Visit the SWFA.com site to check out our current specials. |
1:8 Twist 308 Win |
Post Reply |
Author | |
nralifer
Optics Apprentice Joined: July/26/2016 Status: Offline Points: 165 |
Post Options
Thanks(0)
Posted: February/11/2018 at 04:27 |
Testing this weekend a wild hair idea of chambering a 308 Win in an 8 twist 18 inch barrel to have a gun that has the power of a 3006 and can shoot subsonic and use a 6" suppressor. So far I have gotten average 2947 fps using the 155 Palma bullet with WLRM primers and 49 gr Leverevolution. The subsonic load is a 204 gr ICBM in front of 15 gr Trail Boss ignited with the WLRM primer generating an MV of 1081 fps.
Edited by nralifer - February/11/2018 at 04:40 |
|
It is hard to fail, but it is worse never to have tried to succeed. TR
|
|
Kickboxer
MODERATOR Moderator Joined: February/13/2008 Status: Offline Points: 23679 |
Post Options
Thanks(0)
|
Wow... outstanding. You know, you are going to force me to start reloading again, yet...
|
|
Opinion,untempered by fact,is ignorance.
There are some who do not fear death... for they are more afraid of not really living |
|
koshkin
MODERATOR Dark Lord of Optics Joined: June/15/2004 Location: United States Status: Offline Points: 13181 |
Post Options
Thanks(0)
|
2947fps out of a 18" 308Win barrel with a 155gr bullet?
That's faster than is typical for a 24" barrel with 155gr bullets. One of these days you will blow yourself up. I've had a rifle blow up in my hands once and I did not enjoy that one bit. ILya
|
|
SVT_Tactical
MODERATOR Chief Sackscratch Joined: December/17/2009 Location: NorthCackalacky Status: Offline Points: 31233 |
Post Options
Thanks(0)
|
I did the whole 308 subsonic thing for a bit.... 16" barrel, but found with the blackout now, not much reason to go load 308 sub rounds that aren't as constant as I liked when shooting subs. a 30cal projectile fired at the same speeds will yield the same results if the same weights.... the blackout bolt gun does it better than the 308 bolt gun when it comes to subs....IMO Loading the 308 to 30-06 levels you are going to blow something up, just a matter of when. |
|
"Most folks are about as happy as they make their minds up to be" - Abraham Lincoln
|
|
jonoMT
Optics Master Extraordinaire Joined: November/13/2008 Location: Montana Status: Offline Points: 4853 |
Post Options
Thanks(0)
|
If I hear a loud boom to the east at least I'll know what it was.
|
|
Reaction time is a factor...
|
|
nralifer
Optics Apprentice Joined: July/26/2016 Status: Offline Points: 165 |
Post Options
Thanks(0)
|
Well, guys don't worry. I have been using a similar load for a long time in my 10 twist 308. The new rifle we tested was one that a friend of mine and I thought up. He sells actions for ARC. The gun has a Proof Research 8 twist and is 18" long. The load is Jason's 155 gr ICBM, with 50.5 grains of LVR using BR4 primers and Lapua small rifle primer loaded to a 2.880 COL. MV is 2960, and grouped 0.30" at 100 yds. There was no primer flattening, no extraction problem, no enlargement of the primer pocket and no shiny spots on the brass. The subsonic load was 12.7 gr Trail Boss using a 188 gr ICBM bullet at 1020 fps. It produced 0.5"groups at 100 yds and with 35MOA elevation one could hit a 10" gong 10/10 shots at 300 yds. on a windy day. The 204 gr ICBM did not shoot with consistent velocities I think because the bullet is long and compressed the TB powder which behaves erratically when compressed. The gun shows the extreme versatility of the 308 Win with good bullets and a tight twist barrel. The Leverevolution powder is an excellent one and is the reason we get such velocities with our bullets. The 155 gr ICBM and the 150 gr Bulldozer have a reduced bearing surface and when tested against other 150s on the market have a 50 fps advantage in MV. That Proof Research barrel is one sweet tube. With a 6" suppressor the subsonic loads are quieter than a pellet gun. Fun stuff!!
|
|
It is hard to fail, but it is worse never to have tried to succeed. TR
|
|
338LAPUASLAP
Optics Master Scope Swapper Joined: October/17/2009 Status: Offline Points: 2596 |
Post Options
Thanks(0)
|
Interesting.
|
|
No one
|
|
koshkin
MODERATOR Dark Lord of Optics Joined: June/15/2004 Location: United States Status: Offline Points: 13181 |
Post Options
Thanks(0)
|
I triied both of those bullets in my 24" Proof carbon fiber sleeved barrel and I am getting about 3050fps with the 155gr ICBM Palma bullet and around 3100fps with the 150gr Bulldozer.
I still think George's 2950fps out of an 18" tube is a bit hot, but it is not as dangerous as I originally though. Going to a faster twist rate is an interesting idea. With the right bullet construction, faster twist will increase lethality. I am looking at getting a Blackout with a 1 in 5" twist or faster if I can find one. ILya
|
|
supertool73
Optics God Superstool Joined: January/03/2008 Status: Offline Points: 11814 |
Post Options
Thanks(0)
|
A 5" twist? Curious about that one, fill us in.
|
|
Lifetime warranty and excellent customer service don't mean a thing when your gun fails during a zombie attack.
"A Liberal is a person who will give away everything they don't own." |
|
koshkin
MODERATOR Dark Lord of Optics Joined: June/15/2004 Location: United States Status: Offline Points: 13181 |
Post Options
Thanks(0)
|
In due time. ILya
|
|
Urimaginaryfrnd
MODERATOR Resident Redneck Joined: June/20/2005 Location: Iowa Status: Offline Points: 14964 |
Post Options
Thanks(0)
|
https://www.ruger.com/products/americanRifleRanch/specSheets/26968.html Ruger is 1 in 7
|
|
"Always do the right thing, just because it is the right thing to do". Bobby Paul Doherty Texas Ranger |
|
SVT_Tactical
MODERATOR Chief Sackscratch Joined: December/17/2009 Location: NorthCackalacky Status: Offline Points: 31233 |
Post Options
Thanks(0)
|
Do any barrel makes offer a 5 twist in a 30cal tube?
|
|
"Most folks are about as happy as they make their minds up to be" - Abraham Lincoln
|
|
chase102798
Optics GrassHopper Joined: July/11/2010 Location: PA Status: Offline Points: 12 |
Post Options
Thanks(0)
|
Q and Sig both make short barrels with 1-5. Xcaliber barrels will make you one in 1-5. Try it. You will like it.
|
|
Stiller3.43
Optics GrassHopper Joined: November/04/2014 Status: Offline Points: 11 |
Post Options
Thanks(0)
|
WOW!!! I can't believe that is as fast as you are getting with 15 gr. of TB. on those 204 gr. bullet with an 18 in. barrel. I have a 1-7 twist on my 308 and a 14inch barrel. 11.5 gr of TB puts me at 1041 fps with 208 gr. I also get 2407 fps with 44 gr. BLC2 with 168 gr. match. I have a GemTech that I run on it and it is sexy. Very low vis. |
|
"I'm just a monkey on a gun"
-Chris Kyle |
|
Steelbenz
Optics Jedi Knight ROLL TIDE ROLL Joined: January/03/2006 Location: Heart of Dixie Status: Offline Points: 5153 |
Post Options
Thanks(0)
|
Older thread, but the 204 ICBM is of all copper construction. That makes it lighter but longer that the Hornady. by a good .120 of an inch. thus the bearing surface is going to be significantly different between the two.
|
|
"Don't argue with a fool! From a distance you can't really tell who's who!"
|
|
Post Reply | |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |