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View Full Version : What twist rate for custom 700 30-06 Mtn rifle and cast boolits!



1longshot
12-15-2014, 05:08 PM
I am going to put a new barrel on a stainless 700 mountain rifle I picked up cheap. I would like to put a mountain profile weight barrel back on it. Not having shot much cast in rifles, what twist do you recommend? Barrel length? Bullet weight/profile? I know the bullet will be the determining factor, however I think the classic 1-10 twist is too fast.

Thanks in advance.

W.R.Buchanan
12-15-2014, 05:56 PM
Are you only going to shoot cast boolits in that gun? Forever? 1:10 is just fine and would yield good accuracy with Jacketed bullets as well and 1:10 will work just fine for cast boolits too.

Others may chime in with alternatives, however virtually all .30 cal rifles are made with 1:10 twist barrels to begin with.

I wonder why?

I'm also big on 24" barrels. but that is just me. I like short ones like 16-18" too.

I don't really like 22" barrels, but I don't know why. Seems like an odd size to me and doesn't divide into "feet" very well.

Randy

RickinTN
12-15-2014, 06:21 PM
I'm shooting cast in several 30-06 rifles and they work pretty well. All of mine are 1-10" twist. The 30-06 is a good cast cartridge. If I could change one thing on mine it would be to twist them 1-12". It would be a little easier to get good accuracy and a little more velocity from the 1-12".
Rick

1longshot
12-15-2014, 11:59 PM
I was thinking a 1 in 12 as well. I don't plan on shooting any j-words over 165 any how.

Lonegun1894
12-16-2014, 05:05 AM
I was thinking 1:12" or maybe even 1:14" if this is going to be a dedicated CB rifle. I want to build one like that, but until I get the money together and do it to test it myself, I'd hate to spend your money when I haven't spent mine on this experiment yet.

Blammer
12-16-2014, 05:15 PM
I would try a 12T, for 30-06

rintinglen
01-06-2015, 02:24 PM
I was thinking 1:12" or maybe even 1:14" if this is going to be a dedicated CB rifle. I want to build one like that, but until I get the money together and do it to test it myself, I'd hate to spend your money when I haven't spent mine on this experiment yet.

1-12 or even slower will more likely lead to boolit bliss. I've toyed with the Idea of getting a 1-14 twist barrel for my gun.

RobS
01-06-2015, 02:44 PM
1:12" twist is a good twist for both jacketed and cast and like rintinglen I've thought about a 1:14 twist for a dedicated cast boolit shooting 375 H&H barrel. Problem is it will cost $300-$400 for a 1:14" custom barrel so I'll likely stay with the factory 1:12" barrel I have since $$$ never seems to be on the up and up. I can't complain though this Savage factory barreled rifle is a shooter with my 270 grain boolits.

colonelsanders
01-10-2015, 09:43 PM
I choose a 1-11 for my mountain rifle with a mcgowen octagonal no 1 profile.
The action is a square bridge doumolin from sarco. I have two actions so as soon as the funds for second barrel are approved i will put together a brace of identical rifles.
126962

kycrawler
12-28-2016, 12:52 AM
How about having your barrel rebored to 338-06 or 35 whelen ?I have 2 that Jes rebored and they shoot great

Scharfschuetze
01-05-2017, 12:30 AM
I wonder why?

WR,

You probably already know this, but that goes back to the Ordnance Department and their choice of the 220 grain FMJRN bullet in the original 30/03 which they adapted from the 30/40 Krag round. When they were playing catch up with the German spitzer bullets, they adopted the 30/06 with a 150 grain FMJ Spitzer. Instead of throwing out thousands of 1 in 10" twist 30/03 barrels optimized for the 220 grain bullet at about 2,200 fps, they just cut a thread off of the barrel shank and rechambered for the 30/06 with its shorter neck and lighter bullet. You are right, it worked just fine, but there was testing that showed a slower twist was actually more accurate with the new 30/06 ball round. At any rate, the 1 in 10" twist for the Ought Six has been with us ever since, even in most commercial rifles.

When the 7.62 NATO was adopted, its 148 grain FMJ Spitzer did just fine with a 1 in 12" twist and it fact; the 1 in 12" twist does just fine with much heavier bullets in the 308/7.62 NATO.


I've toyed with the Idea of getting a 1-14 twist barrel for my gun.

Now for a purpose made cast bullet barrel? The OP would do well with a 1 in 14." For high velocity cast bullet loads a 1 in 16" twist is superb. I have shot such barrels, both twist rates, to 300 yards with cast bullets at jacketed bullet velocities with almost MOA accuracy and no leading. A 1 in 12" barrel would be a good compromise for all weights of normally shot jacketed or cast bullets.

When I shot Palma matches in the 80s, the 7.62 NATO (308) cartridge was required and the heaviest bullet allowed was a 155 grain. The specialized Palma rifles with 1 in 14" barrels kept the the Sierra Palma bullet stable all the way to 1,000 yards with exceptional accuracy.