20Dasher, 20x47 Lapua or other for long range varmint

[ratbuster]

Having been impressed with Adam Bentley's 22 Dasher "Hog Exploder" http://forum.accurateshooter.com/threads/the-new-hog-exploder.3906084/ I am keen on doing something similar but with the 55gn 20 caliber Berger bullet. The .354 BC Berger is impressive and at expected 3900 fps would provide a far flatter trajectory than a 6 mm Dasher shooting the 105 gn Amax while providing very similiar wind drift performance. Of course the 55 gn Berger will have much less recoil too.

So my question is which cartridge to choose? I am thinking about the other 6BR improved cases, 20x47Lapua and 20/250. It will primarily be used for long range squirrels (low volume) and maybe some casual F class use but I imagine any amount of F class activity would burn out the barrel pretty quick. I know each cartridge has some advantages and disadvantages; they all will meet the basic need of getting to that 3900 fps goal so my primary concern is accuracy and brass life. Am I correct in thinking the BR cases would likely be more accurate than the longer 47 Lapua and 22/250 cases? Ease of forming brass and the associated cost of dies, etc. is a factor but I am willing to spend the extra time and money to have an edge in accuracy.

Thanks for your thoughts on this project.

 

[Phil]

I constantly toss this around, the 20 Dasher, 20 BRDX, and now, the 20 BR AI are three that I think about all the time......

All would be fun with the Berger 55gr. bullet.......

 

[22DASHER]

A 47 case is too big. 20 BR would be the max I would do.

Check out this article:

http://www.accurateshooter.com/guns-of-week/gunweek0103/

 

[Cool Tool]

Having been impressed with Adam Bentley's 22 Dasher "Hog Exploder" http://forum.accurateshooter.com/threads/the-new-hog-exploder.3906084/ I am keen on doing something similar but with the 55gn 20 caliber Berger bullet. The .354 BC Berger is impressive and at expected 3900 fps would provide a far flatter trajectory than a 6 mm Dasher shooting the 105 gn Amax while providing very similiar wind drift performance. Of course the 55 gn Berger will have much less recoil too.

So my question is which cartridge to choose? I am thinking about the other 6BR improved cases, 20x47Lapua and 20/250. It will primarily be used for long range squirrels (low volume) and maybe some casual F class use but I imagine any amount of F class activity would burn out the barrel pretty quick. I know each cartridge has some advantages and disadvantages; they all will meet the basic need of getting to that 3900 fps goal so my primary concern is accuracy and brass life. Am I correct in thinking the BR cases would likely be more accurate than the longer 47 Lapua and 22/250 cases? Ease of forming brass and the associated cost of dies, etc. is a factor but I am willing to spend the extra time and money to have an edge in accuracy.

Thanks for your thoughts on this project.

I think if you would really like some real data pm me I can give you some good data on the 20 dasher where the accuracy nodes are.

 

[40xmike]

I started shooting a .20 BR with the 55 grain Bergers last year. We've since killed a truck load of rock chucks with it. Longest kill so far has been 843 yards. We have also shot it on steel out to 1k. The 55 gr. Berger does surprisingly well at long range for a .20
This has been out of an XP-100 pistol with a 18" 1-8 twist barrel. Muzzle velocity is 3250 fps.
I've been also kicking around the idea of a .20 Dasher ;-}

-mike

 

[Phil]

A .20-223AI would do a fine job with the 55`s also......

 

[22DASHER]

Not mine but a pic for you to drool over...

I am pretty sure someone mislabeled the one on the right. It looks like a 20 BR AI




20 Dasher on far right:

 

[Cool Tool]

BY the way anything bigger than a 20 br you will need a 9twist.

 

[Phil]

Definately NOT a Dasher case on the right.......

 

[Cool Tool]

Definately NOT a Dasher case on the right.......

I cant tell 100% but the neck on the top pic looks a little to long.

 

[Phil]

I cant tell 100% but the neck on the top pic looks a little to long.

The top picture is the one i was referring to.

The bottom one is correct.

 

[Cool Tool]

I will take a pic of my 20dasher an post it beside a 6br an a 20 br comet tomorrow.

 

[22DASHER]

Re-read the post. Top pic has a 20 BR and a 20 BR 40 degree. Someone mislabeled that right one.

In the second pic the far right one is the 20 Dasher

 

[ratbuster]

22 Dasher:

Is a 20 BR 40 degree the improved BR? Clearly less case capacity than the Dasher.

I just ordered 1000 Berger 55's. BTW, a tech at Berger told me today said bullet is a good seller, growing in popularity and do not anticipate discontinuing it.

 

[Cool Tool]

Happy Thanksgiving bless you all here is some pics of 20 br 20br comet an 20 dasher an a 1000yd target I am not saying it is a benchrest cartridge but they hold there own.

 

[AckleymanII]

I have heard reports that the 55g Bergers may splash on coyote shoulders, anyone have any input. This report was by a guy shooting a 20/250 AI....unreal accurate.

 

[Cool Tool]

I have heard reports that the 55g Bergers may splash on coyote shoulders, anyone have any input. This report was by a guy shooting a 20/250 AI....unreal accurate.

I have had customers tell me they had to slow it down a tad to have good expansion hope this helps.

 

[fastnflat1]

I've got a 20BR, 2- 20 dashers and now a 20x47lapua. I always figured the x47 would be a bit over bore as well as the 20-250. I had about 500 50gr bergers that I wanted to utilize as yote bombers lol. After reading all that I could find and tossing the idea of a 20x47 or 20-250 around I finally went with the 20x47L. Reasons.... great brass with small primer pockets, a near straight wall case to increase powder capacity in the shorter body length, a sharper shoulder angle to help reduce trimming frequency and best I could tell from my reading it would do basically the same as the 20-250.

I chose an X-caliber 3 groove 9twist bbl and ordered a 20x47L finish reamer from PTG and went at it. No regrets so far!! With a tank full of H4350, Im running the 50gr berger right at 4000fps and with a 250yd zero it makes critter gittin the easiest I've ever seen.

I wouldnt recommend the 20x47L as a prairie dog round unless you had a death wish on your barrel or maybe wanted something small caliber, low recoil, to occasionally reach out and smack those beyond 500yds.

I must ad the X-caliber 3 groove bbl broke in nicely with very little shooting and cleaning. And it allows more velocity than I had anticipated. I have another waiting in the corner and am going to order a couple more some day soon.

Yes, the lapua brass is more costly than most other 22-250 brass and it requires more work to neck it down to the 20cal but all in all I'm thoroughly satisfied with the 20x47L.

I'm sure someday curiosity will get me and I will build a 20-250AI but before that I must build a 20VT as its been on my wish list for several years but I've always found other cartridges to build instead lol.

Happy building and shooting to ya!!!

 

[22DASHER]

Happy Thanksgiving bless you all here is some pics of 20 br 20br comet an 20 dasher an a 1000yd target I am not saying it is a benchrest cartridge but they hold there own.

George sweet rifles. We need more info and pics of those rifles, loads, etc!

 

[Cool Tool]

George sweet rifles. We need more info and pics of those rifles, loads, etc!

Well we found that H4350 was less temperature sensitive in the dasher an 20 comet its accuracy at 3750ish, at higher velocity it was not as good R-15 was very good as long as you stay 3750fps definitely long range varmit calibers up to about 600yds the 20br is a good cartridge an you can use a 8twist, I have lost bullets above 3650 that's why I went to a 9 twist sorry my keyboard ability sucks.
PS what post was the poster showing some hand pulled bullets someone makes they were a ballistic tip in 55gr.