False Start.

So, before the FTW Ranch trip, I tried to get a start on putting the Glock 39 through the whole 2,000 round rigamarole. The gun seemed pretty clean, with only the soot from the first fifty rounds I'd fired in it. I put a new recoil spring assembly in the gun prophylactically, added a drop of Lucas Oil to all the factory-specified lube points, and went to the range with fifty rounds of S&B 230gr FMJ and fifty of Speer Lawman 185gr FMJ.

Something was definitely off. The gun experienced one failure-to-feed and three failures to fire, the latter all showing a light, off-center primer strike. Normally this would be the sign of an extremely filthy gun with an old recoil spring, but the gun was clean and sported a brand new RSA. Another possibility would be a too-tight extractor, so I scrubbed the area between the claw and the breechface with a toothbrush and then checked extractor travel and tension. It looked good.

I went back the next day with a hundred rounds of the Sellier & Bellot and experienced ten of the light, off-center FTFs over the course of the range session: One round in ten. Something was definitely wrong.

I PM'ed a Facebook friend who works at Glock and asked for some suggestions. In addition to the Armorer's Manual suggestions of "Clean Gun, Replace Recoil Spring", he noted that I might want to detail strip the slide and make sure everything looked good in there, and try a different trigger bar as well.

I just so happened to have the complete trigger assembly from my Glock 37 handy, since it was currently sporting a ZEV trigger, so I tore the little 39 down to have a look inside and swap the trigger while I was in there.
 

The tar-like sludge in the striker channel can't be helping. Did the previous owner not know to not lube that shit?

Me: "Jesus, all the small parts are tacky...the slide lock, the firing pin safety, the striker spring...feel like they've been lubricated with the Pepsi and popcorn butter from a theater floor. I mean, look at this trigger bar... Here's the trigger bar that came out of my G37 after the 2,000 round test. It's kinda gray and sooty, but it hasn't been cleaned. Now here's the trigger bar from the G39. It's covered in a sticky layer of black cack, and I guarantee it hasn't fired no 2,000 rounds. It's like the gun's been lubricated with..."

RX: "Crisco. Congealed vegetable oil."

Me: *eyes widening* "Holy shit you're right." *spins chair to keyboard*

It was exactly like you see on guns that have been stored a long time with the plant-based oils on them, and they'd gotten that stuff on every small part in the gun. They would hardly be tackier to the touch if someone had spilled a Coke in there. In the picture above, the trigger bar I'm holding is the one that came out of the 39: That buildup of soot and cack is from ~250 rounds of shooting. The gray trigger bar in the gun now is the one that came out of my G37 after 2,000 rounds. It hasn't been cleaned, other than whatever fingers have knocked off it from handling.

I'm going to hit the gun with some synthetic-safe Gun Scrubber to degrease it good, re-lube it properly, and then we'll start shooting it for realz, yo.
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