Re: 6.5x47 lapua
Matt,
Since WnRoscoe built our rifles last year, Matchking and I have done allot of work with this caliber. Not more than some others, but perhaps more than some others chose to share with us. I hate re-inventing the wheel so I believe in sharing information. This is some of mine.
Some guy in Colorado published a test in an attractive article, but the test was inconclusive and less than exhaustive as to what I believe a new round test should be. That tester mentioned blowing primers. The problem for me is at Colorado altitudes/air density, the occasional blown primer is "an every blown primer" here at humid 90F sea level air density. I suspect those blown primers were caused by the same large firing pin hole in the bolt face of his and my commercial sniper rifle that originally blew primers in my early tests; cup extrusion breaking off into the firing pin hole.
Another shooter in Tennessee on 6mmbr.com did some benchrest tests and published his reports too. That shooter's match load was 39.3 RL15, 120, 3k+fps, but that charge was too hot for my rig. His test was like the Colorado test. He did not write about conducting long range accuracy tests, nor tests at varying altitudes and most importantly, varying degrees of ambient temperatures. I've been testing mine for a year from 38F to 98F.
My experience was similar to Matchking's and Seth's: RL-15 was ambient temperature sensitive. Although exciting at first, RL-17 velocities varied across a broader range from morning to afternoon firings than did RL-15. I wish 17 had worked well, but it did not in my gun in NW Louisiana this Summer. One may consider using a different powder for every season, or every 10F change, or a morning load and an afternoon load, but that's dang sure more than I want to do though benchresters may find that way smart.
H4350 has been the SECOND most stable powder across various ambient temperatures among the favorite propellants I tried for this round - in my test experience, in this case: 6.5x47L with 120 and 130's. Note Matchking's VV test too.
HVarget has been THE most stable powder across various ambient temperatures, in my tests here, and at matches in Stephenville, Waco, and Kingsville, TX. Don't know about "no where else cause I ain't shot it no where else."
Your bullet choice will depend on your barrel twist. Ours are 8's. They shoot all the bullets well (120, 30, 40 grainers). Having about 2 grains less capacity than 260Rem., some believe 6.5x47 case capacity tends to favor 120-30 grain bullets. The gun will shoot these bullets well if its built right. Flip a coin among the top performing bullets and develop a load with it, or get ChadTRG to do that for you.
We can't tell where you are from the absence of your profile so we don't know your atmospheric variables or altitude. CCI#41 primers are what I use. Rem 7 1/2 Benchrests, and WLR shot good too.
COAL will be around 2.7" but the bullet choice and chamber dimension will determine that measurement. Start at the lands and go back on the seating after finding your accurate powder charge starting at 36.0 Varget and going up to the node of around 2850 and another at 2950mvfps firing either a 120(123) or 130 bullet. To me, upon Rich Emmons' suggestion, the 130 is the more versatile tactical sport bullet due to its superior long range exterior ballistic performance.
This book helped me and I recommend it to all my friends:
Handloading for Competition by Zediker.
These shooters help me and I recommend them to you as watched users:
Rich Emmons, WnRoscoe, ChadTRG, 4Rail_Gunner, Matchking, to name a few.
I went out on a limb for ya; be careful.