Hey Shawn, if I might? I have been a LE armorer since S&W was still making it's metal frame pistols, even before the 1st of their polymer pistols was intoduced. Been thru several Armorers classes from S&W since that time. To include even the hated SIGMA pistol. Originally the SIGMA had much a better trigger pull back then. When S&W scrapped the 1st SIGMA's and brought them back as the SW VE series, the State of Mass changed the law on them, and the gun had to be built with a 10lb trigger pull. And no, I don't remember the lawsuit with Glock(which was settled out of Court, IIRC) being the reason for the trigger change. The lock work in a SIGMA is NOT similiar to a Glock, period. I might be mistaken about that, but I don't believe so.
Anyway, what I was told about the "tampon" was that it was put in the trigger return spring to dampen the vibrations that were occuring in the spring, while the pistol was firing. In a few rare instances, the early SIGMA springs would sometimes fracture at the hook bend. S&W investigated the problem, and the Engineers decided to put in the "Tampon", as a vibration snubber. That worked, and works well still. However, several things come to mind. In the past 20 years or so, being around lots of SIGMA's(God love 'em...lol!), M&P's, and SD's, both in LE and civilian hands, I have yet to see one break. I have also yet to see any trigger return spring missing the "tampon", although I would wager that someone, somewhere has probably lost or removed theirs. Another point is that spring technology and manufacturing has advanced greatly in the last 20 years. Materials and heat treating are much improved, making springs almost(almost, but not quite) indestructable.
Oh, and one other point. They don't talk about it, but I know for a fact that in very rare cases, Glock trigger return springs break as well. And not knocking Glock, either. I like them very much, I just don't like the trigger pull on 'em. Just personal preference. Glocks trigger springs are almost identical to S&W's and suffer the same vibrations. Glock considers it a very small problem.
end result is this, rest assured that trigger return spring breakage in M&P's and Glocks is almost a non issue. And even if it happens, it's an easy fix that anyone can do. If in the field and it occurs, your trigger finger, or a support finger can be used to push the trigger forward and the weapon's trigger will reset. Not the best solution, but a workable expediant fix until the problem can be addressed.
Just don't worry about it, it's not a problem.
Also, rest easy knowing I was not trying to call you down in anyway, I just thought I would relate my experience over the years with lots of rounds down range. For your perusal, if you like.
Thanx, my Brother,
Ofc.JL
