u/Kromulent

I have the 3-position AZR-15A1 in a PSA 10"/H3 that works fine, except for the full-send-on-semi thing, which it does 100% of the time. The hammer is not hitting the gizmo, all the springs are put in correctly, and with one exception as described below, it works perfectly on the bench.

Specifically, with the selector on semi, cycle the action, pull the trigger, click!, keep holding the trigger down, pull the charging handle all the way back and then ease the action closed, and it works perfectly - trigger resets normally when you release it and everybody is happy in normal semi-auto mode.

Do the same thing, but this time, lock the action open with the bolt catch. Keep holding the trigger down, release bolt catch, bolt slams home and now the hammer follows it. You have a 'dead trigger', as you'd expect, until you cycle the action again. This reproduces the full-send problem.

Furthermore, if you don't use the bolt catch and just release the charging handle from the fully-rearward position with your fingertips, you get exactly the same result.

Now here's the interesting part.

If you do the same thing, pull the charging handle all the way back, but let it come forward about a quarter inch and then release it, it works nicely again! I see two possibilities:

1: It's not caused by the bolt slamming home, whatever is happening is happening in that first quarter-inch of travel.

2: It is caused by the bolt slamming home, but only if the bolt slams home with 100% force.

I'm inclined to dismiss option 2, because stripping a live round from the magazine probably has to slow the bolt at least as much as losing that quarter-inch of travel does.

This is an interesting observation but I have no idea what to make of it. What's happening in that first quarter-inch?

made this stuff way back, and thoughtfully wrote the dosage on the bottle

there was about 1/4 the liquid it started with, the rest evaporated away. that means what's left is 4x as strong. i took that into account and drew up a nice dose, put a few drops on a teaspoon of sugar and dried it out in a warm oven

i dont think it's degraded a bit, it's wonderful

https://cornfirearsenal.com/ goes nowhere