Day at the Range

Discussion in 'Long Range Hunting & Shooting' started by liltank, Jan 9, 2010.

  1. liltank

    liltank Well-Known Member

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    Nov 3, 2008
    Wed. was a cold blustery day in Central PA. We were set up in a field trying to ring some steel. It was about 21 degrees with a head on of 10-15mph winds at the bench and 8-10 with 10-15mph gusts left to right at the target. It took me about 15 shots to walk it in to the steel. 22.25MOA up and 6.5MOA to the left put me on and was able to ring it consistently with my little 18" custom. I was using 48grns RL17 with a velocity avg. of 2612fps. They were up and down with about a 30fps spread. It was very difficult to figure out the right wind velocity at the target.

    When it was warmer the spread is more like 15 to 20 fps. The RL17 is very temp sensitive. Anyway with those click values put us at a LRF distance of 695 yards +/- 5 due to conditions. We had some empty helium tanks that we hit right around 705 to 710yrds. I could really tell the speed variance at this distance. Some would drop short, some over, and a few dead on the target. All in all, this was the most successful shooting outing I have had to date with a .308 at long range. I do have a couple of hits at 1060, but that was with my 300WSM and it was not consistent at all.

    My cousin with his Lapua had hits all day long. He only missed when aiming at the Helium tanks. Well at least we thought we had missed. The were passing through the back of the tank and thought we were shooting high. Oh well, lessons learned.

    Tank
     
  2. MontanaRifleman

    MontanaRifleman Well-Known Member

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    May 21, 2008
    Interesting report Tank.

    I'm not sure I would blame the powder for being temp sensitive. It may be, but it might also be the chrony. I have had simalar experiences using H4350, H1000 and Retumbo which are all supposed to be stable powders. What I notice is my Chrony will give different readings as the sun changes it's angle and hieght in the sky as well as occoasional clod cover. When a cloud hides the sun or the chrony gets covered by the shade there is an immediate change in reading with the same loads at the same temps. The same thing happens as the sun moves across the sky with little change in temp and a more gradual change in readings. This is my expereince with both of my chronys.

    Just something to think about.

    Mark
     

  3. liltank

    liltank Well-Known Member

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    Thanks Mark, that's good to here. I do notice that if I go to my one local range at 1:30 to 3:00 PM, I can get consistent readings on partially sunny or sunny days because the shadow stays the same. When we try to chrony on cloudy days and in an open field, our chrony gives erratic readings. So I might be closer than what I reported.

    Tank