Hi-power update

I have been participating in a “winter league” since the end of last year, but despite the name it is not a competition. I have attended most of the dates and I feel like I am making steady progress. Because of the typical Minnesota temperatures at this time of year we shoot at electronic targets from the heated 300m shooting house.

I have mostly been practicing 3 position (it’s not called that, but I forget its actual name), which involves shooting offhand (standing slow fire), sitting (crossed legs, rapid fire), and prone (both rapid and slow fire).

The standing is pretty new to me, but I think I am getting the hang of it slowly. This last weekend more of my shots were inside the 8 ring than outside, and only one missed the scoring area entirely. I even hit the 10 ring a couple of times.

Sitting is in some ways more of a struggle for me. The position is basically sitting with crossed legs and elbows on the knees. In order to get the right support I have to tuck my feet right back under my thighs which puts a lot of pressure on my ankles. I then need to hunch down over the rifle in order to be able to see through the sights. I can’t wear my shooting glasses in this position as there isn’t room for them between my face and the rear sight. In that position I have to shoot ten rounds with one magazine change within the specified time limit, which I can’t remember right now but is something like 60 or 70 seconds.

I am not very flexible and find it hard to curl up into the required position. On the days where I find the position and can hold it long enough to shoot the string, I usually hit toward the center of the target, although more often than not my shots drop down to 4 o’clock. It may have something to do with the cant I sometimes get on the rifle, but I’m not really sure. This weekend I shot one string that hit at 4 o’clock. I decided to shoot a second string and my shots were mostly in the ten ring until I had a malfunction which I couldn’t clear before the time ran out. I trimmed down my rifle’s ejector spring a while ago to keep my spent brass from leaving the state, but I trimmed it too much and occasionally a case doesn’t eject all the way and masses things up. I have a replacement spring to put in, but I keep forgetting to sit down and do it.

Prone is understandably my best position, and I usually do well. This weekend I had my best scores for a while with a 98-4x in the rapid and 198-9x in the slow fire. Pictures below. I forgot to print more scorecards, so the slow fire detail is recorded on a rapid fire card.

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Prone rapid fire-January 30th 2016

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Prone slow fire-January 30th 2016

I was quite pleased with the slow fire detail as I was using a relatively new load (24.5gr AA2520 with a Nosler 80gr HPBT). I had tried it with 24.3gr of powder, but had inconsistent results so I bumped it up a touch and it looks like it worked.

My goals for the future are to improve my offhand and sitting by practicing the positions at home in order to develop my muscle memory. I also just need to shoot more. I could also use to lose a little weight (or move it elsewhere on my body), because my jacket is getting a little tight around the middle and I don’t even want to thin about replacing that. Replacing a few beers every month with G&Ts would probably make all the difference.

My latest 3D printed butt stock is working out well with just a couple of small changes that need to be made. More details of that will come in a separate post. I have also designed and made a 3D printed hand stop with the hope of replacing the one I was using, which is on loan from a friend. I used it this weekend without issue, so things are looking good on that front.

More to come…

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Hand loading, a mishap (with no dire consequences), and finding the limits.

Since getting my new rifle I decided I had to measure my chamber so that I could accurately control the bullet jump. For slow fire with 80gr bullets I have been advised to seat the bullet 20-25 thou off the lands for best results.

I have an OAL gauge like the one in this picture:

Hornady OAL guage

This gadget works with a specially modified case that screws on the front and holds the bullet. I also own a bullet comparator which attaches to my caliper to enable me to measure a round from base to ogive instead of base to tip. Bullet tips are not consistent, but the ogive is. I decided to buy a new digital caliper that could be zeroed and give me true measurements. The comparator adds about an inch otherwise and the measurement becomes a bit abstract.

With a little experimenting and a few fails I managed to develop a technique with the gauge that gave me consistent measurements. I had read in one forum that best results could be achieved by tapping the back of the rod lightly with a piece of wood to ensure the bullet is engaged with the rifling. When I tried this my results varied more than I desired (a couple thou each way) so I settled on tapping lightly with the rod itself. This way I managed to achieve variances of less than 1 thou.

I came up with an average of 1.978 inches base to ogive using a Nosler 80gr bullet. The next step should be to subtract the required jump from this number and seat bullets to that depth, however the first time I did this I had a “brain fart” and added 20 thou instead of subtracting. I didn’t realise my mistake until I was on the way to the range. Luckily it is easier to seat bullets deeper than to pull them out and my error had no serious consequences.

In my recent efforts to load more ammunition with the 80gr bullet I have been finding it hard to get a really consistent seating depth. I have the press set up with a quality die but the bullets seating depths are varying from 1.956 – 1.961″ (my base to ogive measurement to achieve a .020″ jump is 1.958″). I don’t know if this is an error in my process, my press and die, or my calipers. I would be interested to hear any opinion on this. I have managed to reduce variation by trying to always use the same pressure and speed on the press arm, but this implies to me there is flex in the press and I didn’t think that would be likely.

A thou here or there is probably not significant in the end, but I am still curious. I know reloading can become an endless (and expensive) pursuit of consistency, the ends some shooters go to in search of accuracy blows my mind.