Originally Posted by
GTifosi
If the tail of the hammer hits the disconnect, it can force the disconnect back onto its spring far enough to cause the disconnect not engage the hammer.
If the disconnect spring in turn is not fully up to tension/pressure rating or even a bit stiffer, and/or the disconnect is slow/gritty/binding in the trigger proper, the disconnect can remain disconnected long enough for the hammer to outrun its chance to get hooked.
Net result is the hammer rides the carrier forward and may or may not have enough ass depend on the speed it all occurs in X combination of parts to *slam fire or even just leave a small dimple on the cartridge primer.
*slam fire is really unlikely in general, or everyone would be pulling thier disconnect to get a slam fire full auto for about 30 seconds of work. It can happen of course, but its really quite rare and not something that can happen without a bunch of other magic circumstances at the same time. Or at least its never happened in the 50~60 times I've seen it deliberately tried or tried it myself over the years.
To get the hammer to hit the disconnect you've got to have some serious over gas/overpressure going on to blow the BCG back that hard to in turn shove the hammer back that stupid hard, which when taken into consideration that you said things work fine unsupressed but go to hell suppressed it sorta makes sense as putting on the suppressor will seriously ramp up gas pressures as I understand it.