375 Win

[Brad]

I listened to Tom and got a 38-200 AG mould for my 375 Win. They drop at .381 and I'm sizing to .379+.
Took me some time to get on paper at 100 using a load close to what Tom suggested. With 25 gr of 5744 and a 200 gr bullet I got just over 1700 fps. Accuracy was pretty good considering the front bead is too big and my target was too small.

I'm liking the rifle much better with a lighter bullet.

 

[Ian]

.35 Remington "lite". Good for you, sounds like a lot of fun.

 

[oscarflytyer]

Gonna recut the Marlin 30-30 to 38-55/375 by Jes. Keep sayin' it, just need to DO it! Hav dies and mold already. Every time I get ready something else tempting depletes the cash (like a pre-64 94 and then a pair of old 16 ga pumps!)

 

[AMTom]

38-55 brass? Is the front band engaging the leade upon chambering? A bit of resistance closing the lever?
If not, try .380" sizing.

 

[Brad]

Yes, 38-55 brass. I don't get any engraving that I can see. I will try an unsized bullet and see if it engraves.
I flared a new case and chambered it. The flare wasn't touched so I'm sure the chamber is plenty long for the case.
Tom, mine is the shorter Starline brass. Should I try the longer?

 

[AMTom]

If your bullet can engage barrel steel upon chambering it will make a big difference in accuracy.
It's easy to measure whether the 2.125" brass will be better than the 2.08".

Chamber test a cartridge with the bullet extended to a length which engages. Does it show that you need another .045" of case length to crimp at that OAL?

Naturally, you'll need to test a flared 2.125" case to make sure it's safe. But I have found that the distance from case mouth to leade is quite consistent in these rifles. Logical, since the chamber reamer cuts both features at once. The question is how deep did they run the reamer? Headspacing on the rim allows them to be sloppy about it.

 

[Brad]

Easy enough to do. Gives me a project for later in the week.