I have two, 525 cz and savage striker, both barrels are Sinnarms off the same reamer. Check this link to get brass, just bought 500 once fired lake city prepped/sized/deprimed $30/hundred. I shoot small gr up to 55gr, about same as my .223 in 55's.

http://www.savageshooters.com/showth...-to-20-Vartarg