I'm having a hard time finding reloading data for the .50 BMG.  I own an AMAC/Iver Johnson and when I purchased the gun it came with some reloading equipment.  I've decided I want to start reloading for my 50 but can't find much info.

The gun came with some Thunderbird T5070 powder that the old owner was using to reload but the limited data I've found haven't shown this powder.  If anyone knows of applications for it specifically I would love to know, but any info would be appreciated.  The recipe he was using was 250.0 grains of the T5070 behind a 647 grain Speer FMJ-BT.

Any help would be great.

I shoot an AMAC.  I have been loading 750gr AMAX over top of 217gr of 50BMG powder.Seating the bullet .010 off of the lands and getting 1.00 groups at 200yds. I'm sure the gun will do better with a little more tweaking with the load.

250 sounded high to me too.  I have found a few loads that are at or above that number but most were around 220.  I just couldn't find any with the powder that I have.

Thanks for the replys.  I will try contacting the manufacturer to see what they have to say.

Nice group Donner.  I would be completely happy if I get that kind of accuracy out of mine.

im not even sure you can fit 250 grains in a bmg shell

I easly loaded 252 grs of 50BMG behind a Barnes 600 gr. X-Bullet , which now they only make a 650 gr. !!!

250 grains is too hot for MOST bolt rifles.  I'd definitely not start there.  Might end up there but I doubt it.

750 Amax and 214 to 220 gr of H50BMG is a common long-range accuracy load.

I have a few buddies that are loading 240 to 250 grains of VV20N29 behind 800 grain solids but they are running on the ragged edge of pressure and using McBros benchrest guns setup for boreriders.

I would start out around 215 grains and work my way up 2-3 grains at a time.  When the bolt starts to get tight when you open it, reduce the charge 2 grains and consider that your max.

-David
Edgewood, NM

This test is from a chart I wrote down and I don't remember the source.

DO NOT USE THIS FOR RELOAD DATA––IT MAY BE TOO HOT!!   It's just one test somebody did comparing different surplus powders. Surplus powders

do vary in burn rate so your lot may be slower or faster burning.

CCI 35 primer
IMI 647 ball
oal 5.460
235 grains of each type powder
LC 91 brass
33.1" barrel
temp. 66-78 degrees

POWDER ––––––   AVG VELOCITY   –––––– STD. DEVIATION   ––––  PEAK PRESSURE
H5010                       –– 2991                                  ––    25                               ––     585
T5020                        –– 2979                                ––       21                               ––    609
T870                          ––2947                                    ––   15                               ––     578
T5070                      ––   2927                                  ––     14                              ––     546
H870                         ––  2921                                    ––  12                                 ––   578
WC872                      ––  2915                                  ––   28                                  ––  560
AA8600                    ––  2913                                 ––    24                                  ––   541
AA5010                    ––  2896                                   ––   22                                 ––   539
AA8700                   ––   2895                                   ––   9                                  ––    543
24N41                       ––  2867                                   ––   15                               ––     495
RVO70                     ––   2811                                 ––    40                                 ––    535
DO NOT USE FOR LOAD DATA––THIS IS JUST ONE TEST COMPARING POWDERS
  T5070 is near to WC872 from what I've read.  Since in this test T5070 gave 2927fps and that is warm as far as expected velocity from 647 bullets in a 33" barrel I'd definitely think that your load using more powder would be hazardous. Like mentioned maybe your supplier could give some input as far as load data?

I think starting at 250 would be way to high.  I started at 200gr and worked up to 233gr with the A-Max and decided on 200gr because it gave me the best group.  It was sub at 100yds and 3" at 400yds.

Just to let you guys know, I had no intention of starting at 250. I just mentioned it because that is the load the prior owner was using with that powder.  I won't be shooting further than 300 yards so I don't feel the need to squeeze extra velocity out of a round I am just beginning to load.  I was just looking for some input from those of you that have been working with the round for a while.

Thank you all for the replies and info.  One more questiion, what is the minimum powder charge for the 50 case?

Most folks start at 214 grains for 50 BMG.  I'm sure 170 grains would launch a mil-spec bullet but you'll get wicked neck smoking below 214 grains.  Probably will get to the point after a few rounds that you can't chamber a round because of all the soot in the chamber.

214 is what I consider to be the minimum load with all but spotter tracer projectiles.

-David
Edgewood, NM

make sure you do exatly as nmmi9100 says he knows everything about everything.  Reloading is a learned process, he says not to go below 214gr.  210gr in your gun might be the perfect load, 225gr might be, its mostly trial and error.  Find the best load between 200gr and 230gr of H50BMG and you will be good.

I think you should check your scale!

Hornady's sixth edition manual has several loads for their Amax. They list several powders that I'm sure would work for ya.

Check my scale?  What does that have to do with anything here?  Different loads shoot differently in all guns.  I havent been reloading that long but even I know that.  The danger associated with to small a powder charge is a real one, but you would have to be WAY less than 150gr for the bullet to not come out of the gun.