Ok, so I went to the range today to test my first ground up build and it worked pretty well, but the one thing that was annoying was some trigger slap!  I'd heard of this with cheap U.S. made AK triggers, but never with an AR.  Also, the FCG I used came out a well used Colt SP1 that I put thousands of rounds through with no such issue.  I'm not sure what factors are relevant, but as I said, Colt used SP1 FCG, Colt M16 bolt and carrier, Noveske N4 lower, CMT upper.  LMK if you need more info.  Thanks!!!

Josh

found one f-up on my part -- hammer spring was backwards, which also explains the walking pins and light primer strikes with failures to fire.

would this cause the trigger slap too?

Is the safety the same one you were using before ?? Weird prob

rj

it is a new safety selector (RRA star type), and yes, they are all small hole components.  thanks.

Seperate the upper and lower.  Carefully drop the hammer [ hammer drop block is good, otherwise control it with your thumb. You are probably familiar with this ]. Now keep holding the trigger back and recock the hammer.

Does the hammer slide under the safety sear relatively easily  or does it kick the trigger?    If it seems to kick the trigger try the colt safety in place of the RRA safety.

Is the safety sear spring in the trigger with the large coil down ?

Remember, inanimate objects are not out to get you .  You just have a little mystery here to solve.  Have you smashed your trigger finger with a hammer recently and it's just real sensitive and you are feeling the safety sear engage

rj

no kick and the coil is right.  no smashed fingers yet, but it's early!  LOL!

i suspect getting that hammer spring right may fix the problem -- only one way to find out though!  

Put the upper back on and try the same test. Drop the hammer, hold the trigger to the rear and cycle the bolt with the CH. Does the trigger kick back now ?  If so something is different in the bolt carrier / hammer face geometry on this new combo.

I asked about the safety because I was thinking that maybe the RRA safety allowed the safety sear to travel upward slightly more than the original colt safety.

rj

i was following you on the safety thing -- it was a good thought.  just tried your test with the assembled gun and no kick, etc.

the gun passed the function check and everything fine before going to the range.  i think it was just that the pin was walking out and causing the alignment of the parts to be bad.  i hope it's straightened out now.

Mr. Magic says;
Things double checked rarely go astray.

rj