I noticed that my hammer pin kinda sticks out slightly on the right side of the receiver. I can also push it back in, but walks out slightly to its original position (slightly sticking out) when I manually cock the hammer back. However, the pin does not walk out any further than this even after repeated manual cocking of the hammer.
Everything has been correctly installed, so I’m wondering what the issue is. The LPK is a Stag one and the lower is also a Stag.
Here are some pics:
As long as one leg of the hammer spring is on the groove of the trigger pin it won’t walk. What you’re seeing is just the tolerances of the length of the pin, where the groove is located and how wide the receiver is at that spot. I wouldn’t worry about it.
I had this happen as well and ended up replacing the pins with the KNS pin set.
have you tryed it in the other way ?
Good answer…
Take the pin out and flip it end for end. If it sticks out the opposite side then you know it’s just the pin.
Either way I wouldn’t worry about it unless it walks all the way out… then you have a problem. Otherwise, shoot the SOB… it’s not dirty enough.
Just a little FYI. The hammer pin is held in place by the “J” spring which is inside the hammer which I believe is what the original poster was talking about. The hammer spring is what secures the trigger pin in place. If the “J” spring inside the hammer gets worn out then the pin will start to walk itself out when shooting. When that happens it needs to be replaced.
I highly recommend putting quality parts in the gun. I would also ensure that you have the correct diameter pins.
Yeah, I should have more coffee in the morning before I post. You’re 100% correct I confused the two pins but have known that since about 1976. I’m pretty sure he has the correct sized pins for his Stag lower as the .172-.173" large Colt pins won’t go into the Stag without some serious force. 
The pin diameter thing is such a pain in the ass. If I remember right most Colt semi-autos are .170 in. and Milspec/ LE guns (depending on year) are .155 in. I have tried to get Bushmaster to answer me as to theirs and they blow me off. Maybe I will contact Stag and see what they say.
The LPK is Stag and is brand new. However, I replaced the trigger spring, hammer spring and disconnector with a Colt parts. The pins are .155, which are the correct diameter. The lower (Stag) is also new.
ETA: I’m thinking I may pop out the hammer pin and put it in the other way just to see if that changes anything.
If you remove the hammer pin, you will see that it is slightly tapered on the ends, and there is a groove in the center. That groove is where the “J” spring in the hammer rests in. As long as the “J” spring is good, it should not walk loose. I would simply buy another if the looks bother you. I have 600 Bushmaster carbines in my armory and almost everyone protrudes slightly.
I would email Stag Arms and ask them what diamter the pin holes are in their lower receiver. If they are larger then you will have some slop.
Well, since the hammer is new I don’t see why the “J” spring would be bad, but you never know, I guess.
In reading all of the responses, it appears that the protrusion is just a result of varying tolerances and that as long as it doesn’t move any further, everything should be just fine. I don’t really care how it looks, I just want it to be the rifle to be reliable.
One last thing: How the does the “J” spring wear (go bad) if it’s just sitting in the groove?
Well since it is new, it is probably a manufacture tolerance issue/ difference.
As for how a “J” spring goes bad. Generally if I recall it is from taking apart the lower often and from people hitting the pins in/ out. Eventually the spring gets deformed and wears out.