Some time last fall I decide on a Custom LR build. Skipping all of the build details for now, I ordered a New Shilen #6 Contour barrel for the build. Long story short, I was planning the 168 gr class of bullets when I did the order, then found the Berger 215's. when I ordered the barrel, I did it with a 1/12" twist. Am I in trouble? I have loaded some 215's and also a few 190 gr Bergers with H-1000. I have not been to the range yet with the new build. What can I expect? Any help or suggestions will be appreciated. Griz
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Did I go Wrong? Custom .300 Win Mag. 1/12" twist
- Thread starter dagrizman
- Start date
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gohring3006
Well-Known Member
Probably in trouble....... Check out the 200 hybrid it might stabilize....
Jerry M
Well-Known Member
300 WM will kill a lot with a 180-200 grain bullets. Range sessions will tell all...
Good luck
Jerry
Good luck
Jerry
This build will not be a hunting rifle. Started with a Weatherby MK V action, B&C A5 stock, 20 MOA Base, Huskemaw 5x20 LR Scope. 28" Shilen tube Barrel spiral flute and muzzel break by Kempfeld Customs. Weighs in about 15.5 lbs. I just need to get it to the range and see what I have to work with.
MagnumManiac
Well-Known Member
I think you may be in trouble with anything heavier/longer than 180gr VLD's.
I have a Hart with 1:13" twist, it WILL NOT stabilise anything above 168gr, even at 300WM velocities.
Cheers.
lightbulb
jjmp
Well-Known Member
Had a 1-12 twisting my old factory 308 varmint bbl she shot 190 Sierra MKings fine never shot any bergers,don't think she'll handle them b215s though, sorry jjmp
Unless you have serious velocity and altitude going for you, stabilizing the 215 in theory is quite the challenge. Check out >>> Twist Rate Stability Calculator | Berger Bullets.
If altitude is not in your favor, try the 185s. Good luck and happy safe shooting/hunting.
Ed
If altitude is not in your favor, try the 185s. Good luck and happy safe shooting/hunting.
Ed
Jokostel
Well-Known Member
About the only heavy weight you'll be stabilizing in that pipe is a Sierra 220 RN..
Should have been a 1-9.5 or a 1-10.
Should have been a 1-9.5 or a 1-10.
D
Deleted member 46119
Guest
If it's not too late, IIWM I would get a 10 or 9.5 twist.
Don't panic..... LOL
If it is already fitted, up to 190s should work fine at an easy 3000+fps.
1000 yards drift and drop are not excessive. Our current trend in heavy/long for caliber does not mean that what used to be considered heavy/long like 190s in 30 cal won't work. It will work just fine.
Don't panic..... LOL
If it is already fitted, up to 190s should work fine at an easy 3000+fps.
1000 yards drift and drop are not excessive. Our current trend in heavy/long for caliber does not mean that what used to be considered heavy/long like 190s in 30 cal won't work. It will work just fine.
I an just going have to do lot of testing. Where the big problem is going to be is that this was chambered for the 215's. I have lots of chamber to work with, just going to need to work up loads and seat the pills long as possible still being safe. I will keep the forum posted as to my progress. On a side note: can a barrel be re-bored to a larger dia. and change caliber. I have a ton of $ in this barrel. Griz
What, exactly, does that mean? What are your chamber specs?
Looking at the Berger spec sheet, I don't see any special needs for the 215 gr bullet. There are bullets listed for a 12 inch twist that have a longer bearing surface than the 215 gr has.
With a 215 Berger VLD, @ .003 of the lands, my OAL is at 3.686. Touching the lands it is 3.699. I set up my Forstner die getting the reading from my OAL gauge of the ogive. A 168 Hornaday A-Max is 3.516 .003 off the lands. Can I seat the 168 - 190 gr pills long as long as I have enough bearing surface for a good case bit on the bullet?
The bearing surface on the Berger 190 gr VLD is the same length as the 215 gr bullet.
The bearing surface on the 185 gr classic hunter is also the same length. The bearing surface on the 185 gr VLD is longer.
All three of those show to be suitable for a 12 inch twist.
The bearing surface on the 185 gr classic hunter is also the same length. The bearing surface on the 185 gr VLD is longer.
All three of those show to be suitable for a 12 inch twist.
gohring3006
Well-Known Member
There's is on a difference of about 2 moa between the 215 and the 185. You should be around 1100 ft lbs at 1000 with the 185 @ 3000fps.
