1:8" for 300WM: Is this too fast?

[Joefrazell]

the military shooting 220smks in a 300 win mag use a 1/10( 1500 YARDS plus)
my 1000 yard bench gun shooting 210s is a 1/10
there is no reason for a 1/8 NONE

The

the military shooting 220smks in a 300 win mag use a 1/10( 1500 YARDS plus)
my 1000 yard bench gun shooting 210s is a 1/10
there is no reason for a 1/8 NONE

The military is known for using tools that will work but that may or may not be the perfect tool for the job.

 

[Joefrazell]

So your gonna be shooting animals at a mile?

No Sherm, that would be irresponsible.

 

[shawnb]

sorry your thread got hyjacked, hopefully if you get the rifle you can post back about your shooting results.

 

[Joefrazell]

Please don't be concerned about a 8 twist in a 300 win mag unless your planning on shooting 150 gr. Projectiles. In that case I'd go to a different cartridge all together.

 

[Wolf76]

I'd take a 9 if heavies were part of the equation. But 10 handles everything I shoot. Think 8 is Overkill.

 

[reelhardmt]

I love speed so id be into a 1:10 3 groove at 28"

 

[WildRose]

I'd take a 9 if heavies were part of the equation. But 10 handles everything I shoot. Think 8 is Overkill.

It may be currently but 2-3 years from now when someone is making a 240gr mono and someone else is producing a 265gr conventional bullet people on this board will be going nuts to get a hold of them and many will be wishing they'd gone ahead with a 1:8 or 1:8.5 twist vs a 1:9 or 1:10.

Plan your build today for the bullets you'll be shooting tomorrow and it'll save you a lot of heartache and aggravation.

A couple of years ago I was horribly disappointed to find out that none of my STW's had enough twist to run a particular new prototype VLR 5 that Peregrine was producing so I had to drop back to the 150gr range after blowing two shots on an enormous boar at very reasonable ranges.

Went back to the range and found out some of them wouldn't even hit paper at 100yds.

I made the mistake of getting overly excited, loaded up enough for some experimenting, ran out to the range and fired 3 shots thinking I had a great zero.

Turns out I only hit one of the three and the bullet had gone through at a really weird angle apparently spinning sideways making it look like 3 shots in a single hole.

 

[milo-2]

Isn't Bartlien making some left hand gain twist barrels that are yielding some impressive results?
5-6 yrs ago I would never considered one, my next barrel I buy may be one.

 

[WildRose]

Isn't Bartlien making some left hand gain twist barrels that are yielding some impressive results?
5-6 yrs ago I would never considered one, my next barrel I buy may be one.

Gain twist barrels were all the rage a couple or three years ago but there are some real issues with them, namely they can tear bullets completely apart particularly at high velocities.

The gain twist will eat away much more of the outer surface of a bullet before it leaves the muzzle than a standard twist barrel will. This can seriously weaken bullets with a thin jacket.

 

[Wolf76]

It may be currently but 2-3 years from now when someone is making a 240gr mono and someone else is producing a 265gr conventional bullet people on this board will be going nuts to get a hold of them and many will be wishing they'd gone ahead with a 1:8 or 1:8.5 twist vs a 1:9 or 1:10.

Plan your build today for the bullets you'll be shooting tomorrow and it'll save you a lot of heartache and aggravation.

A couple of years ago I was horribly disappointed to find out that none of my STW's had enough twist to run a particular new prototype VLR 5 that Peregrine was producing so I had to drop back to the 150gr range after blowing two shots on an enormous boar at very reasonable ranges.

Went back to the range and found out some of them wouldn't even hit paper at 100yds.

I made the mistake of getting overly excited, loaded up enough for some experimenting, ran out to the range and fired 3 shots thinking I had a great zero.

Turns out I only hit one of the three and the bullet had gone through at a really weird angle apparently spinning sideways making it look like 3 shots in a single hole.

There MIGHT be an argument to be made for an 8 with a heavy mono.
But
A 300 W M doesn't have the case capacity for a cup core bullet beyond 230 grs. and keep up the speed. Even the 230 is sacrificing some velocity. IMO hunting bullets should shoot 2800+ fps and that isn't happening with the super heavies. And the heavy combination is far from optimal (just like a 200 GR bullet in a 308 is far from optimal). My 300 wm is my favorite gun and it's close to needing a new barrel. I'll get a 10 or a 9 because after a 215 Berger, you see the law of diminishing returns.
A 30 nosler or 300 rum is a different conversation.

 

[FEENIX]

There MIGHT be an argument to be made for an 8 with a heavy mono.
But
A 300 W M doesn't have the case capacity for a cup core bullet beyond 230 grs. and keep up the speed. Even the 230 is sacrificing some velocity. IMO hunting bullets should shoot 2800+ fps and that isn't happening with the super heavies. And the heavy combination is far from optimal (just like a 200 GR bullet in a 308 is far from optimal). My 300 wm is my favorite gun and it's close to needing a new barrel. I'll get a 10 or a 9 because after a 215 Berger, you see the law of diminishing returns.
A 30 nosler or 300 rum is a different conversation.

"Sometimes" it's not all about velocity. I know guys here that shoots the 215 Berger out of their .308/.30-06 (IIRC @MontanaMarine (?) and @bigngreen does) and @Broz with the 230 Berger with his .300 WM. Cheers!

 

[xsn10s]

1:10" (or faster) is the minimum twist for the 215 Berger (https://bergerbullets.com/product/30-caliber-215-grain-hybrid-target/). I have a 1:10" in my .300WSM and propelling the 215 Berger at 2800 FPS. At my range altitude, SG = 1.63 (1.5 or better ensures stability). If I go with ...
1:9": SG = 2.01
1:8" : SG = 2.25

So that should optimize the BC. Looks like the load would be fine at my altitude to around 800 yards.

 

[Wolf76]

"Sometimes" it's not all about velocity. I know guys here that shoots the 215 Berger out of their .308/.30-06 (IIRC @MontanaMarine (?) and @bigngreen does) and @Broz with the 230 Berger with his .300 WM. Cheers!

Completely agree. Its not all about velocity. IMO Optimal = the best combination of accuracy+energy+velocity. That's why there are nearly all factory rounds for the 308 are between 150-180 grs.
Since the question is regarding a factory Browning gun, I don't think people that have special throated +long barreled guns apply here.
There's a ton of appreciation for people that are willing and able to experiment with niche loads. Without this group, I'd be shooting a 200 gr accubond- not a 215 Berger.

 

[xsn10s]

"Sometimes" it's not all about velocity. I know guys here that shoots the 215 Berger out of their .308/.30-06 (IIRC @MontanaMarine (?) and @bigngreen does) and @Broz with the 230 Berger with his .300 WM. Cheers!

Yup those guys been doing some amazing things with the 215gr and 230gr Berger. I have the right powders, but not the Berger bullets to test. I may get some ELDM's in the mean time to test loads and velocities. I do have a gallon bag full of 190gr CC's, don't ask don't tell . I could play with those and Ramshot Hunter just for fun and to see what might be possible with 185gr-190gr weight class.