For anyone interested in .260 Rem, I think I've finally found a solution to forming decent quality .260 Remington cases.

I've tried just about everything out there for getting quality cases, including:
  • - Standard Rem cases - highly irregular weights and neck wall thicknesses - I turned these, but to get them uniform I had really thin necks and the primer pockets expanded faster than I would have liked
    - Necked up .243 Lapua cases - these worked really well for 2-3 firings, then I started getting donuts and accuracy went to he!!. I may try these again if I can get the donuts cut out (I have the tooling)
    - Factory Nosler cases - these worked fairly well, but had thin necks to start with - I turned them to clean them up which made really thin necks (like 12 thou); otherwise, they were decent cases, but I'd get higher runout from them on some of the cases when F/L sizing
    - Necked down 308 Lapua cases - good strong uniform cases, but with really short necks (the parent cases were 2.013" average)

    The solution: I just finished up a set of necked down 7mm-08 Norma cases. This was pretty unifrom brass to start with and the necking down from .284 to .264 caused no inordinate runout. Neck wall thikness averaged a little over 14 thou, and I did a light turning, leaving me with a 13.75 thou neck. These cases appear to have Lapua or better quality, with drilled flash holes. Weights for the 40 have 1.2 grain total spread (about 1/2 a percent of average weight), so no weight sorting will be required. I have them trimmed to 2.030". The finished cases have <1 thou TIR on the necks.

    I have my 260 back together again after swapping actions, putting a new SSS stock on it and bedding. WIll rework my standard load of H4831sc and 123 gr Lapua Scenar&#39;s and give a report after I shoot it this weekend. Barrel is a 28" LW.
    Elkbane