270 Win Twist Rates?

[BrettJolly]

Hello! I’m going to be rebarreling my current tikka 270 Win shortly so I can have it threaded for a suppressor and trying to decide on twist rate. Likely going with a 20”- 22” Carbon Six barrel.

Any insight on why you like or dislike a certain twist? What bullets do you shoot out of the faster twist barrels? Does an 8 twist still shoot the lighter 130s ok? Or only heavier bullets? Is an 8 or 9 twist going to shoot a 150 ABLR better than a 10?

I guess I’m looking for the most versatile twist rate possible, so I could shoot 165s if I want to reload them, or go back down to the 130s I currently shoot. Most likely I’m going to try to settle on either 150ablr or 145 eldx, but want to have options.

Thank you for any advice!

 

[BrettJolly]

Any insight on 270 barrels?

 

[jeremy.b]

I rebarreled a Tikka to a 1-7" twist to handle any mono I threw at it. Without wading into the pros/cons of monos vs lead I will say it has worked well for my setup and my projectile choices up to this point.

Unfortnately there is no perfect answer, faster twists work great for longer bullets, but can over spin light, thinner jacketed ones.

Take a really hard, honest look at what you want to run for projectiles, apply logic and see where it lands you!

 

[Formidilosus]

Any insight on 270 barrels?

There are no issues with an 8” twist and 130gr bullets. Not at all. There isn’t an issue with a 1-7” twist either.

 

[warrbuk]

Bullet RPM Calculator

Bullet RPM Calculator; Calculate Spin of a Bullet in RPM

www.findnchoose.net

I have read that 300,000 RPM’s is where you may start having problems


Sent from my iPhone using Tapatalk

 

[Unckebob]

I am waiting on a Criterion 270 barrel. It will have a 1-10 twist rate. I don't plan on shooting long, heavy bullets out of it.

 

[Triwayy]

It's good to see someone else building a fast twist 270. Mine will be a 270 WSM but that is just because I think the WSM case will launch the 170 grain with much better velocities than the standard 270 Win. I was hoping to find a 1:7.5" or a 1:7" twist rate. I think that the 170's would perform better with the slightly tighter twist.
have fun! shoot more!

 

[BrettJolly]

Went ahead and ordered the Carbon Six featherweight in a 8 twist. Looking forward to it

 

[Macintosh]

I rebarreled a Tikka to a 1-7" twist to handle any mono I threw at it. Without wading into the pros/cons of monos vs lead I will say it has worked well for my setup and my projectile choices up to this point.

Unfortnately there is no perfect answer, faster twists work great for longer bullets, but can over spin light, thinner jacketed ones.

Take a really hard, honest look at what you want to run for projectiles, apply logic and see where it lands you!

Which mono bullets have you had good luck shooting out of it?

 

[jeremy.b]

Which mono bullets have you had good luck shooting out of it?

139 gr absolute hammers. Feel free to ping me via PM for details.

 

[dingle]

What's the history on .270 factory barrels coming in a 1:10" twist if there's no downside to a 1:8"?

 

[jeremy.b]

It's my understanding the original design was for fairly light and fast bullets compared to it's parent '06. Also once a sammi spec is set (which includes some level of twist rate definition) it pretty much seals that twist rate going forward.

From there I suspect it's a matter of ammo and gun manufacturers likely not wanting to redo a ton of effort in ammo development to expand to other non-spec twist rates.

 

[JFK]

What's the history on .270 factory barrels coming in a 1:10" twist if there's no downside to a 1:8"?

They didn’t make .277 bullets that needed anything faster than a 1:10 when the 270 was introduced. That went on for several decades. Even today, the 1:10 barrels take care of an aweful lot of different bullets from 110-150gr. Most people do just fine with a 1:10 and it’s not going to hold you back in any meaningful way until you start really stretching it out.

That said….there is no reason why they shouldn’t be offering 270’s with faster twist barrels. People will say it’s a fudd caliber, but they should be spinning the barrels to utilize the full range of modern bullets. 308 is a donkey compared to 270 and the mfg’s have jumped all over that cartridge.

 

[cacklercrazy]

They didn’t make .277 bullets that needed anything faster than a 1:10 when the 270 was introduced. That went on for several decades. Even today, the 1:10 barrels take care of an aweful lot of different bullets from 110-150gr. Most people do just fine with a 1:10 and it’s not going to hold you back in any meaningful way until you start really stretching it out.

That said….there is no reason why they shouldn’t be offering 270’s with faster twist barrels. People will say it’s a fudd caliber, but they should be spinning the barrels to utilize the full range of modern bullets. 308 is a donkey compared to 270 and the mfg’s have jumped all over that cartridge.

Correct me if I'm wrong,but if you go to heavier bullets they will get longer and might not fit magazine lengths. I have a m70 been thinking about doing this to it.

 

[Unckebob]

What's the history on .270 factory barrels coming in a 1:10" twist if there's no downside to a 1:8"?

The 270 was designed to shoot flatter than the 30-06. To achieve that, they used a 130g bullet hauling @@@. They also reduced recoil. Later, a second standard load was the 150g.

They expected people needing heavier loads to buy a 30-06.

BTW - I don't think any heavy for caliber 277 bullets have been available until recently.

 

[JFK]

Correct me if I'm wrong,but if you go to heavier bullets they will get longer and might not fit magazine lengths. I have a m70 been thinking about doing this to it.

I don’t know the answer to this question, but I suppose it could be an issue. There are bullets that aren’t “heavy” that would still benefit from a faster twist. The 129gr LRX, some of the hammers, 130gr sciroccos. Those are the ones I have experience with. Even in 130gr those end up being close to mag length.

 

[dingle]

Thanks for the replies, everyone. Looking forward to hearing what direction the OP goes.

 

[BrettJolly]

Thanks for the replies, everyone. Looking forward to hearing what direction the OP goes.

I went with a 1:8 twist, 22” carbon six barrel. Going to be taking a close look at the new Barnes LRX 155gr .277 bullets just announced, should handle nearly any situation I come across from antelope to elk? Anyone have any other good ideas on do all, fast twist bullet?

 

[tankgijohn72]

Any of you guys shot the 155 yet?

 

[Seeknelk]

I almost did a fast twist 270. Like I almost found a shed once... I was planning to shoot the 170 berger for everything. I hate bouncing around between bullets.