Posted by Iowegan back in 2004.
Here's a slightly different twist that doesn't require welding. This is for a NM SBH so the hammer plunger measurement will be different for a NM BH.
Remove the hammer plunger. Use a shank from a 3/32" drill bit or drill rod and duplicate the cutout for the locking pin. The TOP of the plunger should be exactly like the factory plunger. The BOTTOM of the cutout will extend .085" longer. The factory cutout is .185" long and the replacement cutout is .270" long. The factory plunger length is .750", the replacement plunger is .835". The factory plunger will extend .300" from the hammer. The replacement plunger will extend .385" from the hammer.
With the replacement plunger installed, the longer plunger extension will hold the cylinder latch down longer in the timing cycle. The latch will release just as the stop enters the leade. Cylinder latches could vary in thickness so yours might be a few thousandths shorter or longer. I've done three NMBHs using this technique and they all worked perfect with the above measurements.
I have found that the hammers have some variance on where the retaining pin is located in the hammer so this measurement can effect the proper length of the plunger.
Just remembered you may have to drill the hole in the hammer deeper for the plunger to have full travel.
Dana