35 cal. twist ?

[piute]

I'm going to build a 35 Whelen, maybe make an AI.
I know from research that a 12/14 twist is standard go to but thinking about trying this barrel I can acquire with a fast 9.5 twist.
Would like to shoot 250Gr. bullets and probably will try to use Barnes 225Gr.TSX.
Anyone foresee any problems?

 

[Kurz]

Because of the weight and lengths of the available bullets you really do not need to spin them that fast. A standard 1:14" has more than enough spin to keep even the solids stable. Use the Berger stability calculator to get your answer.

ADDED:

Even the 280 grain Swift A-Frame is more than stable using the 1:14".

 

[sawcarver]

I use a 1-14 in a few 357 Max's using 150gr cutting edge solids. They work great, cutting edge shows their 180gr also work with 1-16

 

[Geno C]

My 358win is a 1-10 and is extremely accurate with 250 interlock bullets

 

[Rdlningcltchdmpr]

I'm going to build a 35 Whelen, maybe make an AI.
I know from research that a 12/14 twist is standard go to but thinking about trying this barrel I can acquire with a fast 9.5 twist.
Would like to shoot 250Gr. bullets and probably will try to use Barnes 225Gr.TSX.
Anyone foresee any problems?

Use the 180 ttsx , it is super accurate , less recoil and will go through any big game animal at any angle regardless of bones. It creates a bigger wound than the heavier ones.

 

[Ledd Slinger]

A 14 twist is all you will ever need even for very heavy hunting bullets. A 12 twist would be over twisting many bullets out there.

It is NOT good to over twist bullets unless you plan on shooting them past their transonic range. Even then, most people only over twist by an inch or two at best. 35 Whelen is not a great choice for long range work so I dont think you have to worry about ELR shooting.

Figure out the bullet you plan on using then twist the barrel at the exact rate required for that bullet. No more, no less.

 

[piute]

Thanks for the replies.
I get it about not needing a fast twist, just wondering if it will be detrimental or what problems there are using the 9.5 twist?
Someone mentioned about seeing higher pressures before reaching descent velocities. Again I will probably use 225 TSX so shouldn't have to worry about bullet construction.

I found an older thread on here just now. Thanks Guys for the info.

 

[Ledd Slinger]

Thanks for the replies.
I get it about not needing a fast twist, just wondering if it will be detrimental or what problems there are using the 9.5 twist?
Someone mentioned about seeing higher pressures before reaching descent velocities. Again I will probably use 225 TSX so shouldn't have to worry about bullet construction.

I found an older thread on here just now. Thanks Guys for the info.

You will never find the best accuracy possible using a faster 9.5 twist on a bullet that calls for a 14 or 12 twist. You will actually reduce accuracy.

I've over twisted a couple barrels, one in 6.5 and one in 30 cal. Was thinking it would help, but they never shot as good as barrels properly twisted for the exact requirement of the same bullets.

Most recently was a 30 cal where I decided to use a 1 in 8 when I only needed a 1 in 9. It shot 230gr nd 215gr Bergers pretty good, but wouldn't shoot 200s worth a damn. Now use 1 in 9 and accuracy has definitely improved across the board.

I know different barrels can have different levels of accuracy, but you wont find any top level competition shooters that recommend over twisting a barrel for any reason either.

 

[JohnW...ski]

About 35 years ago I built a .35 Whelen, I used a 14 twist McGowen barrel. Shooting only cast gas check bullets I was never really happy with the accuracy using 245 and 290 gr bullets. They would shoot groups of around 3" at 200 yds. which would be excellent for hunting but I felt there was more to be had. After some research, I had Mountain Molds make me a 255 gr. mold and worked up a load that will consistently shoot 1-3/4" at 200 yds. and well under 3" at 300 yds.

Here is a picture of the rifle.

John

 

[Ledd Slinger]

I shot the 225gr Nosler Partitions in my 358 Norma Mag for a handful of years before I changed the rifle to a different chambering. Rifle would shoot 5 shots in a 1.5" group at 300 yards. 1 in 12 twist.
The 225 Partition has one of the highest BCs of all the 35 cal hunting bullets so it works well out to about 600 or maybe even 700 yards. And I guarantee nothing in North America will survive a good impact from that bullet.

 

[bobinpa]

I shot the 225gr Nosler Partitions in my 358 Norma Mag for a handful of years before I changed the rifle to a different chambering. Rifle would shoot 5 shots in a 1.5" group at 300 yards. 1 in 14 twist.
The 225 Partition has one of the highest BCs of all the 35 cal hunting bullets so it works well out to about 600 or maybe even 700 yards. And I guarantee nothing in North America will survive a good impact from that bullet.

I've been planning to build a 358 Norma for a while now and it is time for me to order the barrel... with that being said, most of what I could gather, it seems like a 12 twist is very common and you are the first person I know to use a 14 twist. My question is do you feel or did you see any evidence that you were on the fringe of not fast enough? Did the barrel shoot different bullets well or just one bullet well? I was all set to order a 12 twist and now you have me second guessing.... What kind of velocity were you getting?

 

[Treerat-sniper]

I have a MGM 1:16 in .357 Max for my Encore. I've ran 150 gr HPs up to 200 grain Horny RN. Seemed to shoot everything well.

 

[Ledd Slinger]

I've been planning to build a 358 Norma for a while now and it is time for me to order the barrel... with that being said, most of what I could gather, it seems like a 12 twist is very common and you are the first person I know to use a 14 twist. My question is do you feel or did you see any evidence that you were on the fringe of not fast enough? Did the barrel shoot different bullets well or just one bullet well? I was all set to order a 12 twist and now you have me second guessing.... What kind of velocity were you getting?

I may be mistaken. Might have actually been a 12 twist. I have the barrel in the shop still. Will check it tomorrow to be sure.

Velocity was 3030 fps in a 26" barrel. I have a bunch if load data I developed using powders not listed anywhere if you're interested

 

[bobinpa]

I may be mistaken. Might have actually been a 12 twist. I have the barrel in the shop still. Will check it tomorrow to be sure.

Velocity was 3030 fps in a 26" barrel. I have a bunch if load data I developed using powders not listed anywhere if you're interested

Thanks. I would appreciate it. That's good velocity.

 

[Ledd Slinger]

Thanks. I would appreciate it. That's good velocity.

It is a 12 twist.

It will push the 225gr bullets even faster, but theres no good brass available with primer pockets that will hold up for more than 2 firings. At 3030 fps, I was getting good case life. I started making my cases from Winchester 300 Win Mag brass and it actually shot quite a bit better than the actual Norma brand brass

 

[bobinpa]

It is a 12 twist.

It will push the 225gr bullets even faster, but theres no good brass available with primer pockets that will hold up for more than 2 firings. At 3030 fps, I was getting good case life. I started making my cases from Winchester 300 Win Mag brass and it actually shot quite a bit better than the actual Norma brand brass

Thanks again. The 12 twist seems to be what others have used, so that makes sense. I have some 308 Norma Mag brass that I was going to neck up. It is all 20 - 25 years old so I guess I'll see how it does.