Wow, that's fast. I don't think I get those speeds with LVR @26ish grains. Usually in the low 2,700s like your other loads.For those loading long with windowed mags, what kind of velocity and loads are you working with? I ran my regular gasser loads for initial testing and break in and had my 16” Shaw portless barrel around the 2700-2725 range with 77 tmk. Loaded a pressure ladder with Lever yesterday at 2.350” and 25.4-26.6 went 2802-2927 which is smokin! Big jump in velocity from 26-26.3 grains indicating possible pressure but no other signs.
I windowed my first mag a couple weeks ago and have some of @KyleR1985 s LVR loads worked up I'll try to test today.