first off, ALL firearm manufacturers are going to reccomend that you do not shoot reloads. it is there way of telling you that if you screw up, and blow yourself / and or the gun apart, they are not liable. that being said, if the ammo is made carefully, there isnt any reason that reloads can not be shot in anything. the issue, as i understand it with the glocks and lead is the polygonal rifleing. i read somewhere that you can buy a conventionally groved barrel for them if you want to shoot lead. but if that is what you are interested in, check on it first, because not being a glock owner, i am not certain about it. as for shooting reloads in a poly pistol, no reason not to. just so long as they are made withing sammi specs, there shouldnt be a problem (other than a warranty issue if there is a problem with the gun). i have shot thousands of rounds of reloads through 5 different poly pistols with no problems whatsoever. bullets types really do not seem to make a difference either, although some need to be seated deeper than others. jacketed, plated or plain lubed lead bullets all seem to work fine once the load is right for that particular gun. the only thing about lead is sometimes, the lube can build up and start to make the rounds not chamber all the way. i find that sometimes happens if i over lube my cast bullets with lee liquid alox. but that is my fault, not the guns.