Barrel Length vs Velocity

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Ammo Smith
Mar 11, 2013
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All the bench rest shooters and long range guys like long barrels to achieve max velocity with their loads.
But what about us hunters? What length barrel do you think we need to get the most out of hunting rifles?
My M700 Remington 35 Whelen has a 22" barrel and the best velocity I can get out of it 2750fps with a 200gr AB and is the reason I went to the 35 Whelen Ackely improved with a 24" barrel. ( Ackely chamber was an after thought since I thought I may as well go for the whole 9 yards when getting the barrel bored and rifled with no regrets) I didn't think I was getting the best out of the 35 Whelen with a 22" barrel and there are guys here who have 24" barrels on their Whelens who get higher velocities.
Granted I have more case capacity in the AI version but I'm not running it full throttle ( 58kpsi standard vs 60kpsi Ackely ) and get 200fps higher velocities than I can obtain in a 22" barrel. Is the 24" barrel optimum for this cartridge?
What would I gain in a 26" barrel with a standard 35 Whelen?
Some of you guys with the ballistics apps could help me out on this.
 
Since you stipulated that this is about a "hunting rifle," the current standard of 22 inches is about right. It allows the hunter to negotiate thicker brush without constantly hanging up. Twenty-four is about a maximum. The difference in velocities with each added inch of barrel length simply doesn't make that much difference in the field so far as lethality is concerned. I used to disdain 20 inch barrels; I've come around to see that in the real world that loss of two inches is insignificant.
 
DrMike it's amazing how we consider a 24"-26" rifle barrel long or too long for negotiating brush when most of us choose 28"-30" for the optimum length for our shot guns and hunt in heavy brush with them with no problems . I agree that short barrels are handier and have several shot guns with spare 26" barrels I hunt with but then again they are still longer than my rifles.
 
I think it's all personal preference. I run 22"-27" barreled hunting guns. I don't notice anything when I'm hunting. Shorter barrels are lighter by a little bit.

My wife thinks I only have 3 guns
 
I have 20 to 26" barreled rifles. 24 seems to be the sweet spot for me. Anything under the 24" feels like a carbine at my height and build. When I put together the 7 MSM it'll be a 25" tube.
 
It's not just barrel length for me, when it comes to hunting rifles. One of the reasons I like hunting with a Ruger Number One so well, is that with a 24" barrel, it's still about the same overall length as a 20" barreled lever action rifle:



Took that photo shortly after I got the .375 Number One a few years back. My oldest son has the nice old Belgian made .308 Browning BLR.

Guy
 
Oh, we've got a pair of .30-06 rifles here. My youngest son uses an old 1917 with the barrel cut down to 21" and mine is a relatively new 24" Rem 700.

With the same 165 gr ammo, my 24" barrel generates roughly 100 fps more than his 21" barreled rifle.

Guy
 
I'll have to see if I can dig up my velocity data. Years ago we had three .308 Win rifles here, with 20", 24" and 30" barrels...

Quite a spread in velocity too as I recall.

Guy
 
With a potential velocity gain/loss of 25-35 ft/sec per inch, barrel length is nearly irrelevant when it comes to velocity in a hunting rifle. Balance or personal preference is more of an issue IMO.

My shortest barrel is 18.5" on a Marlin 45-70, exactly the way I like it.
My longest barrel is 28" on a heavy LR varmint rifle. Part of the reason that I chose this length is so that I can set the barrel back after a 1,000 rounds (or so) and still have at least 26" of barrel left for the remaining life of the barrel. I shoot heavy for caliber bullets with slooooo powder and the longer barrel is needed.
 
Heavier for caliber bullets with slow burning powder, Will to days powder burn completely in the shorter barrels? Also we say the gain per inch is only 25-35fps difference but how much elevation or wind drift do we loose along with the loss of velocity?
I'm on a learning curve here since I have never payed attention to these things in the past and you guys have spiked my curiosity.
 
One interesting resource is Hodgdon's manual. Online or hard copy.

They have taken a bunch of different cartridges and tested them in 15" pistol barrels! Cartridges like the .308, .30-06 and more.

What seems to be the trend, from what I saw, is that the loads that generated the most velocity with 24" barrels, also produced the most velocity from 15" pistol barrels...

Guy
 
Guy Miner":2uw2u082 said:
One interesting resource is Hodgdon's manual. Online or hard copy.

They have taken a bunch of different cartridges and tested them in 15" pistol barrels! Cartridges like the .308, .30-06 and more.

What seems to be the trend, from what I saw, is that the loads that generated the most velocity with 24" barrels, also produced the most velocity from 15" pistol barrels...

Guy
If I understand you right the same fast burning powder produced higher velocities in both barrels. So you have to match the powder burn to the barrel length to achieve optimum performance?
 
Not really. An example is the .308 Win loaded with a max charge (46gr) of Varget and a 165 grain bullet:

15" barrel velocity is 2576 fps (highest velocity of pistol barrel loads)
24" barrel velocity is 2773 fps (highest velocity of the rifle barrel loads)

It's probably not true in all cases, but usually the powder that gives best velocity in a given cartridge, does very well in many different barrel lengths.

OH - and from the first post in this thread, only the LONG RANGE benchrest shooters prefer the real long barrels. The normal 100, 200, 300 yard BR competitors tend to favor shorter, stiffer barrels for max accuracy.

Regards, Guy
 
Seen the same. A fast powder in a long barrel is going to be fast in a short barrel.
 
The AccurateShooter web site has tests where they cut barrels down a inch at a time and check velocity. Also Rifleshooter.
 
Agree the fasted load in a long barrel will be the fastest in a shorter barrel. Have seen in it rifles and pistols. Basing powder choice on barrel length instead of the cartridge is a waste of more than time. If you end up with ejecta out of your barrel it's because the powder is inappropriate for the cartridge, not the barrel length. If you think it is unburned powder, try igniting it.
 
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