I am looking forload data for my Jeffery using 700 grain 50 BMG ball ammo. I can't find any info in the search function. I know RIP at one point started down this road, just wondering if anyone found a load that worked. I have a hundreds of pulled projo's from years ago, I even have a few boxes of A-Max's left. With the prices today I figured I would try loading some up as plinkers, im thinking I should be able to get close to 2100 fps, but will wait to hear from someone with more knowlegde than me, thanks

Steve

doubledown,
Maybe I am about to have a Wby Mark V 500 Jeffery, but previously ...

10 years ago I finished experimenting with a 500 A-Square, and bullets, including milsurp, up to 750 grains.
The 500 Jeffery is about 10 grains greater capacity (gross water) than the 500 A2.
The perfect accuracy load for the 500 A2 is this:

110 grains of IMR-4350, F215 primer, 460 Wby brass made by Norma, and 705-grain AAA Harlow target bullet.



The milsurp balls ought to fit the short throat of the 500 Jeffery if you seat them on the cannelure.
Try a dummy and see if it chambers without resistance.
If it does you are good to go.

I started at 100 grains of IMR-4350 using 750-grain Hornady A-Max bullets.
Have gone up to 115 grains with various bullet weights up to 750-grains.

Nothing seems better than 110 grains giving about 2050 to 2150 fps in 23" to 27" barrels with 700 to 750-grain bullets.

To start your loads, if your throat is adequate for the chosen bullet:

You might start with 105 grains of H4350 Extreme by Hodgdon and the GM215M (or F215) primer by Federal,
with your 700-grain milsurp bullet, and work up one grain at a time.

Proceed at your own risk, and kids should not do this at home.

Thanks Rip, I just needed a ballpark. The H4350 is my go to powder for the 500 Jeffery so that works out good. The 700 mil-surps chamber fine, I am going to stick with them for now and worry about the A-Max's later

Thanks again for the help, I'll give a range report when I can.