Hi Danny Boy -
With due respect to Jackfish's comments, I've been reloading for over 40 years & never damaged a gun w/high pressure loads (I have BLOWN one up, but w/the wrong powder & lack of attention, NOT high pressure loading). :oops:
So, NOT TO SAY ONE CAN'T - there's high pressure & there's excessive pressure.
My point is that , watching for the standard signs of head expansion, primer flattening, sticky extraction, etc., WHATEVER PRESSURE your loads generate that don't overstep THOSE BOUNDS is SAFE IN YOUR GUN!!
Individual guns of a type don't vary much in pressure handling ability, and SAMMI specs are intended to be SAFE in any gun in good condition, but they're NOT necessarily ultimate loads!
Questions of "Why 'overload'?" aside, if you want all you can safely get (for whatever reasons please you), don't be afraid to find what YOUR GUN can do for you.
Simply use proper caution in evaluating the results of your testing. :wink:
Regards,