I am shooting some test loads tomorrow - 270 Win loaded with 4 different 130gr bullets, but the same powder charge, primer, etc. I have 5 cartridges per bullet, so 20 rounds total. I was planning on shooting four, 5 shot groups - one group for each bullet. But I have contemplated shooting four, 4 shot groups, of each bullet, and then one composite 4 shot group - one with each bullet. Just to see what happens with group size with mixed bullets. I guess I will decide after I have shot the 4 shot groups and see if there are any "screamers" that need that fifth shot.