I have a Raptor .257 HP which I believe was setup and tested by Scott(motorhead) when he was bailing them out.
It's a 100 yard hole puncher and I have not had any problems with it or shot it lately.
.257 JSAR Raptor HP Slug
.357 Evanix REX, AEA Terminator
.30 Mrod from .25, AEA HP SS
.25 Rainstorm II, DAR I, Hatsun Bullboss
.22 Prod, Venom, 2240/2250, CP-1 & CP-2, MK II
.22 Varminter, Liberty, Gauntlet, Avenger, DAR II, LCS SK-19
.177 FAS 6004, SIG P320, BEE P17, Colt Peacemaker, Alfa Proj
.177 Sig Sauer MCX (CO2)/(HPA), AF Edge, Wildfire, Webley
.177 Crosman MK II
Vintage: MK II(.177), 78G(.22), 101(.22)