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.