Woollybugger
Gold $$ Contributor
Berger says 8 Twist or faster for their (now discontinued) 55gr 20cal
20 cal guys
- Thread starter chuckshooter
- Start date
Indeed it does but most people have found that unless the 55’s are being used at low velocity that 1-9” works great and there’s less chance of bullet blow ups. Several folks built 20 BR’s (or bigger cases) with 1-8” twist only to have bullets vaporize before connecting with the target. I suspect Berger assumed someone would try the 55 in a VarTarg.
Gabe22BR
Gold $$ Contributor
20BRAI
Maybe someone may find this information useful? My barrel is an 8.5-8 Bartlein gain twist. I started using Alpha 6BRA brass, 205M primer. 29grs RL15 heavy bolt lift. 28.5 is running 3550fps, Id say this is max in my setup. I've tried AR Comp, VV150, VV160. 31grs of VV550 is giving me...
forum.accurateshooter.com
1-9 twist kreiger -28-1/2” HV 1.1 at muzzle
You the judge:
If your going 20GT= more powder than a Dasher- might get away w/ 1-10” twist… with 55gr bullets
Which Grafs has in-stock right now !!!!
from a once a yr run… there not discounted..!!!
Gabe22BR
Gold $$ Contributor
I have- found them to be awesome in my 1-8” 20VT improved !!!!
No question about it Gabe! And I’m sure you are glad you went with 1-8” with that combo!
chuckshooter
Silver $$ Contributor
Do you think a 10t will work with 40vmax,, 6br.. I have a bunch of 40's I need to shoot. I've got the barrel, reamer, bullets and brass. So might as well spin it up. Or do I need a 9t?
Coyotefurharvester
Silver $$ Contributor
A 1 in 11 will handle all the 40's and the discontinued Hornady 45 sp. Thompson Center used 1\10 twist barrels for their 204R. The 20vt will be fine with a 1 in 11.
nakneker
Gold $$ Contributor
If you do please share the details. I’m curious how a 20 GT would go.
Gabe22BR
Gold $$ Contributor
1-10 work with any current 20 cal bullets available today. You know that…
I too be curious of the load work on 20GT..
7315br
Silver $$ Contributor
My $.02 worth. Several years ago I decided to build a .20/250 on a Kreiger HV 10-twist (set-up for the 55 gr Berger). I live at a higher elevation (over 5,000') and wanted to use it for PD's in Wyoming (up to 7,000' elevation).
I was trying to get longer barrel life with the slower twist since many folks had had issues with 1:8 twist bbls. and the 55 gr Berger (particularly with bullets blowing up at velocities above 3750 fps). The rifle I built (3830 fps max) on a RFD action worked out well, and was very accurate (several PD's taken over a 1000 yds)...but barrel life was not impressive. I ended up changing the barrel out after 417 rds due to excessive throat erosion.
I've had a number of .20BR's (all for the 55 gr Berger) 1:9 twist bbls. Barrel life is normally 900-1000 rds. I had one that went 1500 rds. I've settled on the .20 PPC as the largest .20 caliber for decent bbl life. Best of luck.
I was trying to get longer barrel life with the slower twist since many folks had had issues with 1:8 twist bbls. and the 55 gr Berger (particularly with bullets blowing up at velocities above 3750 fps). The rifle I built (3830 fps max) on a RFD action worked out well, and was very accurate (several PD's taken over a 1000 yds)...but barrel life was not impressive. I ended up changing the barrel out after 417 rds due to excessive throat erosion.
I've had a number of .20BR's (all for the 55 gr Berger) 1:9 twist bbls. Barrel life is normally 900-1000 rds. I had one that went 1500 rds. I've settled on the .20 PPC as the largest .20 caliber for decent bbl life. Best of luck.
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Gabe22BR
Gold $$ Contributor
Anyone else notice that Parkwest arms is now offering custom chambering, wood up grades or synthetic, custom serial#, checkering, metal choices, engraving…etc… Since Cooper isn’t going to be the same…
I personally think the old Cooper had something, since it’s gone , I don’t see the value there anymore, for replacement parts, or rebarreling, fp springs, or other normal wear/tear from being stored …
Wish I had the $$$ to send my reamer, & build my dream one…
I personally think the old Cooper had something, since it’s gone , I don’t see the value there anymore, for replacement parts, or rebarreling, fp springs, or other normal wear/tear from being stored …
Wish I had the $$$ to send my reamer, & build my dream one…
Fern
Silver $$ Contributor
Friends dad was telling me that his good friend bought a cooper and had several issues with it. Believe he said the safety didn’t work and when you chambered a round it it would fire without touching the trigger.
He called them up and they offer no support would not take it back and he is basically left with an unfair rifle till he can find someone to work on it.
My friends dad has couple older coopers and he loves them but will not buy another one with what they have become
Rick in Oregon
Gold $$ Contributor
This is one of those sad stories of a great rifle company selling out to another who's interest in saving what made the brand famous and was considered to be "one of the best" to be not their priority. With the sale of Cooper to NH Custom, we'll never see the old solid bottom single shots with great wood that put their name on the map so to speak.
It appears NH is more into the "tacticool" than traditional. I've got four original Coopers, there will not be another from NH.
nakneker
Gold $$ Contributor
I wish I felt like your sentiments weren’t true, unfortunately I’m afraid they are spot on.
TAJ45
Silver $$ Contributor
A good bud womped up a long neck 6XC, right at .400 long. He likes warp speed. The long neck gave him less than .004 throat wear after 700 rds and superb accuracy. It is called the Turbulence Point where the shoulder angles meet in the neck. His 6mm AI Rems always outlasted his 243AIs, even burning 2-3 gr more power. Back then he always shot top quality bbls, Hart etc. He left the shldr angle at 30°. We didn't pop for a new 35° reamer :/. He pushed 107s at 3350 or better w great brass life on the Lapua Palma srp.
AFA the easy peasy, 20 Prac - plentiful cheap brass. The 20 222 a close second imo.
SBS
Gold $$ Contributor
Absolutely, just took me several years to recognize those 2 wonderful chamberings. Pushing 4000 in the .20 Prac. and over 3900 in the .20-222 with the 32 grainers.
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