So I was trying to work up a load with h4350 and 139gr scenar. 40g was flat horizontal group 40.5 was this pic. 41g blew out two out of five primers and went back to flat horizontal group. Would you try dropping to 38 and working up?
6.5cm ar issue
- Thread starter Beladran
- Start date
Your chrono is showing 2830 fps. What does your rig typically get with factory ammo near this weight range?
Reason I ask, is it would typically be roughly about 2700 fps from a 24" test bbl.
It takes a significant increase in energy/pressure to account for an extra 130 fps, not to mention this is a gas gun with what appears to be a shorter than 24" bbl.
All of which says you should back off the charge to get your velocity down to reasonable level so that your assumed pressure would also be reasonable. Good Luck and in for the range reports.
Reason I ask, is it would typically be roughly about 2700 fps from a 24" test bbl.
It takes a significant increase in energy/pressure to account for an extra 130 fps, not to mention this is a gas gun with what appears to be a shorter than 24" bbl.
All of which says you should back off the charge to get your velocity down to reasonable level so that your assumed pressure would also be reasonable. Good Luck and in for the range reports.
