Long Range Hunting Online Magazine Barrel Length and Bullet Velocity Ratio
 Home LRH Store Forums Long Range Rifles Articles Reviews Video G7 Ballistics Calculator Rules & FAQ Register Search Today's Posts Mark Forums Read

# Barrel Length and Bullet Velocity Ratio

#1
05-07-2013, 12:11 PM
 Silver Member Join Date: Nov 2012 Location: Wyoming Posts: 229
Barrel Length and Bullet Velocity Ratio

Alright I need some experienced input...

The way I've seen it/been taught to see it is that 1" of added barrel length will result in about 50 fps added velocity... But I've recently read a few articles that seem to suggest otherwise.

For example: The way I was told, a given bullet which will reach 3000 fps from a 28" barrel will probably be capable of about 3050 fps from a 29" barrel given that the other elements are roughly the same (powder charge, primer, twist rate, bullet weight, etc...)

Is this a correct method of thinking or is it not even close to correct?? How much does it differ with different cartridges? If you could please give some examples from your own experience it would be much appreciated...

__________________

#2
05-07-2013, 03:44 PM
 Platinum Member Join Date: Feb 2009 Location: Sedalia, MO Posts: 1,240
Re: Barrel Length and Bullet Velocity Ratio

CB11WYO,

There's very little in this game that's linear, and this is yet another example of that. Velocity gain/loss in re barrel length varies substantially with the barrel lengths we're talking about, the expansion ratio (cartridge capacity), the bullet weight and many other factors which come into play. Bottom line is, it's all over the place, and virtually impossible to say that X increase or decrease in barrel length results in Y velocity change.

Sorry, and I wish there was a simple answer to this one, but the question is a little too broad for a single, concrete answer.
__________________
Kevin Thomas
Lapua USA
#3
05-07-2013, 04:41 PM
 Silver Member Join Date: Jan 2013 Location: Kansas Posts: 192
Re: Barrel Length and Bullet Velocity Ratio

Yea I agree, everything in shooting is relative. Logically it can and does increase velocity, but exactly how much depends on your rifle.
__________________
Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety.
-Benjamin Franklin
#4
05-08-2013, 02:36 AM
 Silver Member Join Date: Jan 2009 Location: Sweet Home OR Posts: 160
Re: Barrel Length and Bullet Velocity Ratio

I agree. There is no positive way to calculate what velocity you will get. Example i have a savage 308 with a 26" barrel. It shoots a 155gr amax at 2955 average on the last 5 shot string through my chrono. My buddy has a savage 308 with a 24" barrel. Same exact load same chrono on the same day. His 5 shot average was 2951. But I have a 168gr amax load that shoots 2870 out of my 308. The same load in my buddies rifle only shoots 2830. Hope my experience helps you out.
#5
05-08-2013, 10:29 AM
 Silver Member Join Date: Nov 2012 Location: Wyoming Posts: 229
Re: Barrel Length and Bullet Velocity Ratio

Quote:
 Originally Posted by Kevin Thomas CB11WYO, There's very little in this game that's linear, and this is yet another example of that...
That's what I was afraid of... oh well

Thanks!
__________________

#6
05-08-2013, 10:31 AM
 Silver Member Join Date: Nov 2012 Location: Wyoming Posts: 229
Re: Barrel Length and Bullet Velocity Ratio

Quote:
 Originally Posted by luke I agree. There is no positive way to calculate what velocity you will get. Example i have a savage 308 with a 26" barrel. It shoots a 155gr amax at 2955 average on the last 5 shot string through my chrono. My buddy has a savage 308 with a 24" barrel. Same exact load same chrono on the same day. His 5 shot average was 2951. But I have a 168gr amax load that shoots 2870 out of my 308. The same load in my buddies rifle only shoots 2830. Hope my experience helps you out.
Yup! Thanks that's a good example.
__________________

#7
05-08-2013, 10:32 AM
 Silver Member Join Date: Nov 2012 Location: Wyoming Posts: 229
Re: Barrel Length and Bullet Velocity Ratio

Just too many variables to work with, too many gun "personalities" in the mix I guess.
__________________

 Bookmarks

 Thread Tools Display Modes Linear Mode

 Current Poll Do you wear hearing protection while hunting? Usually do Usually do not No but I probably will in future
 Current Poll - 2 Do you have a high speed Internet connection? Yes, DSL, satellite, wireless or something else. - 89.18% No, only dialup right now. - 10.82% Total Votes: 3,042You may not vote on this poll.

All times are GMT -5. The time now is 02:52 PM.