Alloy for a 300 Rem Ultra Mag

miestro_jerry wrote: I was thjink of a 200gr bullet pushed to about 2000fps. This would be for Elk hunting.

Jerry

My old friend the late Greg Kalnitzky had quite a bit of experience using cast loads at full power in the .375 H&H and the general parameters which worked for him should give you something to work with.

Linotype, driven hard, tends to “crumble” and the bullets shatter, giving poor penetration.  It would be much better to use wheelweights and then heat treat them to get enough hardness to stand the additional velocity and pressure.

If you want a solid bullet which does not expand, use straight wheelweights, run them at a rate which produces uniformly frosted and well filled out bullets and quench these in water directly from the mould.  They will harden to about 24-28 BHN, depending upon the thermal mass of the projectile and the effectiveness of your quench.

For an expanding bullet use a dilute alloy of 1 pound of wheelweights to five pounds of plumber's lead, cast the bullets, sight cull and heat treat separately in the oven ay 475 degs. F for six to eight hours, then  water quench.  This will give a ductile alloy of about 18-20 BHN in a .30 cal. 200-gr. which will stand .30-40 Krag velocities with decent accuracy for the number of rounds you would shoot in hunting.   I use such loads for deer hunting with good results, but have not killed anything larger with them.   Personally, I'd like to see you use something bigger than a .30 cal. with cast bullets for elk.  Anything which will heave a 250-gr. bullet over 2000 f.p.s. should do fine.

Bullets should be lubed without sizing and gaschecks should be applied and crimped after heat treating, using a sizing die which is large enough not to size the bullet.  A hard lube such as Rooster HVR will work fine.  To provide some lubrication on long bore-riding noses, tumble bullets after filling the grooves, in Rooster Jacket or Lee Liquid Alox.  You can use full jacketed charges with slower powders which will fill the case to 85% or more of load density.   Greg used IMR4350 with 320-gr. cast bullets at about 2200 in the .375 and used them to kill eland, kudu, warthog, waterbuck and zebra, as well as smaller game.

If you look up in back issues of American Rifleman there was an article by George Martin in the 1980s entitled “Cast Bullets In Africa” in which the author used similar loads.