Desirable Powders For 300 Grain Swift A-frames, For .375 H&H Magnum?

[charlieB12345]

Well I'm not inclined to do that. But I started at 73.5gr which is roughly the midpoint between max/min per my manual. I worked up from there, and particularly slowly when I reached maximum and kept going. Your rifle is not my rifle and as such, your maximum load may be different. So for both of our sakes, you need to go through the same process.

As always, particularly when approaching/exceeding max loads, you need to be paying attention to bolt lift and the expended brass after firing looking for high pressure signs.

Excellent advice! Thank you will do

 

[WyoBull]

The only powder I have ever used in my 375 H&H is RL15 because when I worked up a load with it I got such an accurate load without any pressure signs etc. that I did not even look to anything else.
Sounds like H4350 is a great one too from all the posts.

 

[Qc_BearHunter]

If you do get hold of it and can't get the other powders mentioned Norma 203B works like a charm.

RL 15 and Norma 203B are exactly the same powders.

 

[Nevada Mike]

I have used H4350, RL15, H380, and N150.

 

[charlieB12345]

IMR4350 did this for me

 

[Qc_BearHunter]

73,5 is plenty accurate. I have no problem hunting with a load that gave me 1,5" groups.

 

[charlieB12345]

Agreed!!

 

[DLSJR]

Only load I’ve shot is 70.0 grains of RL15, Federal 215 primer and 300 grain bullet. In my rifle the A frame, TSX and Bearclaw all shoot lights out and group together. It’s a great buffalo load.

 

[Frederik]

Other Powder that I have great results with is N540 as I cannot get hold of any Norma 203B I load a grain less than 203B seems it runs a bit faster.

 

[Rule 303]

The best powder I have used in my 2 375H&H is AR2209, this sells in the US as H4350. However my advice is beg, borrow or buy several different powders and see which your rifle likes best. I did have a CZ550 and now have a Rem 700 in 375H&H. AR2209 worked best for me in both rifles.

 

[F. Vaccaro]

Don’t overlook good old IMR 4064.

 

[cash_tx]

Don’t overlook good old IMR 4064.

That's a great powder for 375, but seems to be rare as hen's teeth at the moment, at least in North Texas.

 

[Bob Nelson 35Whelen]

I'm preparing for loading the referenced bullet for my new rifle. I have ordered the Swift manual but it's on backorder. Suggestions for powder for optimal loads with your own reloading efforts are greatly appreciated. I realize this is a poor time for reloading in general but found a new place to check into this weekend. So I can certainly use some pointers what to be on the watch for. Thanks in advance for your comments and advice.

@Trogon
Reload from a disc shows H4350 gives good velocity 2,600fps with a max load of 77gn of H4350 with a pressure of 50,000 cup.
This is a MAX LOAD
So the usual caveats apply.
START 5 GRAINS LOWER AND WORK UP TO A SAFE WORKING LOAD.
Bob

 

[Rule 303]

That's a great powder for 375, but seems to be rare as hen's teeth at the moment, at least in North Texas.

Ar2208 and Varget are the same as IMR4064. AR2209/H4350 give you the best velocity and has been extremely accurate in my 375's

 

[Rare Breed]

I'm still waiting for my 375H&H and playing around with potential loads on Quickload. The rifle in question is a CZ550 with the standard 25" barrel.

Using the 300gr A-Frame, it looks like VV N540 produces the best results. It reaches the 5th node at 2535 fps with 69.6gr powder for 92.8% case fill and 58531psi pressure.

With IMR4350 it can only reach the 6th node at 2442 fps with 71.5gr powder for 96.9% case fill and 48954psi pressure.

This is all theoretic, however it does sway me to at least start with VV N540.

In Quick Load using IMR4350 my loads of 73 grains for my Nosler 300 grain spitzerz produces right at 2500 FPS at 54,000 PSI when max is showing 62,000 PSI. 2500 FPS is plenty fast for my upcoming leopard hunt