Newby here with new 6CM from a good Hide member that was on sale a month or so back: 26” Schneider 1:7.5 barrel, R700, trued by Crescent (Moon), KRG X-Ray. I picked it up Tuesday, put on a March Tactical D24V42FMIL (light to go with a light rifle), and loaded Berger Hybrid 105s at 0.020” jump (using Hornady Base-to-Ogive gauge) with IMR4350 in Hornady brass prepped with a 0.271 bushing and 6mm carbide button for an OCW. Test charges started at 41.4gr stepping up in 0.2gr increments to 43.2gr. I did shoot about 20 sighting rounds at 41.2gr to zero and get a good feel and two more at each increment to look at pressure signs and continue the familiarization. Then to the OCW round robin with 4 rounds at each load. Unfortunately there were no range officers for the 200, so the 100 it was and this is what I have so far in the target pic. I ran the OCW without the Magnetospeed, and then only had two rounds at each charge left over to get MVs, so the figures in the pic are an average.
Question: do accuracy nodes open and close across a few tenths of a grain (i.e., across that loading range will there normally be juts one, two, or more nodes)? Assuming my shooting was consistent enough, it seems like 42grs might be a focus point for some seating depth testing? Would stepping up to 43, which looks to me like another node, put that much more wear and tear on the throat? Also, I could see no pressure signs except primer cratering/flattening, which was the same across all loads. Does this look acceptable to you all? I am liking this rifle!! Thanks much.
