Re: Can I start load development with new brass?
The same load might be 1/2gr off, maybe, in the fireformed brass later but not too far if so.
I checked for that on a load of mine too and .5gr more powder in the fireformed brass resulted in the same large groups as was observed during load initial development. Groups went from under 1moa to over 4moa in .5gr, so over a .5gr jump, in my book, may leave a good load undiscovered.
That said, I don't think that load will be very tolerant in other than the testing conditions it was first fired under.
I have found several loads to tolerate a full 1-2gr swing in charge wt. before opening up measurably, these are the best, at least the most usefull up here where temp swings are big. We can compensate for a velocity change but the group size has to hold. In this particular case, a .5gr drop produced over 2moa groups as well, so it's a fine line with this one.
I shoot the 308 quite a bit too. I've heard more than a few times that fliers were because of the GM210M primers and CCI BR-2's solved some of these issues. I switched to the BR-2 for a while but haven't tested strictly for this yet. 165gr Gamekings over 44gr Varget at 2.85" and 180 Scirocco over 43grs are great loads in a couple rifles we have. IMR 4064 has given me some outstanding new groups with the GK bullets lately, maybe even better than Varget.
[ 05-16-2002: Message edited by: Brent ]