I recently tested my zinc 223 Rem loads.
As I posted above I sized the bullets to .224.
I shot them out of a HK SL6 which has about a 11" twist rate and polygonal rifling.
Accuracy was horrible, shot at 50m dispersion was about 30 cm. Some bullets even tumbling and hitting sideways.
I don't have the possibility to chrony my loads at the moment, but the balistic software calculates a muzzle velocity of about 1090 m/s.
To test wether the polygonal rifling has something to do with this stabilizing problem, I shot the same loads out of my recently acquired swedish Mauser Frankenrifle with a enormous match barrel chambered in 223 Rem. Accuracy was marginally better 20-25cm and no keyholing.
But still this is nowhere near acceptable accuracy.
I'm thinking about sizing to .225 or bigger and try again.
What do you guys think?
Thanks in advance for your help.
David
PS: here's the link to my original ZINC bullets post
http://castboolits.gunloads.com/show...highlight=Zinc