gamestalker
member
I did up a batch of some 7mm RM and as always I use my RCBS scale that is older than dirt, and also as usual I seat my rounds up close and personal to the lands. Using some necked mixed head stamp brass that is probably on it's 12 or 13 th session and a hefty charge of RL22 to push the 139 gr. Hornady BT's, I was astonished at the consistent velocities I was getting. In the past I've usually maintained a 20-30 fps +/- velocities, which isn't outside the norm nor an issue, in my experience. But these rounds were within 3 fps of each other of 10 rounds fired.
The only thing I did any different was I got maticulous about my seating depth. Normally I'll get them touching and then back off .010" and groups are tight. But this batch I actually put them on the lands, so I'm assuming this was the factor that brought the fps spread together and increased the average velocity a tad bit. Nothing else changed, all the brass was looking great, no resistent extractions, but my average veloctiy went up by about 30 fps, average was 3450 fps - 3453 fps. I honestly didn't think it was possible to achieve consistency to that degree.
The only thing I did any different was I got maticulous about my seating depth. Normally I'll get them touching and then back off .010" and groups are tight. But this batch I actually put them on the lands, so I'm assuming this was the factor that brought the fps spread together and increased the average velocity a tad bit. Nothing else changed, all the brass was looking great, no resistent extractions, but my average veloctiy went up by about 30 fps, average was 3450 fps - 3453 fps. I honestly didn't think it was possible to achieve consistency to that degree.