Just wanted to add to this conversation with my recent experience with after-market trigger parts. I needed to swap out one or more parts for the usual 922r issues (I have the CC 7-round mag as well as the collapsible stock). I first ordered a set from Benelliparts (triggger, hammer, disconnector). It was back-ordered at the time, and it honestly took so long that I kind of forgot about it, and in the meantime, ordered a hammer from ShootingSight. Both arrived at about the same time. Having read about all the fitting issues with the polymer trigger guard, I also bought a new A&S trigger guard, so I started off switching all of the components over to the new guard.
First, I tried installing just the Benelliparts hammer, with all other components stock. Didn't work. The hammer would get caught below the notch of the disconnector, so that nothing would happen when the trigger was pulled. Next, I tried using just the Benelliparts disconnector with the stock parts. No go. Same problem, with the stock hammer getting caught under the disconnector when cocked. Next, I tried all of the Benelliparts group together. That worked. I wasn't wild about the shape of the trigger though, so I tried one more combination: the ShootingSight hammer with all of the other stock parts. Again, no go. The hammer would get caught underneath the stock disconnector.
Having taken apart the trigger group about five times at this point, I would up just putting all of stock parts on the A&S trigger guard, and it works just fine. I'm sure there are some other combos I could have tried, but I'd had enough. Looking at the components side-by-side, it's hard to see exactly where the sizing issue was, but the parts were certainly not interchangeable from a function standpoint.
