375 Winchester OAL question Lymam 375449

[rda72927]

Working on the first 375 Win loads for my brother and I'm using a GC Lyman 375449. The data I have from the Lyman Cast Bullet Handbook, listed the OAL as 2.560. So, here is a picture of a couple of dummy rounds. The one on the bottom is at 2.560 and the next is at 2.430 and the 375449. Looking at the picture, looks like a whole lube ring above the case rim. This is the first levergun I have loaded for. So, which OAL would you use?

172056

[ohiochuck]

In his book Clyde "Snooky" Williamson "The Winchester Lever Legacy" listed the OAL loaded cast bullet as 2.420". He was loading the same boolit 375449. He used it in the Winchester 375 Big Bore rifle
Jim

[runfiverun]

I use that same combination and crimp under the front drive band for about 2.470.
it feeds in both my win 375BB and in my marlin 375.
it shoots well in both of them too, sized to 379.

[TXGunNut]

I'll have to check when I get home but I'm pretty sure I used the Lyman OAL of 2.560 in my Winchester Big Bore. When I lube with NRA 50/50 or another White Label lube (brain gas) I only lube the first two grooves anyway. If you have any Reloder #7 around take a hard look at the loads in the Lyman manual.

[JFE]

Unlike most levergun cartridges the 375 Win has a long throat. The Lyman bullet was originally designed for the longer 38/55 (hence the short nose) but works in many 375 calibres. For the 375 Win you can crimp in either location, though crimping into the lube groove will do a better job of filling the long throat and likely result in better accuracy.

[JFE]

With this cartridge and indeed for most levergun cartridges, it's handy to have a Lee FCD so you can crimp in locations where there is no crimp groove.

[TXGunNut]

Just checked; my BB likes the 375449 seated to 2.560 over 32.0grs Rx7. This is a max load according to the 4th Edition Lyman manual so of course you will need to reduce by 10% and work up.

[dh2]

I am using the same mold for my .375 H&H Mag. I do set it like your longer one in the pic. and it preforms very well.
I would have my COL as long as the rifle would allow

[gundownunder]

I don't own a 375, though I think maybe I should. My thinking is, if your rifle will cycle the longer load you get more powder room.
I've also often heard that the closer you can get your bullet to the rifling the more accurate your load will be.

[runfiverun]

I think you don't need any more powder room in the 375.
I need to slow my loads down for the Winchester some, I have the sights bottomed out and the poi is 200 yds.
my marlin needs the faster loads to correspond to it's sights at 50-100yds.