375 Winchester CB hunting bullet in a Marlin

[OD Cleaver]

I almost asked this on ANDYM79's 375/38-55 post but didn't want to hijack the thread:

I just purchased an old Marlin (JM) in very good shape, caliber .375 Winchester, and can't find any jacketed bullets for it. The rifle will be used for big Ohio and West Virginia whitetails, and elk in Kentucky since my wife just drew a cow tag. All shooting will be done at 100 yards or less.

I've never used CBs in a Marlin, or cast/loaded for the 375 Win at all, and I'm very interested in mold and bullet weight recommendations to get me headed in the right direction. BTW I will be using .375 Winchester virgin brass, all 36 pieces I've managed to find so far.

Thanks in advance.

[6pt-sika]

I had a pair of the Marlin 375's both were made in 1980 . One I used with jacketed exclusively and the other was cast bullet only .

In the jacketed rifle I shot the Hornady 220 FP and Sierra 200 FP . In the cast gun I shot two Ranch Dog bullets , the 379-210GC and 379-235GC . Killed a little 7 point buck with the RD 379-210GC bullet and another with the Hornady 220 FP .

[garandsrus]

Do a search on Lyman 375449 and you should have a fair amount of reading to do. Many folks really like that boolit.

[TXGunNut]

Do a search on Lyman 375449 and you should have a fair amount of reading to do. Many folks really like that boolit.

The 375449 is a pretty awesome boolit for the 375 Win IMHO. Suspect you'll find a workable load around 32grs of Rx7, COAL 2.560"

[longranger]

Tom @ Accurate molds has a couple of bullets that are specific for the .375 Win. I don't know how different the Marlin barrels are compared to the Win.(.379) I have 2 molds from Accurate for this cartridge. 250gr. G/C to push fast 2000fps+ and a 300gr. P/B for killing big things. IMR 4759 is my preferred powder,IMR 3031 has been good with the lighter boolits.This rifle will put 5 in a ragged hole @50yds factory sights.

[OD Cleaver]

Any reccommendations as to what the CB should be sized to for the Marlin?

[JFE]

Probably best to determine your barrel's groove diameter, then work on 2-3 thou over your groove diameter. This is what is normally recommended.

[Trinidad Bill]

Do a search on Lyman 375449 and you should have a fair amount of reading to do. Many folks really like that boolit.

I really like that boolit! I use it for both my Marlin 38-55 and .375. If I were to use it for hunting .379-.380, GC and 32gr 3031.

[OD Cleaver]

This many experienced casters/shooters lauding the 375449 is enough for me, I'll try it. Any of y'all have personal experience with deer & elk sized game with this bullet? I've been shooting for 50 years, handloading for 40, casting for 1, and have never shot anything larger than a Texas jackrabbit with a cast bullet. This will be a year of reckoning for me.

[starmac]

Alaskaguy just come back from a coastal brown bear hunt, he was confident enough in that boolit to try for the beeg bears. I am thinking they would be the berrys for elk.

[26Charlie]

Mine casts 265 gr. and that bullet or the above mentioned Lyman at 275 gr. both work very nicely with about all the 3031 or 4895 you can cram into the case, about 35 gr. in the .375 brass. Cases made from .30-30 brass hold another grain IIRC, and as an aside all three guns I own in this caliber - Win 94, Marlin 375, and Ruger #3 will accept .38-55 brass.

[6pt-sika]

I used the Lyman 375449 , 375296 and the RCBS 37-250 in a Marlin 336CB 38-55 I had for awhile .

But when I was messing with the Marlin 375 I was more intrested in the RD bullets .

[6pt-sika]

Any reccommendations as to what the CB should be sized to for the Marlin?

I sized for the Marlin 375 and a Marlin 336CB 38-55 both at .379" !

[Trinidad Bill]

http://www.marlinowners.com/forum/32-40-38-55-375-other-great-non-standard-calibers/74008-marlin-38-55cb-hunting-loads-please.html

This is a good read on hunting bullets...

[OD Cleaver]

Very good read, thanks Bill. And thanks to all who helped with this, I'm ready to pour lead & make smoke, will hopefully post pics this fall.

[EDG]

I have a Marlin .375 made in 1981. The groove diameter measured .3778. You need at least .378 and .379 would be better if it is like my rifle.

[yeahbub]

I have a Marlin 375 and used to shoot the Hornay 220gr, but those just got too pricey. The mold that came with the Marlin is a Lyman 375248 and I struggled for some time trying to get cast to work in the Micro-groove rifling. Nothing to write home about until I tried paper patching. What a difference! It went from dinner plate groups to 2-3" at 100 yards with Reloader 7 and slightly better with AA1680. Cast of range scrap to air cooled WW's, patched, sized to .380 and backed by 28gr of 1680 (maximum in mine), it's got plenty of thump for deer and bigger. I'd not feel myself at a disadvantage going for elk and the deer never complained, nor did I ever have one fail to exit.

Good luck with it.

[bikerbeans]

OD,

I have a 1980 Marlin 375 and it likes both the 375449 and the RCBS 37-250. My rifle will shoot these two boolits to virtually the same POI with 24g of SR 4759 and a Win LR Primer. Both boolits are sized at .377" (my rifle will shot these boolits to about 1.5 MOA so I didn't bother to slug the barrel), water dropped COWW, gas checked and crimped with a Lee FCD in the crimp groove. I haven't chronograph the loads yet but per book data probably in the 1700 fps range.

BB

[OD Cleaver]

Thanks again to all who helped with this, I happen to know I'm getting the Lyman 375449 mold and other necessary's for my birthday in a couple weeks, so I'll report back after I've been to the range.

Trinidad Bill, I see you were in 'Nam 68-69, that was a mighty hot time to be over there, thank you for your service.

[TXGunNut]

I'd determine the size of the bore before ordering a mould, my 375449 drops @ .378 and a few posts are reporting generous bores in the Marlins. Lyman just came out with a new mould (380681) that drops .380 or .381 and it looks like a PB version of the 375449. Thread in the mould section.
Good luck making that brass last, have 100 new or once-fired and 40-50 well-used specimens around here. We may have to get creative when they run out.