7WSM Barrel twist

[Blkz06]

Yep another barrel twist question.

I'm in the process of building a 7WSM. I prefer Bartlein, and will be going with a 3B profile.

I have read recommendations from 1-10 to 1-8. Looking at barrels that are available, I see most are 1-8, 1-8.5, and 1-9.

Bartlein has a 1-8.7 that would seem to fit the bill, as I'm looking to use 168-180's as the norm for this particular rifle.

However, does that kill me if I want to go with 140's?

Any other negatives to going with a 8.7 twist?

 

[J E Custom]

Yep another barrel twist question.

I'm in the process of building a 7WSM. I prefer Bartlein, and will be going with a 3B profile.

I have read recommendations from 1-10 to 1-8. Looking at barrels that are available, I see most are 1-8, 1-8.5, and 1-9.

Bartlein has a 1-8.7 that would seem to fit the bill, as I'm looking to use 168-180's as the norm for this particular rifle.

However, does that kill me if I want to go with 140's?

Any other negatives to going with a 8.7 twist?

The 1 in 9 is preferred, but the 1 in 8.7 should work ok. The 7 WSM is very close to the 7 rem mag in velocity and the 168s work great with a 1 in 9.

J E CUSTOM

 

[Edd]

Based on the current bullet trend and the powder capacity of a 7mm WSM, I would use an 8" twist.

 

[Blkz06]

Based on the current bullet trend and the powder capacity of a 7mm WSM, I would use an 8" twist.

Can you elaborate further?

Big difference in the 2 recommendations.

 

[Edd]

Can you elaborate further?

There are some copper bullets in the 150-170 gr range that will like an 8" twist. Some of the heavy lead bullets will to. There are some situations where the 180 gr Berger shows to need an 8" twist.

A 7mm WSM has the powder capacity to use whatever bullet you want to use. I would put a barrel on there that would accommodate your choice. You can still use the lighter bullets if you choose.

 

[B23]

I recently had a 7mm Blaser Mag built and even though a 1-9tw would have easily been adequate for the currently available 180's the down side to using a 1-8tw was so minimal it made the choice an easy one.

I think going with a 1-8tw keeps your options open a little better than does a 1-9tw barrel.

 

[Deleted member 46119]

I dislike "limitations".

In this case a limitation of a 9twist 7mm/284 would be having to stay at or below 180grain lead jacketed and below 150grain copper.

A 7mm WSM or 7mm/300 WSM can send the heavier bullets at a nice clip. Berger 195s and heavier copper come to mind and would like an 8twist more.

 

[TOM H]

Yep another barrel twist question.

I'm in the process of building a 7WSM. I prefer Bartlein, and will be going with a 3B profile.

I have read recommendations from 1-10 to 1-8. Looking at barrels that are available, I see most are 1-8, 1-8.5, and 1-9.

Bartlein has a 1-8.7 that would seem to fit the bill, as I'm looking to use 168-180's as the norm for this particular rifle.

However, does that kill me if I want to go with 140's?

Any other negatives to going with a 8.7 twist?

Why don't you call Bartlein and ask about 1/8.7 twist barrel and guessing those are barrels on bughole. Made few of them for a reason.

 

[FURMAN]

I think the 8.7 will be fine. I would shoot Berger 180s. I do not think the 195 will outrun the 180 ballistically. If you need the energy of the 195 I would consider a 30 cal. My 7WSM 9 twist would shoot 180 VLDs into one hole most days. The 3b seems to be a good balance for me.

 

[Blkz06]

I think the 8.7 will be fine. I would shoot Berger 180s. I do not think the 195 will outrun the 180 ballistically. If you need the energy of the 195 I would consider a 30 cal. My 7WSM 9 twist would shoot 180 VLDs into one hole most days. The 3b seems to be a good balance for me.

Thanks. I do have a 300 WSM, but it's a bit heavy. Took it on my Elk hunt and while it didn't kill me, I decided I needed something a few pounds lighter.

Was wanting to go with the 7wsm and use it for anything from mule deer to black bear, possibly Elk. I was told by a couple long range guys that the 168-180 would be perfect for those animals.

Then the twist rate discussion came in. Lol.

 

[elkaholic]

If you don't plan on shooting heavier than 180's or copper bullets, the 9 twist is fine. I have one on my 7ss and it shoots bug holes with the 180 bergers. .......Rich