Questions on the 20x47 Lapua

[PAshooter20BR]

I had 20 BR years ago and have decided that it's time for another 20 cal. I am thinking that the 55 gr Berger is the way to go. If anyone shooting the 20x47 lapua can answer it may help me make up my mind.
1) is a 9 twist barrel the best way to go for 55 gr bergers?
2) what velocity would I expect with a 26 in tube?
3) anyone feeding these through a 700 BDL magazine?
4) comments on barrel life, anyone have real round counts?
5) if your shooting this caliber would you recommend anything else based on your experience? 20BR, 20-250 etc.
6) what are you using for dies?

Thanks in advance.

 

[TAJ45]

It seems like this was visited recently here but having several .20s, my reading has been an 8 is needed for the Berger 55s. Berger even says so. I have a 20 prac and a 20BR.

If you noodle around this site a bit more, I'm sure you'll find a lot of guys with a ton of first hand experience across the spectrum. Even some who say they can stabilize in 9". It does seem like I read that the BR case was actually overbore so you'll really be beyond with the 47L case. Depends on your use. I think Dave Affleck (sp?) is running a 20/250 for coyotes. It will be almost a lifetime, even with him, before he "shoots it out." He knows he is very much o'bore iirc.

Same with the 12" and 11" for the 39/40s. 11" all the way as you may/may not get a true 12 when you'll need every bit of it. I can't help you on velocities. Fast bbls, slow bbls and some just don't giveadarn..... ;-)) Like I say, noodle around here and search function the .20s and proceed to smile with all the good info you'll read.

 

[PAshooter20BR]

Thank you for taking the time to reply. I did spend a few hours yesterday searching the site for 20x47 posts and I compiled my list of questions based on things I could not find answers for. I am curious on the twist rate, I have read that 204 ruger will marginally stabilize the 55gr with a 9 twist, but also read a report that someone with an 8 twist 20x47 experienced bullet blow up with the 8 twist and needed a 9. My thoughts are the 20x47 with increased velocity will stabilize the 55 gr in a 9 twist but was hoping folks with a 20x47 could confirm.

 

[PAshooter20BR]

All,
I spoke with Todd kindler at the woodchuck den. He answered all my questions I had plus more. this guy is full of knowledge and passion about 20 calibers. They have a nice variety of stuff they sell too. Also he has copies of his 20 caliber reloading manual he wrote. Sounds pretty interesting. I will let you know when I get done reading mine. www.Woodchuckden.com
Check him out.

Thanks
Brandon

 

[rickiesrevenge]

What did he say? 9 twist?

Aaron

 

[stansrifles]

If you are going to run 3600 an under 8 twist is fine if you run 3650 plus you will need a 9 twist because of bullet failure.
Stan

 

[fredo]

Big .20 cals can be awesome ballistic performers, there's not doubt about that!
As with most any small caliber overbore cartridge, the limiting factor becomes bullet integrity. BCs and chrono #s look phenomenal on paper, but one must factor in RPM and it's effect on bullet jackets. Real world results can be somewhat sobering when bullets poof mid flight, or perform erratically on critters. The law of diminishing returns is increasing evident with reduced bore size...

http://www.rmvh.com/20-250%20-%20Bullet%20Selection.htm

Dave has 'been there & done that' with a whole crapload of bullet/cartridge combos, his words are well worth the read...

PS have a couple friend's who run .204AIs and they're getting wonderful performance with mid-weight bullets. One in particular is launching a 38Unmussig @ 4150. Tough bullet that will stay together @ warp speed & flat throttle a coyote to the dirt...

 

[thekriebles]

If you are going to run 3600 an under 8 twist is fine if you run 3650 plus you will need a 9 twist because of bullet failure.
Stan

Stan speaks from personal experience and he is a knowledgeable shooter!

 

[germanlongbow]

Im not sure how case capacity compares between 20x47 and the 20-250. I shoot a pacnor 1x9 28 inch tube with Berger 55's, Federal 210 M, Nosler brass(not my first choice but couldn't find lapua at the time) and H4350. It is a consistent sub 0.1 MOA rifle at 100 yards. Velocity is 3860 fps. The bullets are holding together without issue. Prior to this a was shooting a 20BR in a 1x8 twist Mullerworks barrel. Similar combo: Lapua brass, Fed 210M, 55 berger, and Varget. I gave up after 800 rounds of testing. Some sub 0.2 one day same load 1 moa the next. No consistency. As well the bullet was diffiicult to stabilize. I abandoned when I ended with a baffle strike on my suppressor. End of story. The 1x9 is perfect for the 55 gr Bergers. I sold the 20 BR to my nephew. He shoots the 40 gr Vmax with Varget. Velocity is 3990-4000 fps. Shoots in sub 0.1MOA all day. The Vmax are tough little bullets despite the 1x8 fast twist. Scott

 

[nakneker]

Big .20 cals can be awesome ballistic performers, there's not doubt about that!
As with most any small caliber overbore cartridge, the limiting factor becomes bullet integrity. BCs and chrono #s look phenomenal on paper, but one must factor in RPM and it's effect on bullet jackets. Real world results can be somewhat sobering when bullets poof mid flight, or perform erratically on critters. The law of diminishing returns is increasing evident with reduced bore size...

http://www.rmvh.com/20-250 - Bullet Selection.htm

Dave has 'been there & done that' with a whole crapload of bullet/cartridge combos, his words are well worth the read...

PS have a couple friend's who run .204AIs and they're getting wonderful performance with mid-weight bullets. One in particular is launching a 38Unmussig @ 4150. Tough bullet that will stay together @ warp speed & flat throttle a coyote to the dirt...

Interesting read. I like reading first hand experiences, in depth analysis. I have a 20 beggs on Sako 75 that loves decking coyotes. It shoots 39ers with great result. I've been toying with a 20x47, I'll research more, but Dave's article/experience may steer me another way.

 

[PAshooter20BR]

I have since competed my 20x47. As with any of the cases based off the 6.5x47 case I have experimented with I have had fantastic results in the accuracy department. Took me about 25 rounds to dial the load in with new brass shooting two groups at 300 under 1 inch before settling on the load for now. I used a bartlien 9 twist barrel. 55 grain bergers with H4350. I have about 50 rounds through the gun at this point. 16 groundhog kills ranging from 50 to 304 yards. Bergers have performed flawless, exits have been dramatic. I am feeding the rounds through a hs precision detachable magazine with no issues. If anyone ever needs any specific info send me a PM I can help you with whatever you need.
I am 100% satisfied with the 20x47. It's not for everyone, but if you like the 47 case, enjoy high velocity rounds, you won't regret it one bit.
Brandon

 

[Savageseven]

I have since competed my 20x47. As with any of the cases based off the 6.5x47 case I have experimented with I have had fantastic results in the accuracy department. Took me about 25 rounds to dial the load in with new brass shooting two groups at 300 under 1 inch before settling on the load for now. I used a bartlien 9 twist barrel. 55 grain bergers with H4350. I have about 50 rounds through the gun at this point. 16 groundhog kills ranging from 50 to 304 yards. Bergers have performed flawless, exits have been dramatic. I am feeding the rounds through a hs precision detachable magazine with no issues. If anyone ever needs any specific info send me a PM I can help you with whatever you need.
I am 100% satisfied with the 20x47. It's not for everyone, but if you like the 47 case, enjoy high velocity rounds, you won't regret it one bit.
Brandon

did you have to neck turn brass ??

 

[boltfluter]

did you have to neck turn brass ??

You may not get a reply as this was 9 years ago.

 

[L.Sherm]

He does still frequent here but any reamer can be set up for a specific brass so you dont have to turn.
Just about all Lapua BR, Grendel etc that has been necked down to a 20 cal needs a .236 for no turn.
All is around .232 loaded.