16inch Barrel Sniper Rifles

[Niles Coyote]

Re: 16inch Barrel Sniper Rifles

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: haldir</div><div class="ubbcode-body">HOW much velocity do you gain per inch in a 308 anyway?</div></div>

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: modifier</div><div class="ubbcode-body">~25 FPS loss per inch cut seems about the norm.</div></div>

Good reading on the subject. http://www.tacticaloperations.com/SWATbarrel/

 

[00037]

Re: 16inch Barrel Sniper Rifles

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Niles Coyote</div><div class="ubbcode-body">Good reading on the subject. http://www.tacticaloperations.com/SWATbarrel/ </div></div>
Agreed. I bought a 20" because of that exact article.

 

[JamieD]

Re: 16inch Barrel Sniper Rifles

My .223 is 22" and have done a couple .308's set back to between 22" and 20". All seem to like them. My .223 is a tack driver and an SPS tactical we cut to 20" and put in a AICS shoots really well. I would go for it.

JamieD

 

[kombayotch]

Re: 16inch Barrel Sniper Rifles

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: modifier</div><div class="ubbcode-body">~25 FPS loss per inch cut seems about the norm. </div></div>

There is no fixed loss for any caliber unless you're talking about one specific load. Its a function of bullet weight, charge weight and how fast the powders is relative to the bullet weight.

When going from my 26" barrel to my 22" barrel, I lose about 25 fps. TOTAL with my 42.3 Varget + 190 load. But, I lose around 200 fps. on my 48.0 Varget + 110 VMAX load.

The VMAX load has much more powder to burn and the load was running at lower pressure since Varget is relatively slow for that bullet weight. There is still powder to burn at the end of the 22" tube (apparent from the muzzle blast). However, the 190 load has a relatively complete powder burn within the 22" barrel, so it loses almost nothing.

Shorter barrels will do better with faster burning powders. This hits the nail right on the head:

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Niles Coyote</div><div class="ubbcode-body">I have a 10” barreled 223 handgun and the blast was uncomfortable when I used my normal rifle load, switching to a faster burning propellant reduced the blast significantly without much change in velocity. </div></div>

 

[00037]

Re: 16inch Barrel Sniper Rifles

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: kombayotch</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: modifier</div><div class="ubbcode-body">~25 FPS loss per inch cut seems about the norm. </div></div>

There is no fixed loss for any caliber unless you're talking about one specific load. Its a function of bullet weight, charge weight and how fast the powders is relative to the bullet weight.</div></div>
Agreed. Every smith I've spoken with about .308 barrel lengths usually says one can expect about 25 FPS per inch with factory ammo. As with anything, there are variables involved and my (general) statement didn't account for reloading. When custom loads are involved, mileage WILL vary.