I brought this back ... I have a new gun Glock 31 in 357sig . Shot 117 rounds Sunday and after the .3rd Mag it started working very well on various types of Ammo.
Upper limit on powder charge is 9.4gr of 800x with a 125gr projectile. Also Sig SD Ammo does not cycle well, it’s hot !
Speer 125gr FP cycle well as do Hornady 125xtp.
Did not take any 140gr Sierras.
Shot 2 Mags of converted 40S&W cases and they worked flawlessly!