Horsemen61, I don't know how to post a link to another thread so I just posted below. Would love to hear how you experience is going, has not been as much chatter around this caliber as I originally thought there would be, seems to be one of the better reloaders rounds.
I checked my first attempt at subsonic 180gr XTP in the 350 legend. I resized these to 0.356 for this test. Trail Boss is the only powder I had on hand that I felt comfortable testing. Using an OAL of 2.195 with Hornady brass. I started with 7.0 gr Trail Boss about 80% case fill. Avg. velocity was 816fps with extreme spread of 111fps. Accuracy was very poor @ 2.2" 50 yards.
I will up the powder charge to 7.8gr about 90% case fill and see how accuracy looks. I will look for TinStar as well but need to get idea where to start first.
I then tried 170gr Hornady Interlock bullets, these did much better. I used H110 with an OAL of 2.225", all I had was federal AR small rifle primers so that is what I used, winchester brass.
25gr H110 - around 2100 to 2200fps, I accidentally deleted the data from my chronograph. Accuracy was okay with a 3 shot group of 0.88" @ 50 yards.
25.5gr H110 - Avg. 2218fps, ES 100fps, 1.28" group @ 50 yards (2 touching 1 flyer)
26gr H110 - Avg. 2223fps, ES 71.4fps, 0.62" group @ 50 yes (cluster group)
26.5gr H110 - Avg. 2339fps, ES 118fps, 0.60" group @ 50 yds ( vertical group).
