Low temps = Large groups

On New Year’s eve I ventured out to the ranges at Minneapolis Rifle Club to do some shooting (well I wasn’t going there to crochet was I).

I had hoped to get in some practice on the small bore range and then do some comparative load testing for the Swing, as well as test a hand load for my new handgun. In the end I realized that I should have just stuck to the small bore. Ideally I would have gone to the range the day after boxing day as it was the warmest day that week, but since we had people staying and had planned a couple of nights away over the weekend, New Year’s eve was the only day I had free.

I left my house just after 9am accompanied by my friend from school, Beth. I had preheated the truck so it was relatively comfortable for the journey, but unfortunately no one had preheated the roads and I nearly came a cropper on a slip road just minutes after setting off. Fortunately I managed to keep it on the road and away from other vehicles, and once I had rediscovered traction and a heart rate approaching normal I proceeded with a little bit more caution. The rest of the journey was pleasantly uneventful.

The small bore shooting house was already on the way to warming up when we arrived, and after a little while we were able to begin in relative comfort. I had remembered my full fingered glove and a blanket to put under my mat for extra padding and so the problems were limited to a little numbness in my right hand from the cold air coming through the shutter. This made effective trigger control increasingly difficult to achieve as the shoot went on, but regardless I came away with some half decent groups (see picture below).

50 meter small bore target. Dec 31st 2013

50 meter small bore target. Dec 31st 2013

Considering this is only the second time I have shot small bore since I came to the US, I am quite satisfied.

Shooting small bore. Dec 31st 2013

Shooting small bore. Dec 31st 2013

New Year's eve small bore shoot.

New Year’s eve small bore shoot.

I finally found a good reason to grow a beard.

After shooting small-bore I decided to go over to the general purpose range to test some .308win loads.

I intended to compare three loads: my standard long range load comprising 46gr N-140 behind a 155gr Sierra Match King seated to 2.850 inches. My new 300m Special load of 40gr N-140 behind the same 155gr SMK also seated to 2.850 inches. And the 300m Special load but with the bullet seated 15 thou from the lands (I recently invested in an OAL gauge). I have all sorts of questions in my mind about the performances of these loads that I can’t answer effectively in competition conditions.

Unfortunately these questions were not going to get answered that day. The temperature was down around zero Fahrenheit and although I was well bundled up it wasn’t long before I was feeling it. My first shot knocked the snow off the roof of the shelter, which was entertaining, but then I was unable to group better than about 2-3 inches. Considering I was shooting at 100yds it readily became apparent that no useful data was going to be accrued that day, so we moved on to load testing for the Glock. I won’t go into detail except to say that the load still needs a tweak.

Below is a photo of me shooting my Glock. Well bundled but I still managed to hit the paper.

Handgun load testing Dec 31st 2013

Handgun load testing Dec 31st 2013

I will return to the range on a warmer day to test those loads. Results will follow.

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Reloading for 300m

I have been shooting at the Minneapolis Rifle Club for about a year, most of that being on the 300m range. I have been using my Swing rifle (.308win) with hand loaded ammunition.

The usual format of a 300m competition is 3×20 shot strings + sighters, which when you consider that my handload recipe was intended to keep a 155gr match bullet supersonic at 1000yds, means I have been getting pretty sore.

I have made adjustments to my position and swapped my handstop out for an old smallbore one that was a bit more ergonomic, but I always ended up counting down the rounds till I could put the rifle down. This does not make for accurate shooting.

To counter this I decided to try a new recipe for my 300m shoots. I based it upon the recipe I was given for my hunting ammunition by Charles Young, which he referred to as the ‘Tweed Valley Special’, and since I have achieved half minute groups with it out of my hunting rifle using soft point hunting bullets I thought it could be a good starting point. I have named the new experimental load the ‘300m Special’ for my records.

The hunting recipe requires 40gr of VV-N140 behind a 150gr Hornady interlock, which I seated to 2.80 inches OAL. I tried to seat them out to the same depth as my match ammunition (2.850 inches) but the 150gr soft point is a shorter bullet than the 155gr match and so I was uncomfortable with how little of the bearing surface of the bullet was actually inside the neck of the case.

For my experimental 300m load I simply duplicated this charge with a match bullet (Sierra Match King) seated to my usual match OAL of 2.850 inches.

The day I tried it out the temperature was close to zero Fahrenheit and there was a light snow falling.

I used a full fingered glove since although we shoot from inside a heated building my left hand is usually very close to the small window I shoot through, and my finger tips have in the past gone numb in very cold weather. I also added padding under my shooting mat as it is intended for use on grass and as such has no padding to protect my left elbow which has been getting quite sore. This all helped to improve my comfort.

When I shot the new ammunition I estimated a 5 minute elevation adjustment compared to the previous load, this proved spot on and both my initial sighters were in the 10 ring. The recoil was mild enough that I got through a full 20 shot string without serious discomfort.

The light snow made for a very useful wind indicator, and in my first two strings I recorded very satisfying scores. However in my third string I suffered as a result of the mirage caused by the warm air inside the building meeting the cold air outside, this made it very hard to get a clean sight picture. I don’t know why this only really bothered me in the third string when it must have been present all along.

Nevertheless, at the end of my detail I had the highest score of the prone shooters (there was a second detail to follow and I have yet to see the results so I cannot at this point declare victory), and I was not suffering the effects of strong recoil as I had previously.

The only hesitation I have is that although there were only light winds and I was consistently hitting the 10 ring, my shots were not well grouped. I am aware that although the recipe this load was derived from is very accurate, a different bullet, seating depth, and rifle means nothing is a given and the recipe might need to be tweaked for best performance. In view of this I will be returning to the range in the next couple of weeks to do some load testing under more controlled conditions, and with a borrowed chronograph to measure velocities.