What bullet were you shooting?
I have a 10twist bartline shooting the 40vmax at 4175fps with 747 rounds down it.
Throat is rough but still shooting sub .5moa
What 20 caliber ….
- Thread starter nakneker
- Start date
I have a 10twist bartline shooting the 40vmax at 4175fps with 747 rounds down it.
Throat is rough but still shooting sub .5moa
7315br
Silver $$ Contributor
Entirely with the Berger 55gr bullet. That's all I shoot in the the big case 20's. I ran it at 4000 fps for a while, then slowed it down to 3830 fps (very accurate) as the throat was starting to look like a "freight train going down a dirt road"...lol!
I initially was only looking for about 600-700 rds anyway. I'll keep them around (for a while at .3" groups)...but I'm always looking for .2" groups or better.
Sincerely hope yours keeps going for you.
Attachments
Last edited:
nakneker
Gold $$ Contributor
I wanted to use a proof barrel for the 20GT build. I will be shooting 55 grain Bergers for the build but the only 20 caliber they list on their website is a 22” barrel with a 1-10 twist. I’d be ok with the length but I’m thinking 1-10 may or may not stabilize the 55 grain Bergers? The test target above shows a good group with a 1-10 twist that 7315br posted.
What your experience with twist rates in 20 caliber shooting the 55 grain Berger? I’m not set on a Proof but would like to use it if it works. I’ve had really good luck with Mueller 20 caliber barrel in my 20PPC also.
What your experience with twist rates in 20 caliber shooting the 55 grain Berger? I’m not set on a Proof but would like to use it if it works. I’ve had really good luck with Mueller 20 caliber barrel in my 20PPC also.
Last edited:
Fern
Silver $$ Contributor
When I bought my 20 tac the gentlemen gave me a second faster twist barrel (think 8) that he used when he shot the 55s
My 20 Vartarg wears a 9twist Hart, but I’ve not tried it below 5000ft elevation.
7315br
Silver $$ Contributor
That has been an issue for me with the 10-twist and the .20/250. Mine shot well at 4500' elevation and up. I shot it on PD's up to 7,000' elevation and over 1000 yds.
My go to twist for the 20BR has always been a 9-twist. They shot well with the 55 gr Bergers even at a 1000' elevation.
Unfortunately the 8-twist bbls "can" cause bullets coming apart after about 300 rds on the big case .20's driving them above 3750 fps. Some bbls handle it...some don't.
Best of luck on your decision.
Last edited:
7315br
Silver $$ Contributor
Kreiger or Bartlein would be my choice as I like the single point rifling they provide. Their twist rates have always been on the money in my experience.
Last edited:
B23
Gold $$ Contributor
I talked to Berger extensively about twist for their 55's when I was having my 20-250 built and what they told me was they know of shooters using 9tw and even 10tw barrels to shoot their 55's getting success in the accuracy department, but, anything slower then an 8tw and I would not be getting the full BC of that bullet so I had my 20-250 built using a Krieger 8tw. I actually ordered two 8tw 20 cal barrels from Krieger so I'd have a spare ready to go and not have to wait 9+ months getting another barrel.
nakneker, if you don't want to wait I still have that extra Krieger 20 cal 8tw sitting on the shelf that I'd sell. It's a Sendero contour and was fluted by Krieger.
nakneker, if you don't want to wait I still have that extra Krieger 20 cal 8tw sitting on the shelf that I'd sell. It's a Sendero contour and was fluted by Krieger.
I have one of Stan’s 1-9” twist barrels. He was 100% correct. Works superbly in a large case cartridge with 55 Bergers.
Would you mind sharing details on your 20 dasher?
GT Accuracy
Site $$ Sponsor
Borden BRM
Kreiger Barrel - 11 Twist - 26"
GTA Lowrider Stock
Bix Trigger
39 or 40 gr bullets
If you're looking for more powder, primer, bullet info with some notes, give me a little bit, I'll have a compendium ready in july some time. The following calilbers all specialized with varmint loads as competitoin loads are more readily available:
- 20 Vartarg
- BR Family
- 20 BR
- 22 BR
- 6mm BR
- BRA Family
- 20 BRA
- 22 BRA
- 6mm BRA
- Dasher Family
- 20 Dasher
- 22 Dasher
- 6mm Dasher
- 22-250 Family
- 22-250
- 22-250 AI
- 6-6.5x55 Swede
- More readily available 6mm AI replacement
- 6mm AI
- Necked down from 8x57 Lapua Brass
- 6-6.5 PRC
- 6-6.5 PRC AI
- 300 WSM Varminter
Last edited:
I look forward to reading that, what velocity were you getting out of the 20 dasher with the 39 & 40gr bullets
GT Accuracy
Site $$ Sponsor
I'll post the google sheet link here when I actually get some data in it. I am including all quickload PSI pressures and QL velocities in columns before my shot averages in another column
I’m going to be a lot slower than that I would guess, 20” barrel 11twist - hopefully still make 4000fps
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.