I'm loading 140 Matchkings with H4350 using Hornady brass and getting 2772 average. I hit some mild heavy bolt lift when at 2840 range (.6 grn over my current load) so I backed it down to that node to have a temp swing safety belt
With pressure signs in mind, my go to is any velocities which exceed twice the speed of sound and extreme spread is in the single digits is a winner. Shoot the old us sniper ammo was about 2500 fps and look what they could do. So super high velocities equate to less dial up, but it's not the be all to end all. Modern artillery ammunition clocks just about the speed of sound and some cases less than depending on the charge weight
You might want to lower it a bit as well with temperature swings. As in, if you test during the winter and you are getting high velocities, it’s going to change during summer time and that fps will start to rise. Which most likely will result in pressure signs showing and higher velocities than recently chronographed during your winter load workup.
I’m getting 2810 FPS right now with 140 match burners, some pressure signs were showing at 1920 so I backed down. It’s not uncommon to see 6.5 140’s with upwards of 2900 FPS.
I'm loading 140 Matchkings with H4350 using Hornady brass and getting 2772 average. I hit some mild heavy bolt lift when at 2840 range (.6 grn over my current load) so I backed it down to that node to have a temp swing safety belt
With pressure signs in mind, my go to is any velocities which exceed twice the speed of sound and extreme spread is in the single digits is a winner. Shoot the old us sniper ammo was about 2500 fps and look what they could do. So super high velocities equate to less dial up, but it's not the be all to end all. Modern artillery ammunition clocks just about the speed of sound and some cases less than depending on the charge weight
My 6.5 CM with a 28" barrel is just a little over 2700 fps. shooting the 140 gr. ELD loads. No pressure signs during the hot summer.
You might want to lower it a bit as well with temperature swings. As in, if you test during the winter and you are getting high velocities, it’s going to change during summer time and that fps will start to rise. Which most likely will result in pressure signs showing and higher velocities than recently chronographed during your winter load workup.
I’m getting 2810 FPS right now with 140 match burners, some pressure signs were showing at 1920 so I backed down. It’s not uncommon to see 6.5 140’s with upwards of 2900 FPS.