357 H&H to 375 Weatherby fire forming - Brass options?

Mudduck

Mudduck

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I now have a 375 Weatherby. I refuse to pay the price for 375 Weatherby brass .. so Im looking at fire forming some 375 H&H brass - Hornady, Remington, Winchester or PRVI
Does anyone have any experience with PRVI 375 H&H brass. They are priced is better then any of the others about $40 less per hundred cases.

To fire form these cases does anyone have a recipe for how much powder etc I should use
I have never had to fire form brass before so this should be a new experience
I have lots of IMR 4350 so I would prefer to use this powder
 
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All of my fireforming has been done with a normal load for the parent cartridge. I use these loads to do initial sighting in and practice with a new rifle. These loads, which are assumed to be full power, usually do a nice job of fireforming the cases.
 
I have fire formed brass (270 to 30-06) by using hand gun powder and corn meal.
Really the best thing to do is get yourself any books on reloading, that's where I got my info but I do not have my books out at this time.
If you don't find any good info soon, PM me and I will dig out my books and find some info for you. You can get these books anywhere they sell reloading components.
 
The cornmeal method on top of probably 6 or7 grains of pistol powder and tissue to keep it in.I use 5 grains in 308 cases when building 7-08.

No wasted bullets, no barrel wear, no expensive rifle powder going to waste, and to be honest, pretty fast , just gotta watch for build up of product from the corn meal.
 
If you are going to buy .375 brass, then pay for bullets, powder and primers you may just want buy some cheaper factory loads in the brand of your choice and shoot that. There isn't that much difference in price, and you don't even have to load it.

To build on that theme a bit, Cabela's sells .375 Weatherby brass for $68 bucks a box last time I looked. That's about what cheaper factory .375 H&H ammo runs around here. When I run the numbers you can end up with once fired Remchesteral brass or new Weatherby for the same money. Sure there is some value in plinking ammo while you're fireforming; but there is a real dollar value difference between once fired Winchester (never mind that nobody can find that in brass form) and brand-new Weatherby too.

If you are willing to forego the difference in brass quality and life, and just want to get your rifle shooting as cheaply as possible you have to get the price of the bullets and powder out of the equation. You can fireform for almost no cost but time, if you use a small charge of pistol powder and a case full of Cream of Wheat, and no bullet.
 
I have a 375 Wby that's never seen a factory round. I use hard cast bullets from Bullet Barn to fire form. Sized to .376 or .377 perfect for forming brass. Cast 375's are a viable hunting option too. BB offers a 265 gr gas check bullet sized .376. Lyman load manuals have load data.
 
.375 Wby, and you go cheap on brass? Just saying. The amount you are going to shoot the thing- it does bite back - the difference in price of Weatherby brass in .375 Wby, and fire formed .375 just does not compute. In my book, anyway. Buy Weatherby brass - still made by Norma, I think - and enjoy several reloads without the fuss.
 
ykkid said:
.375 Wby, and you go cheap on brass? Just saying. The amount you are going to shoot the thing- it does bite back - the difference in price of Weatherby brass in .375 Wby, and fire formed .375 just does not compute. In my book, anyway. Buy Weatherby brass - still made by Norma, I think - and enjoy several reloads without the fuss.
Click to expand...

375 Wby brass / 100 rounds:
Weatherby $335.00
Norma $380.00
Winchester 375 H&H $67.00
Remington 375 H&H $80.00
I still have 100 rounds of Winchester 375 H&H that was fire formed in 375 Wby in the mid-eighties. On their fifth reload.
 
Mudduck Usually the reason someone fireforms a case to an "improved cartridge" is to increase case capacity (so a higher velocity can be obtained) or to improve headspacingor to get away from expensive brass. Since the Wby is an improved H&H you are doing 2 of these. If you want maximum capacity in your fireformed cases use the case with the most capacity in the std form. You can weigh the cases to give you an indication (lighter cases will have more capacity) or you can fill the case with a fine ball powder and weigh it. I think you will find that the Win brand case will have the highest capacity and the brass will be as hard as any. I have found that for every 10 grs more a case weighs it will reduce the powder capacity by approx. 1 gr. That is why you will often see a warning in loading manuals for 308 and 30-06 cases that if military brass is used reduce powder charge by a couple grs. However back to your Privi brass. I have not used it in 375 cal but I have used it in several other calibres and it is quite good brass. I have found the case capacity to be slightly less than Win or fed and even Rem cases. My 375 Wby has never seen a Wby case I have fireformed Win brass. I have found that full power loads in 375 H&H cases shoot to the same spot as the same load shoots to in fireformed cases (in my rifle).A near max load(for the 375 H&H)of a mid range burning powder such as 4895is a mid load for the 375 Wby and fireforms cases very nicely. If you choose to use a slower powder such as 4350 you are going to want to use a near max H&H load. I would suggest loading up 2or 3 rounds to try first.If the pressure is too low the radius shoulders may not blow out fully and you will need a few grs more powder or go to a faster powder such as 4895. Hope that helps.
 
Dogleg My rifle has a 26 in barrel and 270 gr bullets can be started at 2850 without excessive pressure. I have not loaded many 300 gr bullets mostly because I just can't afford a trip to Africa and I don't see much of a need for the 300 gr in NA . However another bullet that is truly spectacular is the 250 gr Barnes TTSX. It can be driven to 3000 fps quite easily and it's trajectory and performance on elk and moose is incredible. You may be able to squeeze a little more but I am satisfied with those velocities at reasonable pressures coupled with good accuracy so that's where I stopped. The little experience I do have with the 300 gr bullets is with the 300 gr sierra. They shoot very accurately, recoil is up from the 270 gr. 4350 would be excellent in the 375 Wby with 300 gr bullets. Hope that helps
 
I'm getting 2800 fps with 300s, 2950 fps with 270s and over 3000 with 275 CEBs. That's with Weatherby brass that is showing every indication of wanting to live forever. The barrel is a 26" Bevin King with a very long, old style free-bore.

Interesting caliber this one, with over 2 1/2 tons of muzzle energy out of a little .375. Hook that up with suitable bullets for the task and good things are going to happen.
 
Hey guys thanks for all the input, Chinbullco, Rokoro, Dogleg as well as others great information. I'm looking forward to a whole new experience with this rifle. Bought some H&h Hornady brass yesterday ... I get 50 pieces for the same price as 20 Weatherby brass and I have a nice Swarovsksi Z6 scope waiting for it.
The only thing that disappoints me is Forster doesn't makes dies for the 375 Weatherby :(
 
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