1 in 7.5 Twist 257 Weatherby

[flyinstroke]

I was blowing primers with Federal Brass. I have changed over to Laupua brass and slowly working back up. Don't have enough supplies to play around too much. I stuck with the node's I know. Once I get restocked I will try again and see what happens.

 

[GLTaylor]

Berger Bullet's has a stability analysis calculator to determine twist rates. Just how good this is I don't really know, but I don't think they would put something out that incorrect either. It could be only for their bullets too. I've been looking at twist rates for a 6mm AI or along that line of thinking. The only different is I am looking at 105 grs to 115 gr bullets to shoot only. Bartlein builds barrels with twist rates that start out in the chamber at one rate and continues to increase as it reaches the muzzle. In my mind that see to work out, by lowering the chamber pressure at the start by not having a high rate of twist to start with. Achieving the twist rate at the muzzle or withing a few inches of the muzzle. I am looking at a rifle to shot out to 700yds, and not for elk either. Achieving velocity or about 3200 fps at muzzle with at 1-7 twist. Looking for input.

My 25-284 does 3300 with Blackjacks and Superformance no problem. 7:5 twist Bartlein from BJ.

 

[willfrye027]

My 25-284 does 3300 with Blackjacks and Superformance no problem. 7:5 twist Bartlein from BJ.

Wow! I hope to get close to that with my 25-06. I'll have to try superformance..been stocking up on slower burning stuff to try.

 

[Mike Matteson]

My 25-284 does 3300 with Blackjacks and Superformance no problem. 7:5 twist Bartlein from BJ.

Your Bartlein barrel is it continues 7.5 twist or does the twist speed up toward the muzzle end.? Because I am looking very hard at a Bartlein barrel for a 6mm build. I have in mind the case I am going to use with the 6mm caliber, and the grain of bullets which is limited to 105gr to 115gr bullets. I have other rifle to shot lighter bullets.

 

[GLTaylor]

Your Bartlein barrel is it continues 7.5 twist or does the twist speed up toward the muzzle end.? Because I am looking very hard at a Bartlein barrel for a 6mm build. I have in mind the case I am going to use with the 6mm caliber, and

Your Bartlein barrel is it continues 7.5 twist or does the twist speed up toward the muzzle end.? Because I am looking very hard at a Bartlein barrel for a 6mm build. I have in mind the case I am going to use with the 6mm caliber, and the grain of bullets which is limited to 105gr to 115gr bullets. I have other rifle to shot lighter bullets.

My barrel is straight twist 1:8, not a gain twist - which is what you're describing.

 

[GLTaylor]

Wow! I hope to get close to that with my 25-06. I'll have to try superformance..been stocking up on slower burning stuff to try.

I rechecked my memory. Speed was 3228 wirlth Superformance and 131 BJs. My cartridge length is 3.382. Sorry. My goof.

 

[Mike Matteson]

Know anybody that has used or using a gain twist barrel? Or anybody that's reading this used a gain twist barrel? I haven't used any barrel that are faster than 9-1. I hold my shots under 500 yds for game. Looking at doing some 700 yd work on dogs, nothing in the 1000 area.

 

[GLTaylor]

You certainly do not have to have a gain twist barrel to shoot long, aerodynamic bullets to great distances. Standard twist barrels work just fine. Just be sure to get a twist rate that will stabilize the bullet weight and type you want to shoot.

Berger has a twist rate/stability tool free for use to tell you what twist rate you need for a given bullet. If you select Hammer Bullets, read the description for each bullet. It will tell you what twist barrel the bullet needs to stabilize.

 

[Mike Matteson]

You certainly do not have to have a gain twist barrel to shoot long, aerodynamic bullets to great distances. Standard twist barrels work just fine. Just be sure to get a twist rate that will stabilize the bullet weight and type you want to shoot.

Berger has a twist rate/stability tool free for use to tell you what twist rate you need for a given bullet. If you select Hammer Bullets, read the description for each bullet. It will tell you what twist barrel the bullet needs to stabilize.

First I want to thank you for the info on Hammer Bullets. I haven't use them yet, but been reading about them some and now I will look into them.
I was looking at a gain twist barrel is to reduce the chamber pressure at the start, but at the muzzle have the twist rate needed or require. Bartlein builds a gain twist barrel. Has anybody used a gain twist barrel, and did they like it or had problems stabilizing the bullets being used with build? It's an option I am looking at. I am close to putting hard money on the table. I have chamber configuration where to get, dies, reamer, action, barrel manufacture & twist rate, length, stock, scope, trigger. Just haven't settled on standard twist rate or gain twist rate barrel yet. Looking for people that have use gain twist barrel, and there comments about them before I go to the manufacture of the barrels and talk to them.

 

[Hoss50]

I built my 257 weatherby with a 1:8 twist barrel. I am still in the load development stages with the 131gr blackjack bullets. I have seen some groups that are extremely accurate and some that are just ok. I am going to try some more work with H1000, but I also have some loads to test with RL26 which is what blackjack told me they are running in there 257 weatherby.

Harley

 

[Mike Matteson]

I am looking to have a 6mm-06 built, and using 105 to 115 grain bullets. I started look at hammer bullets, but they don't built 6mm in those weight of bullets. I think they are on the right track. Hopefully they build some heaver grains bullets for the 6mm. I going to take a look at the blackjacks too. Thanks for the input.

 

[shinbone]

On gain-twists barrels - note that gain-twist barrels have been around for many decades. Knowing how competitive shooters are always looking for an extra "edge", and how hardcore hand loaders are always pushing the envelope, if gain-twist offered some notable improvement over a straight-twist barrel, they would be all the rage. They are not, and so they don't.

You want to shoot 100gn - 131gn bullets in your new .25 cal rifle? - get it twisted for 131gn, and then, shoot mono's if the lighter cup-n-core bullets blowup on you.

JMHO

 

[GLTaylor]

^^^^
This.
Twist 1:7.5 is preferred for the Black Jacks. That or faster (7) for big monos

 

[GLTaylor]

I built my 257 weatherby with a 1:8 twist barrel. I am still in the load development stages with the 131gr blackjack bullets. I have seen some groups that are extremely accurate and some that are just ok. I am going to try some more work with H1000, but I also have some loads to test with RL26 which is what blackjack told me they are running in there 257 weatherby.

Harley

Your 1:8 twist might not be good for the BJs. They recommend 1:7.5. 1;8 may only be marginally stable