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FullClip
11-11-2010, 15:35
Finally got around to loading up some 50BMG rounds last night after saving the brass for a couple years. I used Hodgdon 50BMG powder and Hornady A-Max bullets. The Hornady book gives the recipe as 214 gr of powder with a C.O.L of 5.730 inches, but on the previous page says the max C.0.L is 5.450 inches. Figure the 5.450 inch setting is for magazine fed rounds.

The Hodgdon powder jug says 233 gr of powder with a C.O.L. of 5.450 inches.

I used 210 gr and set the C.O.L. at 5.650 inches as this cleared the press opening without having to play ‘Chinese Puzzle” to get the finished shell out of the shell holder. I checked the shell in the chamber and it drops into the AR-50 no problem, with plenty of room off the rifling. (another .20 inches if I measured a dummy test load correctly with a bullet set way out )

Anybody else use the A-Max in 50BMG out of an AR-50? Would like some any pointers. I’ve been reloading for a while, but the .50 is a whole new game to me and I don’t want to waste a lot of time and/or money getting the hang of it, or worse yet, do something that isn’t safe.


But in general, if you compare two seperate sources of published load data, and see a substantial conflict of load information, which way do you normally go?
1. Go with the higher load?
2. Go with the lower load?
3. Split the differance down the middle?

PCJim
11-11-2010, 17:25
First, I do not reload the 50cal cartridge. Given the way most reloading manuals provide their data, I would look closely at the data on the two different pages for specific differences, like bolt v semi. For pistol calibers, we do find data that is differentiated due to a short barrel, different twist, etc. If you are looking at load data for the same bullet profile/weight, I expect this is why you are seeing differing data on the two different pages.

When I come across conflicting data, I try to determine why it conflicts. Production chamber, universal receiver, barrel length, bullet profile, etc. Sometimes you cannot differentiate why. If I cannot determine why, I take the average of the two, and then use a charge somewhere between one of the starting charges and that average.

That's what I do with pistol and small caliber rifles. The 50cal is a whole different beast, and I do mean beast. If you screw it up, you can screw your life up pretty bad. I strongly suggest you approach reloading this cartridge with a very conservative attitude. It is always safer to work your way up, even if it takes a very healthy bite out of your wallet every trigger pull. But then again, you already knew that when you ventured into the 50cal arena.

Be safe!