Changing My Thinking About Slugs

[subscriber]

Received an email from Karen at Hart barrels.  They make up to 30" finished length .308 barrels in 1:8 twist.

[Scotchmo]

Received an email from Karen at Hart barrels.  They make up to 30" finished length .308 barrels in 1:8 twist.

30”?

That’s way too short. You’d need helium or air at 6000psi, neither of which I care to use.

[subscriber]

Received an email from Karen at Hart barrels.  They make up to 30" finished length .308 barrels in 1:8 twist.

30”?

That’s way too short. You’d need helium or air at 6000psi, neither of which I care to use.

Scott, I asked the barrel makers about 32" barrels.   I asked you what length you want, but other than confirming that 30" is too short, you have not stated what you want.

I can't help you, if you don't provide basic specs.  If you find my attempt to help you annoying, that would be an easy fix for me.

[subscriber]

OK, so I found another thread by you mentioning a 60" barrel.  Perhaps a variant of this 72" barrel could work for you: youtu.be/XCqa2umL8ME?feature=shared&t=97 ?

[subscriber]

The snag was that you missed my message quoted below, Scott.  Or ignored it.

Scott,

Would I be correct that you are looking for a 32" long .308 barrel with 1:8 twist, if you can get it?  If not, please correct me.

Now that I am better informed, it is obvious that the assumed 32" length is way short.

[subscriber]

Here is the contact info for the guy that made the extra long barrel in that video:

JURY CUSTOM BARRELS
RED DEER, AB

403-302-3005

bobjury@hotmail.com

OK, so I found another thread by you mentioning a 60" barrel.  Perhaps a variant of this 72" barrel could work for you: youtu.be/XCqa2umL8ME?feature=shared&t=97 ?

[Scotchmo]

The snag was that you missed my message quoted below, Scott.  Or ignored it.

Scott,

Would I be correct that you are looking for a 32" long .308 barrel with 1:8 twist, if you can get it?  If not, please correct me.

Now that I am better informed, it is obvious that the assumed 32" length is way short.

Yes. Sorry I missed that.

In order to explore the full transonic range using 2 to 4 caliber long projectiles, I need long barrels.

Here is where I’ve been and where I’m headed:

Far left: 72gr @1010fps in a .257 build (aka “Pea Shooter”). 36” long TJ 1:14 twist barrel. Used to win 2022 RMAC big bore match.

Middle: 105gr @1050fps in a 7mm build (aka “Sender”). 48” long TJ 1:14 twist barrel. Used to win 2023 and 2024 RMAC.

Right: 151gr and 171gr at 1080fps to 1180fps (goal) in a .308 build (aka “Mach Sender”). With a 61” long TJ 1:10 twist barrel. Still under development.

I had watched that 72” barrel chopping video sometime back. If there is no better option, it is possible to fasten shorter barrels together, like they did, but it’s something I prefer to avoid.

[subscriber]

Thank you, Scott

On general principle, I would avoid splicing a barrel too.  If someone can make you a single tube of the desired length and quality, so much the better.

My goal is to find options for you.  Just because I post something directly after finding it, does not suggest I think that to be the best option.  On the other hand, I don't like to sit on info I have, because I may never find the "best solution".  And then if I get distracted, may forget to communicate what I have.

If you were talking about larger calibers, I might have other custom barrel maker suggestions using single point cut rifling; although Bob Jury also does cut rifling in .308, from what I understand.  The Kibler guy in the video below is limited by the length of his Haas lathe, but who knows if his method may be adaptable to much longer barrels: 
youtube.com/watch?v=K6kHWZSK7Bg

[subscriber]

Bartlein barrels (info@bartleinbarrels.com) came back with 51” as the maximum barrel length they can make in .308 1:8.

[Scotchmo]

Bartlein barrels (info@bartleinbarrels.com) came back with 51” as the maximum barrel length they can make in .308 1:8.

Now that’s something I could work with. Any specific contours?

I did a little testing today before encountering another valve issue. I did manage to get a few shots off with the 170gr in the 1030fps range before the valve bound up and stuck open. If I can’t get the 170gr up to 1100 fps, not much point in a faster twist barrel.

[subscriber]

Any specific contours?

Bartlein offer a variety of contours, starting with the light weight ones at the top of the page.  Target barrel profile lower down:  https://www.bartleinbarrels.com/contour-details.

For an unusually long barrel, the contour could probably be anything you like.  They also offer fluting.  The beauty of cut rifled barrels is that fluting and contouring do not cause strange stress relief at the bore, compared to button rifled barrels.  Hammer forged also leaves a lot of stress in the barrel, while cut rifling is a gentle but very slow process.  That also makes it expensive.

If you are seriously interested, I suggest you contact Bartlein directly.


What would it take to talk TJ into hammer forging .308 liners with 1:8 twist?  Yes, it will take a new mandrel, but there may be potential .308 Blackout market potential to justify the new tooling.  I suspect that hammer forging may be the lowest cost option that can make super long barrels.  Even if they are not as good as the Bartlein barrels.