I put the 14 lb trigger return spring (the lightest of the 3 that came in the kit) and had to stone the main spring around the hooked end slightly for fitting, but otherwise just polished up the "moving" surfaces a bit. ( by hand, no Dremel butchering or anything close to being abusive).
Trigger pull is fantastic in DA but ignition is only 4-5 rounds per moon clip. Other rounds the primers are dimpled pretty well but no ignition.
Brownells offers 40 S&W moon clips in the .42" thickness (normal is .40") supposedly to address this but it is only for the smaller frame 646.
I am shooting my IPSC 40 loads, 200 Gr FMJTC, 175 power factor, Winchester primers. This has been very reliable for years in a variety of pistols. Alas, it worked well in the 610 too prior to the Wolfe springs.
I'd like to enhance the "lawyer trigger" that came in the gun to make it a little more competition friendly. Looking for suggestions.....
The way the factory used to teach it at armorer's schools is to file the mainspring strain screw, always keeping it tight against the spring when checking the DA pull weright. (work on the cheapest part). The use of moon clips has always required a bit more "ummph" from the hammer fall than when using cartridges that don't need them. The clips require more clearence between the shield at the rear of the cylinder (on the frame) and also bounce around some, thus soaking up a bit of the hammer fall. The .45acp guns are well known for this, and I have no reason to beleve that the 10mm / .40's are any different. The old time serious wheelgunners sometimes actually cut three coils off of a standard return spring and ADD them to the standard one, making the trigger return faster. Remember that the trigger return spring has almost nothing to do with the DA pull...if you are getting DA misfires it is most likely because your hammer tension is too light or, maybe, the firing pin potrusion (sp?) is a bit short, etc. Have you cut the spur off of the hammer? That will lighten it and can cause issues as well.
Sorry for the late reply...got caught up in an emergency response situation at work for the past few days.
I have not cut off the hammer spur and do not intend to.
Also, I got to measuring rims on my brass. The rounds that did not go off seem to be on the thin side.
Also had a guy tell me I needed to switch from Winchester to Federal primers.
I think I'll try some new virgin brass and Federal primers and see if that helps....
Appreciate any input.