Update: I was testing recoil springs when I my P-10F doubled. This is after about 1500 rounds, two matches, and a lot of dryfire with this setup. At first I thought I had inadvertently bump-fired the light trigger, but it started happening even after pinning the trigger to the rear. This was with my heavily modified trigger group and the CGW 10320 striker and one of the heavier recoil springs I was testing. I think the slight radius/angle cut at the tip of the striker leg, coupled with the extra forward slide velocity and my light striker/trigger springs, was bumping the trigger bar down instead of catching it and pulling it forward. The tip was still sharp, as was the sear, and I had a full 0.050" of sear engagement. I think the problem is my rear insert. The holes in the polymer frame are elongated and allow the insert to move vertically a few thousandths of an inch. Hard reloads were pushing the rounds up into the ejector. (which has broken twice now) I've since cut my replacement ejector to prevent future contact, but the movement is still there. I'm going to re-drill the insert and frame holes for 2.5mm roll pins to remove the slop, but I decided to go ahead and modify the striker. I mounted the striker in the endmill and recut the leg to 92 degrees, just enough to remove the radius and flatten the leg. Then a full stone/polish taking care to keep the tip sharp and even. I didn't cut it to 90 degrees since that's already the OEM angle, I just wanted to land conservatively between OEM and what looked to me like a 5-6 degree angle on the 10320. The break increased from 2lb 14oz to 3lb 2oz. The oem profiled 10300 originally broke at 3lbs 5oz.
This is not an indictment of CGW's striker. Obviously my trigger setup is way outside the normal operating tolerances so I'm not surprised the striker started misbehaving.
Not sure if related, but I modified a rear slide plate with a screw to prevent the striker from travelling far back enough to release from the trigger bar. It lets my dry-fire 95% of the trigger stroke without the break so I don't have to keep cycling the slide on multiple target drills. Unlike holding the slide slightly out of battery, it doesn't reduce the trigger weight. But unlike traditional dry-fire where the sear surface only slides down the striker leg, I wonder if the down and then up motion of the trigger bar wore the striker leg in some weird way.
