I've got about 90 rounds down with mine. Picked up about 10-20 fps from the first trip. I loaded up some hornady 105s with varget and starline brass. 25-27 grain in .5 grain increments. I was g2g at 26.5 and hit good pressure and 2 of 5 blown primers at 27 grains. I did have to adjust the gas...
Just got my 6mm arc put together. 20" proof steel barrel on a bcm upper for a super tight fit. Put 45 rounds in it last week. One box of hornady black and the rest were handloads ( hornady 105s and varget). Everything shot decent. Biggest 5 shot group was about 1" +/- . Best was about .5...
Old thread but good information. I have a seekins ph2 6 5 prc. About 600 rouds down it. Accuracy is fine and throat erosion is maybe a few thousandths. There is a bit of firecracking. So far all is well. Gotta be more people at or above 1500 rounds.