out as a previous poster noted.

If you can find another powder that will give you equal velocity with less powder that will also reduce recoil.

One reason the 308 seems to recoil less is that it uses less powder to get nearly the same velocity as a 30-06. The 308 case design allows for more efficient burning of the powder.

 

[PedalBiker]

I would add one more element to your list.

Gas velocity (can be over 2x or more bullet velocity).

The powder charge weight, therefore, gets a higher multiplier than the bullet weight.

 

[JustinJ]

How can bullet velocity directly influence recoil? I'm just speculating here but a longer barrel, assuming weight being equal, would probably have higher recoil as more of the energy from the expanded gas is imparted on it since the force continues for a longer period of time before being released into the atmosphere. Once the expanding gasses exit the muzzle they are no longer acting on the rifle(assuming no break or compensator is used) so the longer they act on it the more recoil. A longer barrel is essentially using the force from the expanding gas more efficiently.

 

[jmr40]

There are online programs to calculate recoil.

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

Just plug in the rifles weight, bullet weight, velocity, weight of the powder charge.