55 gr 20 cal Bergers in 20 BR. Velocity and twist?

[Tommie]

Working on a wildcat that will approximate the BR powder capacity. Berger recommends a 7" twist but I've read that some people are having success with 8" twist barrels. I'd be interested to know from folks running a similar setup what rifling twist they're using and how the measured velocities are measuring up.
TIA!

 

[hot range]

I use a 1-9 twist on mine with that set up. I believe you will find a lot of people that will say that is fast enough for the 20 br and 55 gr bergers. If you havnt ever talked to Todd Kindler I would recommend giving him a call. Google the woodchuck den and it will bring up his website.

 

[TAJ45]

I bought a 20 BR bbl from a methodical and intelligent shooter. With a 9 t w, even though some say they do, he never got accuracy much better than a half inch. I haven't had time to even set it up and try it out.

 

[MrMajestic]

I run a 8 1/2tw with a 5X45AI, .20-.223AI, .20 Practical AI or whatever else is want to call it. 3640 fps from a 28" barrel and haven't noticed any problems to 535 yards on Chucks and 640 on steel. B. Litz's s/w is spot on with come-ups also.

 

[Phil]

I would`t be afraid to run the .20cal. 55 in an 8 twist barrel for use in a .20BR.


Phil.

 

[JASmith]

The 20 Grendel is intermediate in powder capacity between the PPC and BR. I use an 8-twist with both 55 gr Bergers and Black Hole Diamond Tip bullets.

The limited tests to date indicate good accuracy and stability.

http://shootersnotes.com/articles/20-grendel/

I run 3100 -3150 fps because I'm keeping the pressures around 50,000 psi and use a 20" barrel.

 

[butler12]

Hi,
I have a 20BR built using a 3 grove 1 in 9 twist Pacnor barrel in Rem varmint contour finished at 27" and it is a super combination with 55gr bergers, Reloader 15 and CCI 450 .

 

[Tommie]

It's interesting that people are having such success with 8 and 9 twist barrels. Wonder why Berger is recommending 1-7"

 

[Phil]

It's interesting that people are having such success with 8 and 9 twist barrels. Wonder why Berger is recommending 1-7"

Insurance.

 

[Tommie]

Insurance.

Like if some someone wants to load 55's in his Vartarg...

 

[GAnderson]

I bought a 20 BR bbl from a methodical and intelligent shooter. With a 9 t w, even though some say they do, he never got accuracy much better than a half inch. I haven't had time to even set it up and try it out.

Hi Tom, would you believe I have another 20BR with a Benchmark 1-10 twist that is shooting the 55 Berger like a house of fire? Killed prairie dogs at 970 yards last year. Also shooting the 40gr BIB bullets and they are really awesome. Sometimes the twist thing just doesn't add up. You need to get that 9 twist going and see what you can do with it.
Regards,
Gene Anderson

 

[TAJ45]

Hi Tom, would you believe I have another 20BR with a Benchmark 1-10 twist that is shooting the 55 Berger like a house of fire? Killed prairie dogs at 970 yards last year. Also shooting the 40gr BIB bullets and they are really awesome. Sometimes the twist thing just doesn't add up. You need to get that 9 twist going and see what you can do with it.
Regards,
Gene Anderson

Hey Gary,
I'm back in IN now, will be residing SW of Seymour with abt 750 yds available. Keith is working up loads and brass for a brainstorm I had to mod an XC. More later friend. Tom

 

[Tommie]

Hi Tom, would you believe I have another 20BR with a Benchmark 1-10 twist that is shooting the 55 Berger like a house of fire? Killed prairie dogs at 970 yards last year. Also shooting the 40gr BIB bullets and they are really awesome. Sometimes the twist thing just doesn't add up. You need to get that 9 twist going and see what you can do with it.
Regards,
Gene Anderson

1-10" twist?! Ok, that blows the 1-7" recommended twist theory completely out of the water.

 

[GAnderson]

Tommie, I am not saying that it would be the norm but for some reason the 10 twist is handling the 55's. I have them into the lands about .005/.006 and it seems to work.

 

[Tommie]

Tommie, I am not saying that it would be the norm but for some reason the 10 twist is handling the 55's. I have them into the lands about .005/.006 and it seems to work.

View attachment 982796 View attachment 982796

Really interesting. Especially since you're not pushing max warp velocity.

 

[Dean Slater]

Really interesting. Especially since you're not pushing max warp velocity.

Just ordered a 7 twist per Berger's recommendation. Hope it's not to fast.

 

[Wirelessguy2005]

I know a couple guys running the 55's thru a 10 twist barrel with success. Personally I have ran them thru a 9 twist with no problem. Also ran the 50's thru an 11 twist with great accuracy, berger recommended an 8 twist for those. Needless to say Bergers recommendation is on the conservative side.

 

[GAnderson]

Really interesting. Especially since you're not pushing max warp velocity.

Yes, I tried stepping them up some but the groups started to open up, so this load seemed to be a sweet spot. It did the job on pdogs at the 970 yard mark. The 40gr BIB did excellent at that range also...was able to crank up the velocity on it, but still not at warp speed...sometimes all the extra stress on equipment and brass isn't worth it if they are accurate.

Gene

 

[jotrot]

I have a 204 ruger with a 9 twist and the 55 bergers love it if only they would make a 50gr. ballistic tip

 

[Tommie]

Another question:
How do the 55 grainers perform on prairie dogs? No doubt the bullets are accurate but do they show much terminal performance? I've read that they "pencil" through when ranges start to stretch out.