22 creed gain twist

[Hattrick]

Ok looking to build another and my last custom lol. Whats your experience with the gain twist on the 22 creed ? I‘ll start Gathering components her shortly and get a 24” barrel bartilne ordered it will be LH twist I’m thinking gain twist 7.5-8.5 or 9? not sure how much they can go I guess Bartline can point me in the right direction on that. Built on a terminus action looking to run heavies fast. Curious as to how versatile the gain twist can be for this rig? Any advice is Appreciated

 

[308Gunner]

Don’t know on the 22 creed but my 6.5 SLR has a 1-9 to a 1-7 left twist on it. It is a hammer

 

[DIBBS]

Based on my limited research, I plan to go with an 8 twist .219 bore and shoot 75-80 grain bullets when I have a barrel spun up. There have been reports of the tighter bores/faster twist causing bullets to poof before reaching the target.

If I can find the discussion on 22 Creedmoors I will post a link here. I'm not sure how the gain twist would work on stressing the bullets.

@Frank Green what would you recommend?

 

[Hattrick]

Thanks that would be great

 

[Frank Green]

Based on my limited research, I plan to go with an 8 twist .219 bore and shoot 75-80 grain bullets when I have a barrel spun up. There have been reports of the tighter bores/faster twist causing bullets to poof before reaching the target.

If I can find the discussion on 22 Creedmoors I will post a link here. I'm not sure how the gain twist would work on stressing the bullets.

@Frank Green what would you recommend?

75 to 80gr bullets and depending on which bullet at 22CM velocities...you might even get away with shooting a 1-8.5 twist.

Stay away from a tight bore.....! That extra deeper engraving a .218" type bore is going to do....you're asking for problems. A .0005" per side doesn't sound like much but that extra engraving depth on the match style jackets and if you run conventional 4 groove or 6 groove rifling....just going to make things worse.

The tight bore barrel isn't going to give you better accuracy and or more barrel life. Say what you want but the answer is going to be a no, zip, zero, nada, not going to happen from me.

If you run a tight bore....I would strongly insist you run 5R rifling.

If it was my pick for my personal gun.....5R rifling and standard .219" bore.

As you start approaching and the hard line in the sand is 300k rpm bullet speed. Bullet failure is going to happen. Your just on borrowed time. It gets worse when the throat area of the barrel starts to get rough from wear as well.

For rough numbers...at 3400fps and in a 7 twist barrel that's going to give you almost 350k bullet rpm.

At 3400fps in a 8 twist barrel your at 306k rpm.

Take velocity x 720 and divide by twist = rpm

I can see the gain twist helping starting out the bullet a little slower rpm wise but you have to keep in mind your ending twist has to be fast enough to stabilize the bullet still. Will the GT rifling be a cure all? I'll say no. You cannot fool mother nature or in this case the laws of physics of high velocity, chamber pressure, bullet rpm, type of bullet, how hot the barrel gets...how many rounds on the barrel etc...are all going to play a factor.

We all want to go fast.....but we are going to pay for it somewhere. No way around it.

Later, Frank

 

[Hattrick]

Frank thanks for chiming in I was out of town and no Reception. Just curious have you seen a sweet spot with the amount of gain twist and how much is too aggressive ?

 

[4O6shootist]

219 is the way to go! 237 in 6mm too.