a CONSTANT basis, for use on the 600 yd line. The primer pockets are 'loose", but if you "think" that they get 6"groups at 600 yds, by popping primers, you are VERY ignorant. They get 80 gr vld's to nearly 2800 fps,in 20" barrels, <font color=red>*</font><font color=red>*</font><font color=red>*</font><font color=red>*</font><font color=red>*</font><font color=red>*</font><font color=red>*</font>.