Bought a bunch at Knob Creek last year from Blue Sky Surplus, and promptly lost the data sheet... It was listed as being "for .223, .308 and .30-06" and appeared to be only "fair" for those cartridges - Seemed a little on the slow side. It's a long skinny stick. I'd like to give it a shot in a 6BR, and maybe a .22-250 or .243.