gain twist ?

[1cougar]

Building a 6.5 x47 with a bartlein barrel was thinking about a gain twist barrel vs a 5r or 4R any advice on rifling choices thank you

 

[effendude]

My gain twist Bartlein 5R on my 28 Nosler is amazing. It is the only gain twist I own. I went with the gain twist to lessen the extreme start of the 195 gr, EOL bullets. All my other fast twist barrels seems to be fine with heavy for diameter bullets without the gain feature.

Scott

 

[dkhunt14]

If I was building a 6.5x47 I would do a straight 8 twist if you are planning on heavy bullets. Both 4 groove and 5R are good. I have never saw a gain twist shoot good at 1000 yard BR. The freebore needs to be right if you are shooting the 130 or 140 class bullets. Matt

 

[dragman]

I agree with Matt. a standard setup with proper freebore is all you need. I have never used a gain twist but I guess I see where effendude is coming from with a really large bullet for it's size like the 195's in 7mm.

 

[SHootSTraight22]

Building a 6.5 x47 with a bartlein barrel was thinking about a gain twist barrel vs a 5r or 4R any advice on rifling choices thank you

Butch's has 1-7.7 6mm gain twist barrels and 1-8.2 6.5mm barrels... I was thinking about trying one as well... My theory behind it had more to do with pressure increasing as the bullet makes it's way down to the faster twist end... They say a lot of ringer barrels get tighter towards the muzzle end and due to this gradual increase in pressure the barrel shoots better.. I figured this may could be recreated with a gain twist barrel spiking pressure at the muzzle end due to the faster twist there..

 

[maxpower]

If I was building a 6.5x47 I would do a straight 8 twist if you are planning on heavy bullets. Both 4 groove and 5R are good. I have never saw a gain twist shoot good at 1000 yard BR. The freebore needs to be right if you are shooting the 130 or 140 class bullets. Matt

Is that right, none ever shot good at 1000yds? Who is using the 6mm gain twists? Is it the 600yd BR guys?
Has anyone tried gain twist with the 7mm 195s? I am king of wondering how it will work with the long bearing surface?

 

[Paddyd]

While I realize the transition to the faster twist is gradual and constant it seems that the longer the bullet, there will be some part of the bullet being forced to spin faster while the tail end is still engaged in a slower twist putting unneeded stress on the bullet. Make sense? or am I looking at this all wrong?

 

[ballistic64]

While I realize the transition to the faster twist is gradual and constant it seems that the longer the bullet, there will be some part of the bullet being forced to spin faster while the tail end is still engaged in a slower twist putting unneeded stress on the bullet. Make sense? or am I looking at this all wrong?

Along those same lines, when the bullet is initially engraved by the lands in the beginning of the barrel and is forced into a faster twist, wouldn't the engraving from the lands be ever widening to the end of the barrel? Does this allow a path for gas to escape?

 

[SHootSTraight22]

Is that right, none ever shot good at 1000yds? Who is using the 6mm gain twists? Is it the 600yd BR guys?
Has anyone tried gain twist with the 7mm 195s? I am king of wondering how it will work with the long bearing surface?

Call Aaron at Butchs Reloading and verbally ask your question... I think they are using gain twist...

 

[SHootSTraight22]

While I realize the transition to the faster twist is gradual and constant it seems that the longer the bullet, there will be some part of the bullet being forced to spin faster while the tail end is still engaged in a slower twist putting unneeded stress on the bullet. Make sense? or am I looking at this all wrong?

Bryan Morgan used one in PRS.. He can shoot also!!