For loading heavy bullets ,I have read it is a preference to slow the cyclic rate ,! to reduce wear and tear on the action, and reduce recoil to keep on target better(.223+5.56) to me doesnt have much recoil, but perhaps at great distances it matters,well I see hydrolic and neumatic bolt buffers, and then theres Tubbs system, he recommends replacing the spring for his and weighting the bolt not to alter the buffer, WHO is right ?, IS any of this needed ? , Does it make a noticable difference?, I called Derrick Martin didnt get to speak to him but  asked the man on the phone,and he  said Derrick was shaking his head NO! Tubbs system looks like a pain as far as cleaning , the need to break down instead of just break open ! OKAY how about youalls wisdom and expeirence  needed here before I go on .I am loading 77gr.smk   THANKS to ALL !!

when using heavy bullets and trying to keep velocities up, pressure gets high.   adding mass keeps it locked a little longer, allowing the pressure to decrease, and allows proper extraction and brass life.  or you can run an adjustable gas block, and only allow enough gas in for the rifle to function properly.