Yes
No, only if you switch the entire slide. It can be used the other way around however. You can place a G19 barrel into a G32 pistol, and use 9mm, you would also have to use the G19 magazines.
It depends on your intended use, skill level and pocketbook.
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it has to do with the firing pin i know i just bought mine yesterday and it is a glock19 and will empty a 15rd. clip in three trigger pulls. scares the crap out of me so i am probably going to get a different gun or glock model
Glock
Glock 17
The effective range on this certain Glock is about 125 yards.
A week or so
the glock frame is made of hitech polymer. but only the frame
The Glock handgun is manufactured by Glock Ges.m.b.H., an Austrian company founded by Gaston Glock in 1963. Initially producing plastic and metal components, the company gained prominence in the 1980s with the introduction of its innovative polymer-framed pistols. Glocks are now widely used by law enforcement and military personnel around the world, as well as by civilian gun owners.
Very likely, it's the Glock. Glock in general is the best selling pistol in the commercial and law enforcement market.
Glock never made a model 8. You may be thinking of the Glock 18, their only full-auto handgun, which was developed from the 17 for Austria's "Cobra" counter-terrorism unit.