In the past I have praised Overwatch Precision for the PolyDAT which was sent to me by mistake when I ordered a gen 3 tb with a smoothed faced trigger.
This 19.4 has been seen on these forums wearing "gold". I've put most of the OEM parts back in. The trigger pin is OEM, but the slide lock (take down lever), locking block pin, and trigger housing pin are stainless version. I even swapped out the mag catch spring trying to narrow down why my magazine followers were getting passed my slide stop lever.
Unfortunately I narrowed it down to the Overwatch Precision PolyDAT, specifically the shoe itself. Apparently, it's a known issue since they updated their design to accommodate Gen 5. The shoe narrows at the top, which on my 19.4 allows enough wiggle room to cause the slide stop lever to tilt.. Under the weight of the slide and recoil spring, the slide stop lever will then push the trigger pin out about an 8th of an inch. More of my magazines would work in this scenario, but some followers were still getting passed the slide stop lever causing the slide to fail to lock back.
I tried loctite to keep the trigger pin centered. Most of my magazine followers were getting through when I did.
Having enjoyed the flat face of the shoe and the pre-travel and over travel reduction.. I decided to order an Apex Tactical trigger shoe which I installed on the polished gen 3 TB supplied with the PolyDAT using a vice, and while I think the pin could afford to go in just a bit more, I'm afraid to hit it as hard as it would take to get it to sink any further in the trigger shoe. It's at least made it through the trigger bar, and into the opposing hole on the shoe.
I kind of miss the width of the PolyDAT trigger face.. I'm digging the feel of an aluminum trigger and the trigger pull itself is great. I have one magazine that potentially has bent lips or something but all of my other magazines now seem capable of consistently locking the slide back on the final round and my trigger pin is staying put. Slide stop lever no longer has excess wiggle room.
I'm curious how the same trigger shoe would feel on the stock Gen 4 bar and how much of what I consider a huge improvement over the stock configuration can be attributed to the gen 3 trigger bar. Quite frankly I don't think it's going to get much better than it is right now while maintaining a reasonable pull weight for defensive carry as well as maintaining any internal safety mechanisms and I've had my fill of tinkering.
I meant to add somewhere that the trigger swap didn't actually make me shoot any better nor did I expect it to. Practice has. But it did add quite a bit of yum factor to this particular 19.4 and there isn't enough overtravel to cause sight movement in dry fire anymore. Sweet trigger.