Kinda depends on the guns machanisms cheaper guns have plastic parts and or bolt pins while others are metal and aluminum, Well uping your presure will ware a little harder on the O rings and springs after a wile, but these ware regardless your still going to get thousands of shots, My rubber coated marbles are about 6 grams twise that of a paintball even at nomal power of 300 psi they have stopping power. I just made some paintball darts my self they are in home made ammo 7.35 grams check em out.
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