suggest a boolit weight for me

[Haywire Haywood]

I'm getting a 375 Winchester (24" barrel). Can someone with some load software tell me what the heaviest bullet is that I'll be able to get to 1900-2000fps at the muzzle.

much thanks,
Ian

[Buckshot]

...............Haywire, You're probably looking at a 220gr slug. I think the Winchester factory 200 gr was a 2200 fps number.

Hodgdon shows:

220 GR. HDY JFP COL: 2.500"

H322 38.5 C 2236 48,900 CUP
H4198 34.0 2233 49,300 CUP

The Lee reloading manual has quite a lot.

................Buckshot

[Haywire Haywood]

I was browsing my reloading manuals, and saw a 235 that barely reached 2000 with just one powder and 220gr that went 2200 with several, so using my keen sense of deductive reasoning :roll: , I figured a 230 would comfortably reach the 2000 mark without pushing the max so hard as the 235. This is condom bullet info tho so I don't know how that will translate to cast as far as velocities go. I'm trying to settle on a weight for a MM mold whenever Dan gets his shop built. There's a 4 month lead time on the barrel I just sent off for reboring so there's no rush.

Ian

[9.3X62AL]

A kind of general rule is that cast boolits take a bit less pressure to achieve a given velocity level than do j-words of the same weight and shape, all other things being equal--this due to much less friction imparted by the cast boolit's metallurgy than is imparted by the gilding metal jacket.

The 375 Winchester or its ancestor the 38-55 has always seemed like a real fine cast boolit hunting caliber to me. I largely duplicate the performance of the 38-55 in my 9.3 x 62 using 270 grain MM boolits. The 38-55 used 255 grainers, but that's not a huge difference. I had my mouth all set to get one of the Winchester 94's in 38-55 this year, but that's a non-starter now.

Good luck with that 375 project! What twist rate is the barrel being made with?

[Leftoverdj]

Lee #2 claims you can do it with a 250 grain bullet. My guess is that it would be fairly easy with a singleshot throated out a bit, and borderline with a magazine imposed length restriction.

[beagle]

I'd go with a 250 grainer. You didn't say what you were building it on. With a lever, a 250 at 2,000 FPS is going to give you a big thump on both ends.

I built a Number 1 Ruger in .38/55 with a 1-16 twist barrel. Being as that action's strong as a bank vault, I can use .375 Win cases and really open the throttle. The best of both worlds.

I'm kind of partial to Lyman's old #375296 if you can find one./beagle

[Haywire Haywood]

This is an NEF Handi-Rifle break action single shot. I had a 24" 223 Ultra barrel fitted to it then sent the barrel out to Wayne York at Oregunsmithing for the rebore/rechamber.

As for the twist, I intended for it to be a 1 in 18, as when I was playing around with the bullet design page at Dan's site, there was nothing in the 200-265 weight range that the 18 wouldn't stabilize. What makes me want to get a faster twist is the fact that the factory leverguns had a 1 in 12 twist. I can't figure that one out. If Dan's page is right, that 12 twist should stabilize a 405gr bullet. I'm considering bumping it to a 16 twist. That will take me to 300gr, altho I have no intention of loading anything above a 250.

Ian

[JohnH]

Haywire, MY 375 JDJ has a 1:12 twist and I have found absolutely no advantage to it with cast. Jackets like it just fine, but the reality is it ain't needed. A 1:16 will stabilise the Lyman 335 grainer just fine and that boolit is 1 5/16" long. I imagine the 1:12 twist is a result of the 375 H&H, which was concieved using bullets as heavy as 350 grains, which with your case capacity would be a ballistic absurdity. I had absolutely no trouble with my NEF 38-55 with the 1:18 twist stabilizing 270 grian bullets, and there is little that a heavier bullet than that will do for you in a hunting rifle. I found the Lee 250 to be an exellent bullet in my 38-55, and am currently enjoying some good accuracy from it in my JDJ. At some point I want to try the RCBS 250 GC, I'd bet that would make a nice deer plunker, but the Lyman 379449 and the Lee 250 are for practical purposes as good as it gets. A 375/38-55 is at the top of my "I want a barrel" list, perhaps tax time will allow it next spring.

[Buckshot]

..............My 375-06 has a 12" twist and is a superb shooter with jacketed, but trying to push cast has issues over about 1600 fps. I CAN get sub 3" 5 shot groups at 100 yards with cast over 2100 fps but I had to use 328 and 352gr slugs.

...............Buckshot

[lar45]

Looked at quickload and the 270 Speer.
28gns 1680 = 1980fps @ 61ksi
26gns RL7 = 1925fps @ 51.4ksi
24gns H4227 = 1895fps @ 53.2ksi

FWIW

The Lee 250 looks like a pretty fair bullet to me.

What I want to try if I ever get around to it, is shooting empty 9mm cases. Talk about a light huge hollow point! Or cut down a 223 slightly, fill with WW and have a 400gn brass case super bullet.

I also want to try some 45 acp cases in the 475 linebaugh and the 470 NE.

[Doughty]

Haywire,

Several years back I was shooting the .375 Win in the Marlin lever action and the Ruger #3. I was using the Lyman gas checked bullet , which was labeled as being 265 grains, but out of the mold I had, when cast with WWs, checked and lubed it was 280 grains.

Using AA2015 I could get some accurate loads at 1900 fps. These shot good in the #3, but seemed too much for the Marlin. IMR 4198 was also a pretty good powder.

I am currently working on a .375 using the .30-40 case. Hope to be able to get to the 2200 fps range with a 300+ bullet.

Good luck with your project.

[Bass Ackward]

I'm getting a 375 Winchester (24" barrel). Can someone with some load software tell me what the heaviest bullet is that I'll be able to get to 1900-2000fps at the muzzle.

much thanks,
Ian

Ian,

Because of the barrel lengh, you have some options at 250, but clearly the widest options of doing it at cast bullet pressures comes from a 225 or less grain bullet. you might get lucky up there. And you may just feel that 1850 is good enough, so you will have options.

And I am another one that says don't over twist.

[Haywire Haywood]

Thanks for all the input . I borrowed some manuals that I didn't have (Lee and the new Lyman #48) for some additional info. I think what I'll do is get some boolits from a buddy that has a 38-55 and a 376 Steyr and shoot it before I order the MM mold. Still undecided on the twist rate tho... 16 or 18. Good thing I have 4 more months to figure it out.

Ian