The rifle is for 6.5x47 Lapua, shooting 130 grain bergers (or maybe 123 gr Scenars) in Lapua cases through a 28.5 inch barrel. Based on multiple earlier tuning tests optimal parameters (tightest group) are (1) touchpoint + 0.002" for bullet seating depth, (2) 41.0 gr of H4350 for the Berger 130's, and (3) N540 38.0gr for the Scenar 123s. This barrel likes to shoot dirty better than frequent cleaning; can go through 50+ rounds and retains precision. Use Use CCI No 450 SR primers. For the test below I will use Berger 130 gr bullets.
Here's the question. For each separate barrel tuning test I have done so far on this barrel, I have only used one powder type (which I think most reloaders do). I am thinking of running one fairly large tuning test using multiple different powders to see which powder and charge for that powder is optimal; this will require the usual incremental (I use 0.3 gr increments) series of powder charges for each different powder, except for H4350 which we know the optimal charge for. For this test I plan to use Berger 130s as before. The intent is to test/tune at 250 yds to find the optimal powder/charge for 1000 yd target shooting.
Since this is a fairly long barrel (28.5"), I am wondering if I should select a fairly broad range of powders (relatively slow to fast within a reasonable range for this barrel) for this test to find the optimal powder. Presently I have the following powders: N540, N550, H4350, RL15 (about 1/3 pound left), and IMR 4064. Recognizing some powders are not presently commercially available, which powders do you think I should select or (try to) buy to test a broad range (relatively slow to fast for this particular barrel). I would also like to hear your thoughts on the incremental charges for each powder given the above information. All comments are welcome.
Here's the question. For each separate barrel tuning test I have done so far on this barrel, I have only used one powder type (which I think most reloaders do). I am thinking of running one fairly large tuning test using multiple different powders to see which powder and charge for that powder is optimal; this will require the usual incremental (I use 0.3 gr increments) series of powder charges for each different powder, except for H4350 which we know the optimal charge for. For this test I plan to use Berger 130s as before. The intent is to test/tune at 250 yds to find the optimal powder/charge for 1000 yd target shooting.
Since this is a fairly long barrel (28.5"), I am wondering if I should select a fairly broad range of powders (relatively slow to fast within a reasonable range for this barrel) for this test to find the optimal powder. Presently I have the following powders: N540, N550, H4350, RL15 (about 1/3 pound left), and IMR 4064. Recognizing some powders are not presently commercially available, which powders do you think I should select or (try to) buy to test a broad range (relatively slow to fast for this particular barrel). I would also like to hear your thoughts on the incremental charges for each powder given the above information. All comments are welcome.
