I do not trust the standard Glock front sight. It is made of plastic and pins to the slide underneath. To me, replacing the standard plastic Glock sights is a NECESSITY and you can buy the Glock with steel or tritium sights or have them installed aftermarket. It's the weakest point in the Glock design.
No
Aligning front/rear sights
No
Aiming.
Aligning front/rear sights
Aiming.
Rifles, bayonets, machine guns, knives and pistols.
No, the Glock 22 barrel has an outside diameter that is larger than the hole in the front of the Glock 17 slide. your safest option is to buy a Glock 22 and a 9mm conversion barrel for the 22 slide. Then with the correct magazines you could use either 9mm or .40 S&W in a single frame and slide.
Sight alignment is the process of properly lining up the eye with the rear and front sights on open or aperture sights.:)
There are revolvers which have no safety mechanism, although more modern designs tend to have a transfer bar mechanism, which prevents the hammer from making contact with the round unless the trigger is actually pulled. This allows for a revolver to be safely carried with all cylinders loaded, whereas earlier designs which lacked this feature would have a decocked hammer making contact with the round in the chamber lined up with the barrel. Many pistols won't have a traditional safety mechanism of the sort which will actually prevent the trigger from being pulled. Some pistols, such as the Sig-Sauer pistols, some models of CZ pistols, etc. have a decocking mechanism, which allows the hammer to be lowered without the risk of it slipping and striking the round in the chamber. Others, such as the Glock, have a trigger block which must be depressed before the trigger can be pulled. On the Glock, this is part of the trigger itself, whereas the Heckler & Koch P7 has it on the front part of the grip.
Most aftermarket sights are fiberoptic types such as Williams FireSights or the Tru-Glo sights. I dont know of any specific target applications.
Best left to a gunsmith