A lot of your options will be dictated by what you can find. Brass isn’t difficult these days, I recommend Lapua or Peterson SRP, and CCI 450 / 41 / BR-4 or Fed 205M / GM205MAR for primer. 450s and 205Ms will be much cheaper than the other options with no real performance downside, but you gotta find ‘em.
For 140gr powder, H4350, Staball 6.5, or RL-16 are good choices, and IMR 4350 is acceptable as well but not ideal. Good luck finding these, but it can be done.
I have less experience with the 120s, but a reloading manual or the thread on here will have info.
For bullets, Berger are the best (the 156gr EOL is a little too heavy for 6.5CM, I wouldn’t go heavier than the Hornady 147gr ELDM), Hornady ELDM are good value if they don’t explode (there have been issues reported), and I think for general steel ringing the Hornady 140 HPBT is hard to argue with. You’ll pay double the cost of the HPBTs to run Berger LRHTs. I won’t get into hunting bullets here because I don’t care to argue about them.
Here’s the thread, it’s a sticky so it isn’t hard to find (it’s at the top of the forum you posted this in…):
Having some concerns with the initial load development with my new AIAX in 6.5CM and asking for opinions. I'm experiencing faint pressure sings (ejector swipe) with new Lapua small primer brass on every charge I've tried. Did 50 rounds, five rounds each in 0.3 grain increments from 40.0 to...
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