Wednesday, July 27, 2016

Range Day

Rode with Mike Grasso out to Atlanta Conservation Club to do some chrono work and get some groups shot for a magazine article.

First thing I wanted to do was chrono some of that Prvi Partisan .357SIG to see if it was as variable as the muzzle blast & flash led me to believe...
LO: 1314
HI: 1367
AV: 1340
ES: 52.43
SD: 16.18
Well, not as bad as I feared, but still the most wildly variable of all the .357SIG FMJ I've chrono'ed out of that gun.

Then it was on to the main event: Four different 10mm loads from the Glock 20. The first up was Prvi Partisan's 170gr FMJ offering:
LO: 1020
HI: 1087
AV: 1049
ES: 66.58
SD: 19.84
So, like most commercial 10mm FMJ offerings, basically it offers another fifty to a hundred feet-per-second over a hot .40 S&W load.

On to the jacketed hollow point offerings...

I had some Hornady XTPs in both 155gr...
LO: 1290
HI: 1321
AV: 1306
ES: 30.70
SD: 11.31
...and 180gr flavors:
LO: 1109
HI: 1127
AV: 1118
ES: 17.78
SD: 6.32
That ten shot string of 180gr XTP, by the way, is the second most consistent that I've ever chrono'ed, bested only by another Hornady offering, the .45ACP 220gr +P Critical Duty out of my CCA 1911.

Last up was the 180gr V-crown JHP from Sig Sauer's new ammo division. Sig has 10mm offerings in both the P220 and 1911 platforms, and someone at Sig must be a fan of the caliber because they're loading theirs pretty spicy, the way 10mm was meant to be. I was interested to see how close the measured velocity out of a 4.6" Glock 20 barrel would come to matching the box-flap claim of 1250fps, presumably from a 5" test barrel.

I was also interested in seeing how consistent the ammo was, which is generally a pretty good indicator of QC.  The results:
LO: 1158
HI: 1215
AV: 1168
ES: 57.46
SD: 16.88
Nine rounds were all clustered within about fifteen FPS, with that one 1200fps outlier blowing the average. Still, not bad.

We shot up the remainder of the box of Prvi Partisan FMJ which, combined with the three chrono strings of JHP made a round count of eighty for the day through the Glock 20. All eighty rounds cycled normally and there were no malfunctions of any kind to report.

This makes 230 rounds since the Glock 20 was cleaned or lubricated. 1770 rounds to go.

After all the range work it was time for lunch.

A ham & brie sandwich and potato salad at Rail Epicurean Market in Westfield, washed down with some sweet tea.

AK usage yesterday: 0.
Day rating: Good.