Many thanks
Griff
As far as lighter bullets shooting better, I suspect the barrel time of the lighter projectiles hit a "node" in the harmonics of the barrel, whereas the loads with the heavier bullets are in-between "nodes". A node being the point where the barrel stops moving in one direction, and starts to go back to where it came from (and is therefore not moving). If you could find a barrel time that hit a node with the heavier bullets, they'd likely do as well. Try much faster (or slower) powders if you can't hit it with the powder you have tried.
I was playing with the PPC the other day, and with the same brass, bullets and primers, one powder produced 1.3 average groups, while a change to another powder resulted in sub .4" groups. It's all about good vibrations. HTH, Dutch.
Mike
Shoots sub moa 115 gr partitions---won't shoot 100 or 120 gr.
Varmints only Bergers 110 gr----
It refuses to shoot anything with a boat tail or less weight than the 100 gr XLC---------at 3" high 100yd
1 " high at 300-------3" low at 400