300 Grain A frame 375 H&H

[Deleted member 46122]

I found this load in my old Lyman #49
It seems a bit “warm” but I’m thinking about loading a handful to see how they act.
any thoughts?

 

[PHOENIX PHIL]

My M70 loves IMR4350 and a 300gr A-Frame. Your Lyman manual seems a little off. The 270gr max load is 77.7gr of IMR4350 while it's 81.0gr for the 300gr version. That makes no sense to me.

I believe the current Swift manual still shows 75gr max of IMR4350 for the 300gr. Years ago someone here on AH, forgot who, share their load with me. It is above the 75gr max listed. I won't say exactly what it is. But I'd recommend starting at mid range of what the Swift manual says and work up from there. As with any load above or below max listed, be aware of pressure signs.

 

[colorado]

I get 2800 fps out of my 375 Weatherby (Rem XCR II 24" barrel) with 300g Partitions and A-Frames. You should get at least 2500 fps out of 375 H&H

 

[Whacker]

@Kevin Peacocke I would be careful with that old load shown. Current load data from Hodgdon website on IMR-4350 shows 75.0gr as a compressed max load with 300gr Swift bullet. Hodgdon data is normally what I use as it is higher normally than my Hornady book. Here is a copy of the Hodgdon load data for IMR-4350.

 

[Deleted member 46122]

I agree with all the above comments.
this is a very compressed load even at 80 grains.
I thought it seemed “odd”

 

[Whacker]

I agree with all the above comments.
this is a very compressed load even at 80 grains.
I thought it seemed “odd”

Sry idk what happened with addressing that to the wrong person above...been a very long tiring day I guess I apologize. I was looking though and the old Load you had looked very much identical to some 375 Ruger loads I’ve seen...think it’s possible it was a misprint in the manual?

 

[dchamp]

The Swift Manual lists starting load for 300gr AF & IMR4350 at 71.1grs, 2404fps and max load at 76.5grs, 2602fps & 98% fill capacity.
QuickLoad indicates 74.0grs of IMR4350 is 100% fill capacity going around 2550 fps and 63,743psi. It lists Pmax for the .375H&H at 62,366psi.

 

[Deleted member 46122]

Ahhh thank you

 

[Quaticman]

I can't comment on thay particular load however what I can say is that I used factory loaded 300 grain Swift A-Frame (Remington Safari) ammunition on my Namibian plains game safari and it performed flawlessly. Kudu, Oryx, Springbok, Hartmanns Mountain Zebra, Warthog and Baboon were no match for the 300 grain Swift A-Frame fired from my Winchester model 70 chambered .375 H & H magnum.

 

[colorado]

The 300g A-Frame is a wonderful bullet. I used the same ammunition on my Alaskan brown bear at 13 yards Penetrated him diagonally starting at the right shoulder, ended up in the hide of the left thigh. Expanded beautifully and still weighed 299.5 grains.

 

[Deleted member 46122]

Thank you gentlemen for all the useful comments.
I tend to follow the load data for any given bullet fairly closely.
To that end, I’ve loaded a box with 76.5 grains IMR 4350 and a handful at 77 grains, same powder. Will see how they shoot this weekend if I get to go to the cabin.
should be fun.

 

[Mike Van Horn]

Seems they have the 270 grain and the 300 grain data swapped. This is way you should check more than one source when starting a new load

 

[Deleted member 46122]

I agree. That’s why I started out questioning the load data from the old Lyman

 

[Deleted member 46122]

I agree. That’s why I started out questioning the load data from the old Lyman