To keep this thread going as a source of knowledge, I got my barrel back and did some pressure testing. With the 365gr SB2s at 10 thou off the lands my COAL is 4.446…it's obviously setup to maximize case capacity etc. so take that for what it's worth before trying anything that I'm about to post. My starting points were 2gr below what quickload said was max for the 350gr SMK and then I worked up from there.
Tried RL16, N565, N570, and H50bmg.
98gr N565 gave 2730fps and would be absolute max that I would consider loading. Probably real hard on brass. Ejector, little sticky bolt lift, little bolt click. 97gr was 2690fps. Slight ejector mark, slight resistance with bolt lift. Probably a much more reasonable max.
103gr N570 shot 2740 w/o pressure (no ejector, bolt popped right open, easy extraction) but I couldn't fit anymore in the case by simply pouring it in via the funnel….when I got home, I used an electronic toothbrush to vibrate the case and was able to get 106gr in without affecting my seating depth so I'll see if I pressure out between 103–>106 tomorrow. If I throated it out a little and seated out further then I could get a little more but if I pressure out that won't be necessary.
87gr RL16 was 2730. Same pressure signs as 98gr N565
107gr H50bmg was 2560. No pressure. However, it was definitely compressed and no more room whatsoever. Also, was obviously slow.
N570 looks the most promising. Should break 2750 and maybe 2800. We'll see tomorrow. I'd be really happy with either. Both RL16 and N565 aren't bad either, especially if my barrel speeds up a little. 2700fps w/ a G1 BC of 1.01 does pretty well. Push comes to shove I might try the 350gr ICBM2. Would pick up a little velocity just not sure how much.
