In my Smith I run 21.5 of H110, and seat the bullet in the rearward cannelure, this is the 300 xtp. I have used the same load on the 320 gas check lead bullet, but man the xtp, works as advertised. 4" groups at 100 yrds with a 5" pistol, I will take that all day long, and it is not as violent as the 180grn pills at max.
Tab, no dice, the Ruger cylinder is stronger, from a guy who does not own a Ruger revolver, I have owned them but only blackhawks and always just sold them. well I did own a Redhawk once, not my cup of tea.
Now, as to Ruger DA frames being stronger, when rebarreling revolvers, the only frame I ever bent, was a security six, good thing was just rotate it the other way and it will bend back and line right back up.