It's been a while since I rolled this old rifle out, but am going to Mozambique next year for buffalo, likely in wet conditions and my rifle is a pleasure to carry at 7 lbs. Kind of teeth jarring too, but only when you shoot.

So I need to fire form some 375 H&H brass, and figured on shooting light bullets with the Speer reduced loads for SR 4759. That should produce plenty of pressure to well form the case, and save a lot of mess compared to the pistol powder and cream of wheat method I've used before.

The forum members consistently have lots of experience, so I'm asking for some feedback. Anybody have any thoughts on this?

Doesn't Norma or someone already make 375 Wby headstamped brass so you can skip fireforming and go straight to load development?

I just load up some cheap 220g hornadys with IMR4064 and go shoot

Shooters Pro Shop has 375 Weatherby brass for $30.00 a box. I bought some last month.

LD

I'll throw in on this. As prewar70 stated, I do believe I have seen this brass offered. I had planned to form .375 H&H brass for my .358 STA, but find that for the cost of Norma brass, powder, bullets, and primers, I can buy formed and correctly headstamped Superior brass for the same $. No fireforming necessary, just go directly to load development.

Ummm, well, yes I could use the right brass to begin with. But I have 200 rounds of bright, shiny new 375 H&H that I got for well under $100. I'd like to use those. Can always fall back and buy some of the factory brass, but in the meantime....

I've been using IMR 4064 one grain over a max H&H load with the 270 gr Hornadays to fireform brass for my 375 Weatherby . This gets you pretty close to factory load H&H recoil and velocity when fired in the Weatherby chamber .

I don't see the extra shooting as a disadvantage , you are going to want to be pretty familiar with that sort of gun at any rate . I'm sure there are other medium burning rate powders that would work just as good as 4064 , but I've got a couple of unused lbs on hand........

Another thought........you may need properly headstamped brass to match your rifle for going overseas......in that case you are going to have to pony up for the Weatherby brass.....

Hi, since you are going to Mozambique please check that you can bring ammo stamped with 375H&H and a rifle stamped 375 Wby.
In some countries the customs can give you a hard time trying to bring ammo not correctly labeled.
I belive Craig Boddington mentioned this problem in his great book.: Safari Rifles.
PS. check with your booking agent if you trust the info given.
It's bad to get a 5000$ hunt ruined for 100$ brass...

quote:

So I need to fire form some 375 H&H brass, and figured on shooting light bullets with the Speer reduced loads for SR 4759. That should produce plenty of pressure to well form the case, and save a lot of mess compared to the pistol powder and cream of wheat method I've used before.

Ought to work just fine. Try a few just to assure that they produce ample pressure to fully fire-form to your chamber (I can't imagine that they won't). Shooting reduced loads for fireforming is much preferable to the Rube Goodberg method of filling the case with some kind of crap and hoping that it works.

By the way, I would urge you to try some full-power loads as you are fireforming. It has been my experience that there is little or no loss of accuracy with unformed cases, and you can load to the same velocity, provided you're not using a powder so slow that you run out of room in the unformed case. Why waste a shot just on fireforming if the fireforming loads perform as well as the formed loads?

sdgunslinger and others that have recommended relatively light bullets with full power H & H loads are correct. I wouldn't use the SR4759 because generating sufficient pressure to reliably fireform with that type of powder may bring you too close to the critical pressure levels. A 235 - 270 gr. bullet with a full charge of 4064 for the H & H loading will do the job right.

Correct headstamped brass is available.

http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=712830


ZM

Thanks for the suggestions. Headstamping is not a problem since my barrel simply says "375 MAG".

I also know that I can shoot factory H&H ammo and it does just fine. Slower, but just fine, and if ammo goes astray I can fall back to that option. But with this really short barrel, (20")I'd prefer to go with the Weatherby dimensioned case.
I'll shoot a few with the 4759 and measure some cases to see if they've fully formed. If not, I can always go to a more powerful load.

Interesting side note - courtesy of my Dad's purchase when new, I have a box of 235 grain Speers, and the address on the box has no zip code. Has to be 40 years plus in age. Almost hate to shoot 'em up.

Fire formed today without a hitch. The old 375 H&H cases are now 375 Weatherby. Of course before I actually loaded, I took one more read through the manuals looking for info on fire forming cases. My old Speer manual cautioned against used reduced loads as they might not reliably exert enough pressur to completely fireform the case.

Took their advice, used RL 15 at the recommended minimum, and all went well.

Cases do turn out a bit short though - means a little less neck to work with. Since they headspace on the belt and not the OAL, that's not gonna be a problem.

Thought I'd report in, just in case anybody else want to fireform at minimum bullet weight AND minimum velocity.