What .300blk molds should I get?

[bangbangping]

Bangbangping do you also think that sizing the bullets to .311 is the correct size for .300blk?

Yep, that's what I use. Also size the neck of the brass a little larger than you would for a jacketed bullet.
Lots of options there, but I use the Lee Universal Neck Expander body...
https://www.midwayusa.com/product/14046 ... anding-die

...with a stepped expander like this in it:
http://noebulletmolds.com/NV/product_in ... ts_id=1118

[popper]

Accurate 31-142C. PB for powder coating. Runs 2100 fps in BO carbine and works just as well in 10" 1:8 pistol. Needs COWW heat treated alloy for that fps. Feeds fine. planning on hi-tek coating I'd go PC instead, cheaper, faster, easier (HV is tougher to get with HiTek) and works great. I use 31-168C PB and 31-184C GC ranchdog style in the pistol for pigs. They feed good from Lancer mags. I size 3085 but the pistol barrel is a cheap KAK that works fine, haven't tried 309 yet. I do have a box or 2 of 220 factory ammo, don't use subs. The boat tail on the Lee 220 needs to GO.