.20 Creedmoor?

[1lessdog]

It’s a 20

What are you getting for speed? And what gr are you shooting?

 

[Elnicko]

55gr Bergers somewhere between 4000-4100fps. Still working on it.

 

[7315br]

55gr Bergers somewhere between 4000-4100fps. Still working on it.

My $.02 worth. I built a .20/250 about five years ago with the intent of a 1000 yd Prairie Dog set-up. I wanted to slow the barrel twist down to hopefully get longer barrel life...soooo I went with a 1:10 twist. It shot extremely well...but very disappointing in barrel life. Throat was shot in a little over 400 rds. The Berger 55 gr .20 Cal bullet was also disappointing beyond 800 yds as it just began penciling at the longer distances. I killed a few PD's at a 1000 yds plus, but the bullet performance was dismal. I could get 4,000 fps out for the .20/250 with the 55 gr Berger...but that was pushing it. I found another accuracy node at 3,830 fps which was better.

Target picture is a group (on the left) out of the 10-twist .20/250. It would shoot...but didn't last. Your .20 Creedmoor should work for you as a coyote rifle...at least for a while. Group on the right is a very tired .20BR barrel group...lol! Best of luck of your project.

 

[Scooby-93]

My $.02 worth. I built a .20/250 about five years ago with the intent of a 1000 yd Prairie Dog set-up. I wanted to slow the barrel twist down to hopefully get longer barrel life...soooo I went with a 1:10 twist. It shot extremely well...but very disappointing in barrel life. Throat was shot in a little over 400 rds. The Berger 55 gr .20 Cal bullet was also disappointing beyond 800 yds as it just began penciling at the longer distances. I killed a few PD's at a 1000 yds plus, but the bullet performance was dismal. I could get 4,000 fps out for the .20/250 with the 55 gr Berger...but that was pushing it. I found another accuracy node at 3,830 fps which was better.

Target picture is a group (on the left) out of the 10-twist .20/250. It would shoot...but didn't last. Your .20 Creedmoor should work for you as a coyote rifle...at least for a while. Group on the right is a very tired .20BR barrel group...lol! Best of luck of your project.

What is your altitude with the 10twist 20-250?

 

[7315br]

What is your altitude with the 10twist 20-250?

I shot the 10-twist groups at 4500' altitude. I live fairly high up. In the field in Wyoming 5,000-7,000' altitude. Through the years I've tried 11-twist and 12-twist Bartlein or Kreiger bbls with the 55 gr Berger with not good results (big case 20's). The 9-twist is a different story. I've shot really decent groups as as low as 1,000' elevation with the .20 BR's.

 

[L.Sherm]

If I build another fire breathing 20 cal again it will be on a CM 9tw nitride barrel.
So far the CM pac- nor 3G-11 Nitride barrel for my 20VT is shooting really good compared to my SS 3G-11

 

[B23]

My $.02 worth. I built a .20/250 about five years ago with the intent of a 1000 yd Prairie Dog set-up. I wanted to slow the barrel twist down to hopefully get longer barrel life...soooo I went with a 1:10 twist. It shot extremely well...but very disappointing in barrel life. Throat was shot in a little over 400 rds. The Berger 55 gr .20 Cal bullet was also disappointing beyond 800 yds as it just began penciling at the longer distances. I killed a few PD's at a 1000 yds plus, but the bullet performance was dismal. I could get 4,000 fps out for the .20/250 with the 55 gr Berger...but that was pushing it. I found another accuracy node at 3,830 fps which was better.

Target picture is a group (on the left) out of the 10-twist .20/250. It would shoot...but didn't last. Your .20 Creedmoor should work for you as a coyote rifle...at least for a while. Group on the right is a very tired .20BR barrel group...lol! Best of luck of your project.

Do you think it's likely your dismal bullet performance, particularly at distance, had something to do with the fact you were using a slow 10tw for the Berger 55's which would result in much slower bullet RPM?

 

[7315br]

Do you think it's likely your dismal bullet performance, particularly at distance, had something to do with the fact you were using a slow 10tw for the Berger 55's which would result in much slower bullet RPM?

Good question. You and I have discussed these barrel twists several years back...mostly about bullet b.c. The 10-twist does work at the higher elevations...but the bullet b.c. won't be as good as say a 8-twist. Its been a while but my memory (not that great...lol!) is a bullet rpm of just under 300,000 rpm which is what I was trying to accomplish with the 10-twist and the .20/250. A lot of comments on this forum were made back then about the 55 gr Berger coming apart with a 8-twist and velocity above 3750. My experience was poor bullet performance beyond 800 yds with the 55 gr Berger, 10-twist, and the .20/250. The .20BR was about the same bullet performance with the 55 gr Berger beyond 700 yds. The .22-243 Imp solved that problem for me. If memory serves, I think you have a .22-243 Imp also.

After lotsa dollars trying several different large capacity .20 cals, I've become a .20PPC guy as the largest .20 cal. At least I can live with the barrel life of that one.