1-8 twist for 55 grain .20 cal Bergers?

[long40shot]

What about a 204 pushing the 55s? Any good?

 

[Woollybugger]

What about a 204 pushing the 55s? Any good?

Maybe in a single shot, 8 twist long Freebore. Tough to get them to fit in a mag with that bullet above the neck shoulder junction.
If I were building another gun for the 55 berger it would be a 20 ppc 20 grendel, 20 BR or 20 GT.

 

[long40shot]

Maybe in a single shot, 8 twist long Freebore. Tough to get them to fit in a mag with that bullet above the neck shoulder junction.
If I were building another gun for the 55 berger it would be a 20 ppc 20 grendel, 20 BR or 20 GT.

I've got a 6ppc that is probably gonna need a barrel at some point. I have decided that a 20ppc is the next project.

 

[Gabe22BR]

I've got a 6ppc that is probably gonna need a barrel at some point. I have decided that a 20ppc is the next project.

I got a 1-9 at the smith now- 20PPCAI - hope to get the 55 to 3300, maybe…. plan is use the 40BIB…3800

 

[Dstaffk5]

9 in my 20 br shoots bugholes

 

[lgwatson]

View attachment 16840981-9 Kreiger 600yd BR
This is the 2nd time it’s proved it’s self-
20BRAI

Nice shooting!

 

[lgwatson]

Those of you who are shooting the 55gr Bergers out of a 20 caliber cartridge, what twist rate is working for you? Berger recommends 1-7 or faster, that limits barrel manufacturers some what. Most offer a 1-8 but not all offer anything faster. Lilja and PacNor do 1-7s but…..

I want to use a Mueller for this build but 1-8 is his fastest twist.

This is for a 20GT build by the way.

Any input welcome.

I have a 20 Practical with a Lothar-Walther 9 twist. Shoots very tight with 55 Berger VBTs. Most of my shooting is 3400 feet and higher.

 

[searcher]

1-9 all the way. I had a conversation with the late Stan Taylor and he told me he tested a 8, 8.5 and 9 and the 9 was the best.
This is all the proof I need with my 9, this is out of a gun that is nothing special, untouched 700, Boyds Thumbhole stock and 14oz trigger and a barrel I made.

Good job on that barrel!!

 

[Evan]

I got a 1-9 at the smith now- 20PPCAI - hope to get the 55 to 3300, maybe…. plan is use the 40BIB…3800

How long a barrel? I would be shocked if you didn’t make it to 3300. My 20 Vartarg has a 26” barrel and goes 3150fps without damaging the brass. Your PPC will have about twice the capacity.

 

[L.Sherm]

H20 capacity in a 20PPCAI is about 11.5 gr more than the VT, I hit pressure around 3450fps in a 24" barrel with the 55's in my PPCAI

 

[Evan]

H20 capacity in a 20PPCAI is about 11.5 gr more than the VT, I hit pressure around 3450fps in a 24" barrel with the 55's in my PPCAI

I’m surprised! My vartarg uses 17gns of H4198 and my 22 PPC uses 28gns of Varget.

 

[effendude]

I can't find the 55's on Berger's site. New or old production?
Scott

 

[Evan]

I can't find the 55's on Berger's site. New or old production?
Scott

Grafs orders special runs of them. They were discontinued.

Edit: https://www.grafs.com/catalog/produ...pBLT7R9NbxP4qcnvQuvwGfG1AYc9survB_RxhwfKAMwT0

 

[L.Sherm]

I’m surprised! My vartarg uses 17gns of H4198 and my 22 PPC uses 28gns of Varget.

I think if you used similar burnrate powders the gap would close.

 

[L.Sherm]

I was about 27.6 of RL15 with the 55's was about max in my PPCAI after that is were I started seeing pressure. I was able to get a little more FPS with 15.5 before I saw pressure nothing in the accuracy dept. because all I have is an 11tw just trying to see what kind of speed I could get.
With the 39's i was just under 31.0 with AA2520.

 

[Evan]

I was about 27.6 of RL15 with the 55's was about max in my PPCAI after that is were I started seeing pressure. I was able to get a little more FPS with 15.5 before I saw pressure nothing in the accuracy dept. because all I have is an 11tw just trying to see what kind of speed I could get.
With the 39's i was just under 31.0 with AA2520.

Info like this reminds me how hot I am actually running my 20 Vartarg. The Lapua brass with a closely matched chamber and dies has held up great. My oldest set of brass has 10 reloads now. When I was pushing up to 3250fps with 20gns of Benchmark, that was noticeably hard on the brass. I thought for sure a 20 PPCAI would take 30gns of powder and maybe like an H4350 speed powder.

 

[L.Sherm]

I think the 4350 is to slow, I couldn't get any speed out of 4350 in my 20BRA with the 55's no matter how much I dumped in the case.

 

[Gabe22BR]

I think the 4350 is to slow, I couldn't get any speed out of 4350 in my 20BRA with the 55's no matter how much I dumped in the case.

You right, fill case full with a drop tube, crunch seat a bullet gonna get ya 3400 ish FPS….. then have unburnt powder in the barrel

 

[xswanted]

Those of you who are shooting the 55gr Bergers out of a 20 caliber cartridge, what twist rate is working for you? Berger recommends 1-7 or faster, that limits barrel manufacturers some what. Most offer a 1-8 but not all offer anything faster. Lilja and PacNor do 1-7s but…..

I want to use a Mueller for this build but 1-8 is his fastest twist.

This is for a 20GT build by the way.

Any input welcome.

I’ve ran them in a 20Br, 20-250 and a 204.

20Br and 20-250 were both 9 twists and would stabilize them fine at 850ft and all the way down into negative teens below zero.


The 204 was an 8 twist and worked very well with the lower speed.

I’d recommend the 9 with the bigger case.