How much velocity will I lose cutting a 24" .308 barrel down to 22"? I anticipate running 168 gr SMKs and working up a load, starting around 42 gr. IMR 4895, which shoot well out of my FNAR (20" barrel).
Joe
Joe
how far can I cut down a .308 barrel
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Re: how far can I cut down a .308 barrel
With that load, nothing. Hell go 18" still 20ish fps
http://www.tacticaloperations.com/SWATbarrel/
With that load, nothing. Hell go 18" still 20ish fps
http://www.tacticaloperations.com/SWATbarrel/
Re: how far can I cut down a .308 barrel
I'm on the fence about going 18 or 16.5 inches my upcoming build... Not a long range piece more like 500-600 meter toy.
I'm on the fence about going 18 or 16.5 inches my upcoming build... Not a long range piece more like 500-600 meter toy.
Re: how far can I cut down a .308 barrel
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rprecision</div><div class="ubbcode-body">With that load, nothing. Hell go 18" still 20ish fps
http://www.tacticaloperations.com/SWATbarrel/
</div></div>
Like I said, I'm going to start at 42... of course I'm looking for more velocity if it agrees with the rifle, but 42 is what works in my FNAR, so I'm going to start there.
At what muzzle velocity will I start losing more going from 24" to 22" or shorter?
Joe
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rprecision</div><div class="ubbcode-body">With that load, nothing. Hell go 18" still 20ish fps
http://www.tacticaloperations.com/SWATbarrel/
</div></div>
Like I said, I'm going to start at 42... of course I'm looking for more velocity if it agrees with the rifle, but 42 is what works in my FNAR, so I'm going to start there.
At what muzzle velocity will I start losing more going from 24" to 22" or shorter?
Joe
Re: how far can I cut down a .308 barrel
I would guess 20" with that load. But theres alot of variables here, barrel, bore and groove, etc.
Go run the balistics of + - 100 FPS or even 50
I think that will outline how simple your decision is
I would guess 20" with that load. But theres alot of variables here, barrel, bore and groove, etc.
Go run the balistics of + - 100 FPS or even 50
I think that will outline how simple your decision is
Re: how far can I cut down a .308 barrel
In my experience, a 20" custom barrel & chamber is just as fast as a factory 24-26" barrel. Going from 24" to 22" the difference is going to be minimal.
In my experience, a 20" custom barrel & chamber is just as fast as a factory 24-26" barrel. Going from 24" to 22" the difference is going to be minimal.
Re: how far can I cut down a .308 barrel
Hell just cut it down to 12.5, screw velocity or terminal ballistics!
Hell just cut it down to 12.5, screw velocity or terminal ballistics!
Re: how far can I cut down a .308 barrel
That would look funny hanging out of the McRee Chassis.
Joe
That would look funny hanging out of the McRee Chassis.
Joe
Re: how far can I cut down a .308 barrel
Plenty of people running 20" 308s, myself included, and doing just fine out to 1K and beyond. With 178s I dont go subsonic till 1100 outta my factory Remington barrel at 20".
Plenty of people running 20" 308s, myself included, and doing just fine out to 1K and beyond. With 178s I dont go subsonic till 1100 outta my factory Remington barrel at 20".
Re: how far can I cut down a .308 barrel
Since you'll be cutting your barrel, your load will start over. Personally, I'd go with Varget and don't worry about the velocity difference...varget was made for short barrels
Since you'll be cutting your barrel, your load will start over. Personally, I'd go with Varget and don't worry about the velocity difference...varget was made for short barrels
Re: how far can I cut down a .308 barrel
I heard that NAA was planning a mini revolver in 308. 1.125" bbl, yeeehaw
I heard that NAA was planning a mini revolver in 308. 1.125" bbl, yeeehaw
Re: how far can I cut down a .308 barrel
If some hard data helps from actual chrono data, there is approximately a 120 FPS different in a 1 in 10, 16" to a 1 in 10 20" barrel (168g A-MAX, 44.8g Varget, ~75F, 2500 DA). Results will vary of course, but this is a good benchmark.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: seanh</div><div class="ubbcode-body">Since you'll be cutting your barrel, your load will start over. Personally, I'd go with Varget and don't worry about the velocity difference...varget was made for short barrels </div></div>
Like Seanh said, Varget is a fast powder. You shouldn't see much of a MV drop at all for what you are trying to do.
If some hard data helps from actual chrono data, there is approximately a 120 FPS different in a 1 in 10, 16" to a 1 in 10 20" barrel (168g A-MAX, 44.8g Varget, ~75F, 2500 DA). Results will vary of course, but this is a good benchmark.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: seanh</div><div class="ubbcode-body">Since you'll be cutting your barrel, your load will start over. Personally, I'd go with Varget and don't worry about the velocity difference...varget was made for short barrels </div></div>
Like Seanh said, Varget is a fast powder. You shouldn't see much of a MV drop at all for what you are trying to do.
Re: how far can I cut down a .308 barrel
for reference I was getting 2600ft/sec out of a 16" gas gun with PP2000mr with a 168gr a-max 1gr below max.
for reference I was getting 2600ft/sec out of a 16" gas gun with PP2000mr with a 168gr a-max 1gr below max.
Re: how far can I cut down a .308 barrel
i think a medium range short (16.5") bolt gun with a can would be fun as shit... I have seen several, a frind of mine is having one built as soon as he gets his .30cal can.
I have no problem building a gun for each shooting purpose i have.
i think a medium range short (16.5") bolt gun with a can would be fun as shit... I have seen several, a frind of mine is having one built as soon as he gets his .30cal can.
I have no problem building a gun for each shooting purpose i have.
Re: how far can I cut down a .308 barrel
I run a 17.25 on a 700. Varget powder and a 168 hornady match. Muzzle vel 2673 fps. It has taken top 308 at the last 2 local PR matches. There is only one draw back. The ROs keep complaining its loud. But its too much fun to shoot.
I run a 17.25 on a 700. Varget powder and a 168 hornady match. Muzzle vel 2673 fps. It has taken top 308 at the last 2 local PR matches. There is only one draw back. The ROs keep complaining its loud. But its too much fun to shoot.
Re: how far can I cut down a .308 barrel
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: hsss</div><div class="ubbcode-body">The ROs keep complaining its loud.</div></div>
Perhaps they misunderstand what standing on a rifle range entails. They're fucking rifles! Of course they are loud!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: hsss</div><div class="ubbcode-body">The ROs keep complaining its loud.</div></div>
Perhaps they misunderstand what standing on a rifle range entails. They're fucking rifles! Of course they are loud!
Re: how far can I cut down a .308 barrel
I just cut my Savage 10 down from 24" to 20" and it shoots much better. Overall, I only lost about 52fps but after doing my load development, it liked a slightly hotter charge which counter-acted the loss from shortening the barell. Also, if your planning on shooting suppressed, having the shorter barrel definatley gives the rifle a better balance if shooting offhand (comps).
BTW: I shoot 168 A-Maxs w/ 42.7gn Varget. If I do my part it will now punch 1 hole groups. Before cutting it down it would not.
I just cut my Savage 10 down from 24" to 20" and it shoots much better. Overall, I only lost about 52fps but after doing my load development, it liked a slightly hotter charge which counter-acted the loss from shortening the barell. Also, if your planning on shooting suppressed, having the shorter barrel definatley gives the rifle a better balance if shooting offhand (comps).
BTW: I shoot 168 A-Maxs w/ 42.7gn Varget. If I do my part it will now punch 1 hole groups. Before cutting it down it would not.
Re: how far can I cut down a .308 barrel
I cut 4" off and target crowned it.
I'm heading out to try it at 20" now.
I see a lot of Hiders like Varget in the .308.
I4895 is slightly faster burning so it should work similarly in shorter barrels, and I have two 8 lb. containers of it so it's what I'm using at the moment.
Joe
I cut 4" off and target crowned it.
I'm heading out to try it at 20" now.
I see a lot of Hiders like Varget in the .308.
I4895 is slightly faster burning so it should work similarly in shorter barrels, and I have two 8 lb. containers of it so it's what I'm using at the moment.
Joe
Re: how far can I cut down a .308 barrel
I shoot a 18" heavy PSS in .308 that is threaded 5/8 X 24 for a suppressor and my Vortex Flash Hider. I ONLY use Black Hills 175 Match and it WILL do the job to 1K.
Like someone mentioned above... ITS LOUD.. and you deal feel MORE recoil at the shorter barrel lengths. But the benefit is a VERY compact rifle that is VERY packable and carriable ALL day long.
Matt (LEO SOUTH GA.)
I shoot a 18" heavy PSS in .308 that is threaded 5/8 X 24 for a suppressor and my Vortex Flash Hider. I ONLY use Black Hills 175 Match and it WILL do the job to 1K.
Like someone mentioned above... ITS LOUD.. and you deal feel MORE recoil at the shorter barrel lengths. But the benefit is a VERY compact rifle that is VERY packable and carriable ALL day long.
Matt (LEO SOUTH GA.)
Re: how far can I cut down a .308 barrel
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jbjh</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: hsss</div><div class="ubbcode-body">The ROs keep complaining its loud.</div></div>
Perhaps they misunderstand what standing on a rifle range entails. They're fucking rifles! Of course they are loud!</div></div>
No, SPL from short barrels is just annoying...add to that a muzzle break...even more annoying.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jbjh</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: hsss</div><div class="ubbcode-body">The ROs keep complaining its loud.</div></div>
Perhaps they misunderstand what standing on a rifle range entails. They're fucking rifles! Of course they are loud!</div></div>
No, SPL from short barrels is just annoying...add to that a muzzle break...even more annoying.
Re: how far can I cut down a .308 barrel
I went from a 24" to an 18" barrel and my velocity dropped about 150fps - most say that you lose 25 - 30 fps per inch of barrel cut.
I went from a 24" to an 18" barrel and my velocity dropped about 150fps - most say that you lose 25 - 30 fps per inch of barrel cut.
Re: how far can I cut down a .308 barrel
I'm going to go 16". I figure since the difference to the trans-sonic death spiral with a 175SMK is only 130 yards with the bullet going 2500/2750fps low/high, according to shooter, why go longer than 16" unless it's 26"/dedicated .308 only match rifle.
I too plan to run a can but not in a match setting.
I'm going to go 16". I figure since the difference to the trans-sonic death spiral with a 175SMK is only 130 yards with the bullet going 2500/2750fps low/high, according to shooter, why go longer than 16" unless it's 26"/dedicated .308 only match rifle.
I too plan to run a can but not in a match setting.
Re: how far can I cut down a .308 barrel
I had an 18" with Surefire brake. I could not get 178's to cooperate, but 175MK's worked with both RL15 and XBR with XBR yielding a velocity of 2630. It did well for the most part, but I will be returning to longer barrels.
I had an 18" with Surefire brake. I could not get 178's to cooperate, but 175MK's worked with both RL15 and XBR with XBR yielding a velocity of 2630. It did well for the most part, but I will be returning to longer barrels.
Re: how far can I cut down a .308 barrel
26" IBA rifle was running 2720.
20" set back factory barrel (rechambered with shorter freebore, cut from 26 to 20") was running same load at 2620.
Figure about 17 fps/in you cut off.
Typically you can't get a gasser to run the same load a bolt rifle w/o beating up the brass and/or rifle.
Check with Pusher951, he had a 17" barreled 308 but I forget the velocity he was seeing with 175/178s but want to say it was in the 2550 range.
26" IBA rifle was running 2720.
20" set back factory barrel (rechambered with shorter freebore, cut from 26 to 20") was running same load at 2620.
Figure about 17 fps/in you cut off.
Typically you can't get a gasser to run the same load a bolt rifle w/o beating up the brass and/or rifle.
Check with Pusher951, he had a 17" barreled 308 but I forget the velocity he was seeing with 175/178s but want to say it was in the 2550 range.
Re: how far can I cut down a .308 barrel
I took my rifle out to compare some velocity differences between Win and Lapua cases and the same load. While I still have to write this up for my rifle here, are the results. For me, the 190 SMK's are shooting fantastic from my 21" TacOps.
I took my rifle out to compare some velocity differences between Win and Lapua cases and the same load. While I still have to write this up for my rifle here, are the results. For me, the 190 SMK's are shooting fantastic from my 21" TacOps.
