In trying to put a pair of Rock River 2-stage NM triggers in a pair of Spikes lowers which I received, the trigger and hammer pins DO NOT fit.  Even with much more significant pounding than a trigger pin should take, they don't go in at all.  They do fit into my Essential Arms receiver.





Looking around, I see reference to the RRA 2-stage needing oversized 0.156" pins, and that they don't work with 0.154" pins.  Is that correct - would the 0.002 make a difference?  If that is the case, what steps should I take to fit the pins to the receiver?  My next door neighbor owns a machine shop, and would probably be happy to bore the holes out 2 thousandths... but I'd like input from those in the know before I take that big of hammer to the problem.

 

2 stage shoud use the same size pins. my spikes and rra 2 stage went together very nicely. ask badassar15 in spikes industry forum about the hole sizes.

The standard pin is .154" + .0015".  A .156" would be oversize to save the likes of you and me from the cost of replacing the lower.  Use the .154"
458

The plot thickens....





I can't, for the life of me, find my digital calipers.  But I did find that the shank of a 5/32" drill bit will fit snuglybut acceptably through the holes.    Since that's a hair over 0.156", it would seem that the pins  might be to blame, and could be quite oversized.  I'll have to find my caliper, or borrow one, and measure them.

 

Which of the lowers does your drill rod fit through?  Use the .156" pins in that one.
458

Through the Spike's.  But the pins won't fit, they seem noticeably larger than the 5/32" drill rod.  I'll get accurate measurements tomorrow or Monday.  



 

Last update:  The pins won't even fit through the HAMMER.  It looks like I definitely need some new pins!

 Look at the hammer, on the front of it is a 'J' pin. Think spring.  That engages the groove on the pin.  If you look through the hole you will see it towards the front.  This is why your pins will not go through the hammer.  Bet they go part way.  The hole in the hammer is > .156 on 3 hammers  just measured.  Try to press the pin through the hammer while not in the lower.

 If the .154 pins fit into the lowers you'll be fine.  I think you're getting hung up on the resistance of the 'J' pin, and maybe not having the disconnector aligned.  Make a slave pin out of a standard pin or a #23 drill .154".
458

It took some very significant pounding to get it into the hammer even part way, not even to the J-pin.  These pins are just huge.   I've put a couple of RRA 2-stages together before, and this is NOT how the pins were.





On a good note, I remembered that I have a field repair kit, and grabbed the pins from it - everything went together like it should.