Consistency.

Went to MCF&G yesterday morning to do some chrono work. I had a pistol along for a forthcoming Shooting Illustrated article, as well as the Glock 20. I was meaning to chrono some of the 180gr Remington FMJ I got from Lucky Gunner as well as some Federal American Eagle 180gr FMJ I'd purchased at Indy Arms Company. Unfortunately, I forgot the Remington at home, so the only ten mike-mike that got measured yesterday was the American Eagle.

I'll do the Remington on Thursday, because today and tomorrow are supposed to be much like Monday was: 90°F/90% humidity, and that's indoor shooting weather as far as I'm concerned. The humidity down there on the banks of Eagle Creek will take the starch right out of you.

The American Eagle 10mm has a reputation for being ".40 S&W power level", which isn't entirely true, as it's 50-100fps hotter than pretty much any 180gr .40 I've chrono'ed, but it is definitely the mildest 10mm load I've yet clocked.

It's also the most consistent. Freakily consistent...

The first string of ten had velocities so close together that I shot a second one just to see how much of a fluke it was. The second string had one round that was, at 1,011fps, about a dozen fps slower than the next slowest round in the string, and that opened up the standard deviation to a hair over 7 feet per second, which is still astounding.

Here's the better of the two strings:

LO: 1020
HI: 1033
AV: 1028
ES: 13.42
SD: 3.87

I spent the remaining thirty rounds shooting the steel plates from the 20 yard line. Even with the never-to-be-sufficiently-damned factory sights and the factory Glock trigger, it was stupid easy.

There was one failure to fire on round number forty-six of the day (#1,376 of the test). The round went off on the second try. It looks a little like the gun may have been slightly out of battery, but I could not make it replicate the situation in dry fire? Besides...

...even the good primer hits are well off-center in the G-lock.

This makes 1380 rounds since the Glock 20 was cleaned or lubricated, with four failures to feed (#401, #454, #1,213, #1,297) and four failures to fire (#598, #1,016, #1,029, #1,376). 620 rounds to go.
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