Speaking of casting!

For the .300 GNR I like the heavy nose to allow more capacity in the case. I personally didn't have as much luck with LilGun as I did H110/296. Some did well with AA#9 too. 4227 was good, just a little slower.

Lee has a 113 gr. mould for the .30 Carbine that is really great IF you can find one. You can also "size down" many .311 bullets to .309" in a LEE sizer, even jacketed.

I also modded some moulds by cutting the tops out of them. I did a 150 gr. with limited success, making a 120 with a long nose. I use the lube groove as a gas check shank. It can be sanded or reamed to fit perfectly. I did make a great 215 gr. .375 bullet for some GNR applications as well as cut down the big .51 cal. bullets to suit the .510 GNR revolver. The 450 made a grand 410 gr. FNGC and the 500 was cut from 375 t0 325 grs in several plain base and gas check styles. Back when you could get a double cavity LEE mould with handles for $20-25!

I used the .510 GNR and a 410 gr. modded buffalo gun projectile to take a small Bison at HHC. Mimic of Gary's experiences published in his book the bullet zipped through both sides (three times, two shoulder shots and one neck finisher) like hot butter at a moderate 1050 -1100 fps. You don't need to get crazy throwing a one ounce slug!

I also took sheep with the .300 GNR at HHC. I highly suggest a HP or expanding bullet for that application. The .30 cal is a small bore and unless you get some hydraulic energy transfer it just pokes holes. Not as humane. To do it again I'd probably use a XTP Hornady 100 gr. Ditto for Whitetails. I'm also glad I DID NOT try it on hogs. I was a little over excited about realistic demands on the great little round.