Coal Dragger
member
At 300K rounds any firearm will have had a whole slew of parts replaced. If by firearm all you mean is the frame, then yes there are Glocks out there potentially with those kind of round counts. However the barrels have been replaced, recoil springs, extractors, ejectors, small springs, the slide, probably some stuff I forgot.
For example the late Todd Louis Green tested a Gen 4 G17 and retired the pistol at "only" 71,260 rounds due the slide being damaged from erosion of the breech face. He also had parts breakages and plenty of stoppages. Ironically the ignorant masses who hate "tupperware" guns always kvetch about the polymer frame, while it is much more likely that the steel parts that actually still take all the stress are most likely to fail. Glock uses re-sulfurized steel for their slides, because it is easier and cheaper to machine. Salt bath nitriding it then makes it's surface hardness durable enough, but it is a compromise. A harder tougher steel can last longer particularly when it too is salt bath nitrided, but it would drive costs up to gain a level of durability even the most hard core users will seldom need. Heckler and Koch uses harder tougher steels for example and it is reflected in the cost of their pistols, while it does make for more durability of the steel parts fact is either brand will digest enough ammo that if the cost is tallied would have paid for a decent used car before either one fails.
http://pistol-training.com/archives/6885
For example the late Todd Louis Green tested a Gen 4 G17 and retired the pistol at "only" 71,260 rounds due the slide being damaged from erosion of the breech face. He also had parts breakages and plenty of stoppages. Ironically the ignorant masses who hate "tupperware" guns always kvetch about the polymer frame, while it is much more likely that the steel parts that actually still take all the stress are most likely to fail. Glock uses re-sulfurized steel for their slides, because it is easier and cheaper to machine. Salt bath nitriding it then makes it's surface hardness durable enough, but it is a compromise. A harder tougher steel can last longer particularly when it too is salt bath nitrided, but it would drive costs up to gain a level of durability even the most hard core users will seldom need. Heckler and Koch uses harder tougher steels for example and it is reflected in the cost of their pistols, while it does make for more durability of the steel parts fact is either brand will digest enough ammo that if the cost is tallied would have paid for a decent used car before either one fails.
http://pistol-training.com/archives/6885
