HI mate the H&N 4.3mm/4.4mm copper coated lead BB's perform very good in the SAA's I used them in mine and in those guns they give slightly better accuracy then the umarex zinc coated steel BBs, and the low ricochet is a bonus.. The webley accu BB's are the same as the H&N smart shot copper coated lead BB's just in a different tin. I have those too they are 0.1mm larger ranging mostly at 4.4mm but still work great as they are the same size as the umarex/asg steel BBs..
I have done a chrono test using both BB's on my YouTube channel if you want to see it and the fps etc the SAA's give out when using both types of BB's..
ATB Marc
Some of my favourite guns in. You collection, Umarex Beretta 92fs - Colt Custom 1911 - Walther Lever Action - TM Hi-Capa Custom Build Project - Colt SAA .45 & many more..