I'm leaning towards the pistol, this is the second optic? I checked all the mounting, plate, and sight, all torqued and lock tite. Tampa-XD45, what other sites could I go to to read more on this. I looked at the DSC Gunworks site, no mention as to the reasons or benefits to welding up the chamber indicator. Have other pistols, not 1911, that have the similar notch in the barrel, and no issues.