Illegal migration crisis.............of my hammer pin

[mofosheee]

Hello The High Road

Recently purchased a new lower.........assembled with a new parts kit without issue to include a Geiselle trigger. Ran two mags and noticed that the the hammer pin had migrated out of the left side of the receiver, approx 0.125".

Reviewed the Midway and Brownells online tutorials to confirm proper assembly and searched the forum for a solution. I'm not understanding the errors in my assembly and prefer not to install an anti walk kit.

Please advise.
Thank again!

 

[a5werkes]

You need to first verify the trigger / hammer pin dimensions are within standard dimensions.
You need to check the receiver apertures to make sure they are within standard dimensions.
You need to make sure the hammer spring legs are on top of the trigger pin.
Part dimensions miss-match in mfg. tolerances are the reason that a retail market exists for the "anti-walk" kit.
Post up photos of your assembly.
Illegal migration ?? Did Brandon assist your assembly?

 

[Show Me]

You need to first verify the trigger / hammer pin dimensions are within standard dimensions.
You need to check the receiver apertures to make sure they are within standard dimensions.
You need to make sure the hammer spring legs are on top of the trigger pin.
Part dimensions miss-match in mfg. tolerances are the reason that a retail market exists for the "anti-walk" kit.
Post up photos of your assembly.
Illegal migration ?? Did Brandon assist your assembly?

View attachment 1192301View attachment 1192302View attachment 1192303View attachment 1192304

Excellent post. Late night humor is good in the shop. Now, uneven preasure such as but not limited a pair of holes miss aligned will push a shaft to one side. And I think the term tolerance stacking would describe the illegal portion. Come on man.

 

[BBBBill]

You need to make sure the hammer spring legs are on top of the trigger pin.

All of what @a5werkes said, but this quote is the most common cause that I've run across when assisting others debug their home builds.

 

[Show Me]

I'll bet you put it together just fine. Simpler than a carburetor rebuild. Carb kits are like lower kits you get what you pay for. I would buy a spring and shaft. Parts from a name like your trigger is where to go even if that's how you shopped before. If you bought a cheep parts kit then an expensive trigger, lesson learned. That and stick to K.I.S.S. is the best third shift Sunday morning second job advice I can give. There will be a lot to more for you to sift through after the sun comes up.

 

[Show Me]

All of what @a5werkes said, but this quote is the most common cause that I've run across when assisting others debug their home builds.

Very good. What's simple to some is Greek to others.

 

[BBBBill]

Very good. What's simple to some is Greek to others.

True. I would not attempt to diagnose a medical problem or do surgery on someone. Some of my doctor friends can barely field strip their firearms. They express envy when I make detailed disassembly look easy and salivate over some of my builds. I tell them to just keep on doing what they do well and I won't attempt to be like them.

 

[Varminterror]

The TRIGGER pin is retained by the legs of the hammer spring - the spring leg(s) seat into a groove ~1/8” from the end of the pin.

The HAMMER pin is retained by a groove in the middle of the pin - the hammer includes a wirespring penetrating the midline of the hammer.

If your pins don’t have the center groove, or if cheap pins are used which don’t have a wide enough groove or have a finish which essentially filled the groove, OR if the spring has somehow fallen out of the hammer, then the hammer pin won’t be properly retained. A LITTLE walk is normal, just within the tolerances of the retained pins and the slack of the parts fitting in the receiver, but a true 1/8” walk can’t happen for a properly assembled trigger OR hammer pin.

 

[Bcwitt]

Yeah, what Varminterror said. If the pin can drift, it will.

 

[halfmoonclip]

With a Geissele trigger group, the pins should be a tight fit, with good grooves for the retaining springs (see Varminterror's excellent explanation).
Soooo, if your trigger pin left, either you put it together without the hammer spring correctly seated, or your lower is out of spec.
Moon