With the right powder like RL26/H1000 - high 2700s likely. Its about 50fps per inch, but will vary barrel to barrel. Plus this will be after the barrel breaks all the way in and you hit the speed up usually after 100-250 rounds.What's a realistic velocity to expect from the 156's out of a 21" tube (Seekins Havak Element) ?
That's a pretty nice velocity from a 21in barrel. Have you hit your barrel speed-up yet? It looks like with that 6in can you are duplicating a lot of 24in barrel velocities I've seen.Old thread but adding data from my recent Element load work up. I’m loading in the middle of a wide node at 57.5gr H1000 virgin ADG brass 2913 avg FPS over 10 shots and SD 10. I’m sure SD will tighten on 1x fired brass. Fed210m primers and 3.070 oal. I am shooting through a Gunwerks 6ix suppressor for what it’s worth.
Wow, that smoking along. I get 3038-3040fps from a 26in barrel verified at long range. Have you checked dope at 500+ yards on that 3000fps? I stopped trusting chronys a long time ago. ;-)I am at 3000 FPS with 57.8 h1000 out of my 24” Ridgeline, ADG brass and no pressure