Re: 260 brass question
If you want to purchase factory brass, Norma, Rem, and Nosler make it. It you want to form it, you can neck down 7mm-08 Win brass with a 260 die. This works well. You can also neck up any 243 brass. I would not recommend necking down 308 brass, since the necks will become very thick (unless you plan to use a custom bushing size to account for this)I personally use Rem factory brass, and it shoots great. If you plan on using it for match shooting, you have to remember you will only be able to retreive about half to maybe 75% of your cases. I don't want to waste the money and time when I will lose the expensive high-end cases and/or size formed cases. I don't think your rifle will be able to tell the difference from the high-end brass to the Rem factory brass when a proper load is worked up. I know mine doesn't. My $.02.