This is a two part discussion regarding Sig Sauer P938 trigger questions I have. The first part is subjective because I am considering replacing the original plastic trigger with a stainless steel one from Sig P938/238 Skeletonized Stainless Trigger - W Engineering USA . The 18 reviews are almost too glowing regarding how much the stainless steel trigger improved the performance of their pistols. So, has anybody else “upgraded” their P238/P938 plastic triggers to metal, and is it as amazing as the reviews depict it?
The second part of discussion is why I am considering changing to a metal trigger. My pistol has begun exhibiting a two stage trigger reset. I have trouble shot it down to either the roll pin holding the trigger bar in the trigger has deformed, or the hole in the trigger bar has wallowed out, or the holes in the plastic trigger have wallowed out. I am suspecting the roll pin has deformed. I will have to remove the trigger to determine which one of the culprits is causing the problem. Since it appears pressing the trigger pin out of the frame is going to be a pain in the butt, I’d like to just do this once. I seriously doubt the plastic trigger is the problem – thus the first question.
For anyone interested, keep reading and I will explain the anomaly. The trigger bar is basically an L-shaped piece of metal with the top of the “L” connected to the trigger via a roll pin on the “front” end. The bottom of the “L” presses the ejector and the sear to the rear simultaneously. The pressing of the ejector releases the firing pin safety block. The pressing of the sear releases the hammer. The two stage reset I am experiencing is the trigger bar is able to rotate (due to one of the three potential causes discussed above) in such a way that it resets on the sear first, and the second part of the reset is the ejector. Therefore, if the trigger is not fully reset, then the hammer can be released by pulling the trigger, but the firing pin block remains in place, which means no bang! The magazine limits the amount of trigger bar rotation, but it really rotates a lot when troubleshooting without the magazine in place.
I installed an aftermarket trigger in my p938 Scorpion a few years ago. The new shoe looks and feels good and helped with pre-travel a bit but I wouldn’t call it a major performance upgrade. I’ve done nearly a dozen triggers on various personal pistols and I recall the p938 being one of the top two frustrating ones for me. I suggest having access to a hydraulic press for the pin you referenced above. I did not and it was truly a “pain in the butt”. Good luck!
I took the trigger out today. I quickly concluded the tap it out approach wasn’t cutting it As I have no hydraulic press, I put a Wheeler gun punch in a drill press. Here’s how that worked out:
I changed to a nail set and had greater success Thinking through it now I would probably use a vise instead. Regardless, nothing seems to be glaringly wrong:
So, I called W Engineering. The guy there was very helpful and didn’t put any sales pitch on me at all. He said the main culprit he has heard about is changing the grip panels can affect the clearance gap for the trigger bar between the grip panel and magazine. I do indeed have aftermarket grips.
Between him spending so much time with me, a cold call non-customer and the pain in the butt pin removal, I ordered his aluminum aftermarket trigger
I will reevaluate the grip panel situation after the new trigger gets here.
I bent a couple of punches during the process as well. Getting the pin back in was just as much (if not more) of a struggle for me.
I replaced a trigger on my FN509 a while back which had a similarly stubborn press fit trigger pin. The new trigger (Apex) came with a nice machined jig with guide punch holes that made the removal/install of that pin so much easier. It’s basically a fancy pin punch/armorer’s block.
There are a number of armorer bench blocks out there, but since you have a drill press, you could easily make something similar out of a small block of aluminum or other type scrap with hole guides that fit the diameter you need. It would help you keep your punch secure and stable while you bang away and reduce risk of cosmetic damage. Single, sharp hits on these types of pins are more effective than multiple repetitive taps. Also, make sure that your work surface is hard and without give (think concrete floor or steel surface instead of wooden workbench).
Got some time to install the W Engineering black anodized aluminum trigger today. Despite only expecting it to provide esthetic improvements to an otherwise fairly unattractive pistol, it actually fixed the reset issue I was concerned about. I believe the slot the trigger bar slides into has spread outside design tolerance on the original “plastic” trigger. These photos compare the old to the new slot feature:
Once reassembled, the reset works perfect because the thinner slot on the new trigger restricts the rotation of the trigger bar in the X axis without restricting the rotation in the Y axis. Trigger pull weight measurements before and after are identical, ~ 5 lbs. It is rationally unexplainable, but like many reviewers have said, the trigger pull “feels” lighter. Take up is about the same, but over travel is definitely reduced. Back to the esthetics:
As I have no hydraulic press, I put a Wheeler gun punch in a drill press. Here’s how that worked out:
