I just looked closely at my pistol. The inside of the trigger bar is dragging on "wire looking thing" (technical term) shown in post 13 of @PX4 Storm Tracker's thread (LINK). I think this part may be the hammer pin spring. That's my best guess based on a low resolution version of the Tekmat exploded drawing.
Last edited by pangloss; 04-14-2018 at 09:19 PM.
You're right. That is the hammer pin spring. By the sound of the squeak one can often guess what thickness of metal is rubbing which. That spring is a frequent culprit. If you notice in post #23 of https://pistol-forum.com/showthread....on-usage/page3 the part of the trigger bar that rubs against the frame by it is getting a lot of friction. This would make for 2 more spots to lubricate.Originally Posted by pangloss
I'm thinking friction on the hammer pin spring may be my culprit too.
Wondering if folks are describing that as normal because:
a) it's part of the design.
or
b) it's something that frequently needs attention.
If it's a) I guess I just need to lube it?
If it's b) what do you recommend as a fix?
Given that the wear from trigger bar v. frame seems inevitable, the "2 spots to lube" comment has me leaning towards "it's also supposed to rub on the hammer pin spring." Am I reading that wrong?
I wonder if that spring is fully seated in the pin, and not pressed down a bit where it would rub/catch the trigger bar.
Back to that picture, linked above. EL's TJIAB, which is part of what I based lubrication points for my other guns, lubes/greases the tension pin for the spring tails (you did put that spring in polished side towards the cup I hope), as well as in between the sear and the hammer. I actually asked him in another thread about lube on the hammer pin, and didn't receive a reply, so I have put some on one of my guns for my next range trip, which I hope Tuesday will be (if not it may be a while as spring projects/house painting is going to take up free time).
You can push down that spring, there by pushing out the top pin, via the back side (backstrap side) of the gun. See EL's hammer replacement video, for about the best video to be able to understand.
Last night in a dream, made me come back and read both your threads, as my brain was saying you said you ordered a PX4"c" and I wasn't sure if you ordered a normal gun and tried to put a TYPE C parts in it, or you ordered the compact. The trigger bars are different between those.
Normal is a relative term. Normal might mean that most Compacts do that. It does not prove that it is acceptable. Perhaps Beretta has a run of trigger bars that are different or frame casting issues.I'm thinking friction on the hammer pin spring may be my culprit too.
Wondering if folks are describing that as normal because:
a) it's part of the design.
or
b) it's something that frequently needs attention.
If it's a) I guess I just need to lube it?
If it's b) what do you recommend as a fix?
Given that the wear from trigger bar v. frame seems inevitable, the "2 spots to lube" comment has me leaning towards "it's also supposed to rub on the hammer pin spring." Am I reading that wrong?
The design is good. We have over 90,000 rounds on PX4s and so little trouble from hammer pin springs. However, here’s one thing I’ve noticed: Often when cleaning in front of the rear right frame rail, behind the trigger bar, folks will insert a rag or patch and unknowingly push the top bar of the spring downward. The top leg drags on the hammer assembly and could stay down, changing its position. After cleaning I like to take a small skewer or punch and hook the top bar of it and snug it upward.
I have had to replace 2 hammer pin springs because of loosening. The indication was a hammer pin drifting, but never a problem like you are experiencing.
Tugging up on it gently and lubricating it and the other side of the trigger bar might help. If the spring stays down it might need replacement.
It will rub on the spring a little, that is normal. But, something is forcing your trigger bar to drop down, that is not right. Only the slide or right safety lever should do that. https://pistol-forum.com/showthread....l=1#post704616 posts 19-22
Yes. The Hammer pin spring, the wire looking thing, rubs on the trigger mechanism making a squeak. All 5 of my old PX4s did this.
Additionally, according to your videos, the trigger bar is not dropping down on double action because the hammer's double action hook is maintaining pressure on it.
Also your video indicating the pressure you need to finish pushing the trigger forward is not much. This would indicate a small rubbing or deflection not caused by a heavy immobile part.
The trigger bar dragging against the frame is normal and it’s more pronounced when new. You don’t notice it in live fire. The squeak is abnormal.
Bob Loblaw lobs law bombs
In your experience, did the trigger bar rubbing the hammer pin spring ever result in any problems? It's a little annoying, but I don't see how it really hurts anything. However, I'm new to the platform, so I don't put much stock in my opinion on the matter.
In live fire I didn't notice it.
The highest round count I got to was a shade under 30k on a single 9mm full size. This issue got a little bit less pronounced versus the newer pistols I had at the time. So there is some 'wear-in' that can mitigate the issue but only about 25%.
The other data point that made me realize it wasn't a huge issue was it persisted across multiple caliber lines and different years. I had 3 9mm full size, 0.40, and 0.45 all from different years and they all did it.
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