the bullet on the right is a .510 dia , 535gr ... mess maker.
I'd done the 458 SOCOM necked up to 50 cal before for some subsonic rifle projects.
When my bullet guy showed me this , it set me to thinking AR15.

'got a barrel spun up , dug out the old die set , waiting on the bullets (he makes them 1 by 1 on a large hand press).
KAK shipped me these 420 gr bullets to play with til the mess makers arrive



more soon.