Tuesday, August 29, 2006

Range day,

and a new toy tool

No, not a boomstick, a chronograph. I'd been thinking about one for a long time, and finally broke down and bought the basic Chrony model. It doesn't crunch the numbers for you, it just gives you the velocity of whatever flies over it. When I first got it I could only think of one way to test it, so I set it up in the back yard and fired an airsoft pistol over it. I now know the pellets range around 275-290fps six feet from the muzzle.

I wanted to make sure the 8mm I fixed up years ago was sighted in so if I get to go bambi-whacking deer hunting it'll be on, and I don't want to try to fit in with all the people who'll wait to the last minute. On that part, if I miss I can't blame the rifle, it was putting everything right where it was supposed to. Load I worked up was 49 grains of IMR4064 pushing a 150grain Hornady soft-point. I only ran four rounds of it over the Chrony and got 2558, 2576, 2648 and 2582fps. I haven't studied this enough to make any judgements; according to the Lyman loading manual that's indicating well under "STOP!" pressure levels, and that's 2 grains below the listed max. At this point I won't jack with the load, it gives 1" or better groups at 100 yards and if current velocity won't take a deer they've migrated from Krypton.

Took the K31 along, and this is why I think everyone should have one. I loaded six rounds, sat down at the bench and fired them- no special care, just line up and squeeze- and got this














Military surplus ammo and a standard issue rifle. Don't you love it?

I'm not used to using the Chrony so instead of getting a string of ten I only recorded eight. Low of 2502, high of 2585 for a spread of 83fps and average of 2553.

With the M1, I had some of the Korean 1970's ball. It's always shot well, so I wondered how consistent it was. Out of eight rounds, low of 2545, high of 2762 for a spread of 217fps, average of 2674. Much less consistent than the Swiss 7.5x55 ammo, which might explain why I'd sometimes get a really good group, then so-so to terrible compared to the good one. It's great practice ammo, and without question it'd take care of business in a fight, but it ain't near match quality. I need to get some suitable bullets and do some handloading for the M1 and see what I get. I thought I'd thrown in a bandolier of the Greek HXP I got from CMP, but I didn't so that'll have to be tested later. I've consistently had good results from it, so it'll be interesting to see how consistent it is.

I tried it with some .22 ammo, Federal Champion and Eley Sport from the Martini model 12.
The Federal gave a low 1173, high 1236; next lowest was 1203. Eley lowest 1062 to 1124- you noticed the difference in that one, sharper crack- with the next highest being 1096. Comparing them:

Federal Eley

1236 1096
1173 1092
1203 1068
1225 1098
1203 1124
1220 1095
1203 1062
1207 1075
1206 1075
1222 1089

I'll have to learn more about breaking these numbers down to mean something. And I promise not to do a lot of number-listing in the future, but it's my toy tool and I'm enjoying playing with learning to use it.

Last thing was a surprise. Aguila makes some .22s they call 'Sniper Subsonic'. It's a long 60grain bullet with a short case to make it fit standard chambers.





Here is a live round and fired case compared to a standard .22LR.







How useful it is is very dependant on your rifle; that long, heavy bullet is not stabilized by many barrels. I've got one rifle that shoots it fairly well, another from which every second or third round keyholes at 25 yards. I'd never tried them in the Martini, so tried one shot at 50 yards. Nice neat hole around three inches lower than the Eley. Tried a second and it almost went through the same hole. Ok, that's interesting thinks I. So I dug out the Chrony I'd just put away(this was the last shooting for the day) and set it up, and fired ten rounds for velocity, then a few more for fun, getting this:














I hadn't even set up a target for this, just spotted an unused corner of an old one. Not counting the low-left(called flyer) that's 1.25" on a target I can't center with iron sights as well as a black bull. Velocity ran
880
862
884
855
894
889
887
869
891
889
for a spread of only 39fps. It ran around 200fps slower than the Eley, around 300 slower than the Federal. Just out of curiosity I moved back to a 100-yard bench, raised the sights same as I would for the Eley and fired two. Two because I thought I'd had the partial box and another full one with me. Oh no, just the one, so only two shots at 100. Not enough for a real test, but they did stike cleanly, no keyholing, and just under 2" apart. I need to take this stuff back out and try it again in this rifle.

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