School me please, .375 CheyTac LRB and bullet selection

[DanGuy48]

So, I'm going to try one more time to get into LR shooting. I have an older rifle that I bought before I retired (back when I had money). I didn't have time to do anything then, bought it for when I retired. I retired, things went south for a while (wife had cancer, multiple surgeries, chem, radiation etc. now doing better) so I'm hoping to finally start on this before I'm too decrepit to carry a rifle.

The (possible?) problem is I have a .375 CheyTac made when Lawton was in its heyday. It is an 8000 action, Lawton barrel and muzzle brake; the barrel is the 11.5 twist Lost River Bore. I am totally confused right now, after reading on the web most of the afternoon, about what bullets to use. I had a number of e-mails saved with this but I just discovered they are gone.

So, my questions are:

-- Can someone tell me, or point me to, the actual dimensions of a LRB barrel vs. standard bore? Maybe I could figure out the rest from that.

-- Are drive band solids OK with this combo? What about standard lead core bullets?

-- has anyone published (semi?) official load data for this round? I have seen some discussion on this but would like as much info as possible.

Thanks in advance for any help.

 

[royinidaho]

Sounds like you're between a rock and a hard place.....

You're to be respected for taking good care of the mrs.

Lost River Bore - I have only a suspicion. It may mean a tight bore. As in a bit under sized. Not sure though.

Back in the day when Lost River Bullets was producing bullets, copper solids/machined bullets, they required a "tight" bore to function up to snuff for the most part.

I used their 270 offerings in a Lilja barrel, which are reputed to be on the tight side, and did well. Then Lost River went kaput.....

I shoot a 10 twist 375 CT Improved (Allen Magnum). Bullet selection is somewhat limited. Having said that how many different bullets are necessary for that big sucker.

The 350 Sierra Match King should function well in your 11.5 twist. Or at least I would hope so. They are exceptional in my barrel though they don't compete with the Cutting Edge Bullet offerings of 375/377 grain and above offerings.

The CEB 330 grain and below should do well in your barrel.

Go here: https://cuttingedgebullets.com/cgi-bin/commerce.cgi?search=action&category=1375 and check things out.

Goto powders are Retumbo, H-50 BMG and RL-50.

Go here for load data then start way low and work up. Noting that the Allen Mags are a fair bit larger than the standard CT necked to 375. Home Page

I shoot 142.5 gr Retumbo with the 350 SMK for 3250 FPS MV. and 139 grains of 50-BMG and the 377 Cutting Edge for 3185 FPS. The driving band works just fine. Again, keep in mind that the Allen Mags are a bit on the extreme side of the scale thus think way smaller charges to start with.

I'm betting if you asked real nice Cutting Edge would send you a sample bullet to see if it fit properly in your bore. Except for the "band" they are bore riders and should be able to be slid into you muzzle. If not, she's way too tight....... Or I could send you one but you'd have to promise to send it back. (I'm cheap and covet those things.:roll eyes

Also in the upper right of the forum page is a "search" window. Enter '375 Chey Tac' and see what pops up.

Hope this helps.

 

[DanGuy48]

Thank you for the thoughtful reply. I will look into the references you made. Your CheyTac does seem to be running a significantly heavier load than what I remember the standard round does, but I need to familiarize myself more before I start. I have 2 lbs. of Retumbo that I bought to start reloading. I had fired some rounds made by Hunting Shack, I think it was, to generate brass for a Warner die for my chamber. That's about where things got left and I lost all my e-mail notes I had saved. I still need a good seating die and was thinking about getting one from Viersco.

....sigh.....

Maybe I'll go dig on another old computer I was using at that time and see if I downloaded any of those e-mails to my hard drive.