Home Forums Hunting & Shooting Africa Question re .458 Win and 500 gr Hornady DGX loads

I'm getting set to load up some 500 gr Hornady DGXs for my Win M70 .458. In looking at load data published by Hornady's 10th Edition, it lists a max load of 76.9 gr of Accurate 2230 for 2150 fps, and 78.3 gr for 2200 fps and a COL of 3.310". This seems significantly higher than Western Powders max load of 72.0 gr of Accurate 2230 for 2159 fps and a COL of 3.305". Why is there such a big difference and which data should I follow in working up a load?

Other than a joke about a suitable minimum for elk, I would suggest you pick the velocity you want to use with that bullet using that powder, load up one of each at some staggered charge, like starting at 70 grains, load one, then one at 71, and 72, and 73, and so on. Shoot them over a chronograph until you get your target velocity. Then duplicate that load. If you want 2150, you may have to get near the top end of SAAMI pressure for the cartridge to get there. If you want 2200, you may have to step on it a bit more. Regardless of Hornady's results, if you want to stick within SAAMI loading specs for the cartridge, trust the powder company more than the bullet company. In other words, if Western claims a top speed of 2159, chances are you are going to be exceeding top pressure level for the cartridge by at least a hair to get to 2200, all other things being equal (brass, primers, barrel length). Not that exceeding that pressure level won't be perfectly safe, but if you keep going up, at some point it won't be.

There can be lots of difference in the data due to use of differing lots of powder, which is why we are told to start low and work up. Some other differences would include the way Hornady works up loads in a pressure barrel, then shoots them in an actual firearm for velocity. Ramshot just shoots theirs in pressure barrels. Did both use the same length of barrel? That would also make a difference.

Thanks much, that is good advice.

Let us know what your results are!

BMR: I know the question is for the DGX. But thought the following would be of some interest. Through the years I have loaded a bunch of Hornady 500gr FMJ bullets for load development. Winchester M-70, Winchester brass, Fed 215 primers, and the following three powders: 74.5gr H-335=2118fps, 75.0gr AA-2230=2224fps, and 74.0gr H-4895=2205fps. Five each of these loads were shot over the screens @ 12' and corrected to the muzzle. Altitude: 8100' and temp: 78F.
My rifle(24" bbl) seems to prefer, regardless of which bullet and powder, a velocity of 2185fps. Some combinations were a bit more accurate, but on average, the magic velocity was/is 2185fps.
Good luck with your load development.

HuntnShoot, I will definitely let you know my results.

TSIBINDI, thanks for posting your load data. I'll start a few grains below your load for AA 2230 and work up. Having the same make of rifle as yours is helpful, too. Are you able to seat to the cannelure and crimp?

...With AA-2230, and H-335, I've had no issues with seating and crimping H-4895 is a bit compressed, and requires crimping, whereas 2230 and 335 not so much.

You'd have better results with 450gr.

Phil

Are they both using the same case, same primer and same bullet?
If not there is some of your difference, the rest would be different chamber and barrel

Load to 2050 and be happy for the rest of your life.... I will tell you with absolute certainty that 2050 with a 500 grain bullet will do every thing you need to do with that rifle. Solids for little stuff. DGX for everything in between to include buffalo. solids for elephant. At 2050 you do not have to worry about ammo getting hot and locking up a rifle at the worst possible time!

Listen to “manyshots” counsel. I was involved in a project loading the 458/500gr with multiple new powders. In a 22” barrel you can safely exceed 2150. I believe we exceeded 2200.
I will tell you there is a very noticeable increase in recoil with every 50fps. Really noticeable!
Finn Aagaard wrote than at 2000 or so it will blow a bloody big hole in everything.
Go to 2050 maybe 2075 and call it good.

I note that the COAL varies between the two listings of Accurate 2230, although I don't know if that would warrant a 6 grain difference in recipes.

I would also be careful of the case length when trimming. Zealous trimming could reduce powder capacity. I would always crimp in the bullet cannelure.

I don't know if the 458 Winchester is a cartridge to hotrod. Be happy with what you get. If you are left wanting more, have barrel rechambered to 458 Lott.

BMR...you have a PM

Glad to read all this, my 500gr Partitions at 2150 and 450gr BBW #13 solids at 2200 fps should be GTG if I ever get that old Browning Safari Grade to Africa.