yes and no...it should be standard...Bob is starting from a barrel blank and has to cut the chamber anyways... so might as well cut the leade at the same time...Sadly Crosman and Spa and probably some others do not bother and just leave square edged rifling and only cut a chamber... do not really understand why...see pics in post # 2 below thread...https://www.gatewaytoairguns.org/GTA/index.php?topic=151471.0