Both the .30 Short and the.30 Long rimfire cartridges went out of production about 1917-1920. They are considered an obsolete cartridge, and have not been seen by most folks that are not cartridge collectors. Single specimens are traded and sold by collectors, but are not likely to be shootable due to age. They are also $2-5 per cartridge, and would be rather pricy to shoot. Sorry-
A 22 caliber pistol holds a dose of 22 caliber ammo.
22 caliber ammo
First, it is important to know that the weapon is capable of being fired safely. When you say antique, it just makes my eyebrows raise a little. As far as being able to obtain ammunition for the pistol, there are plenty of online stores that specialize in ammunition for hard-to-find pistols and rilfes. You, of course, will probably pay a premium for it, but that is the way it is for niche items in most industries. Just Google .38 Rimfire ammunition, and you will find a plethera (well, more than one) of companies that will gladly sell you some .38 rimfire ammo. Just please be sure that you KNOW what caliber the gun actually is, and that the pressures used in loading the ammunition you buy are not going to exceed the capabilities of the gun to safely discharge those rounds. Antique guns, in my opinion, should be kept in a case or sold to the highest bidder. Tip: If it's hard to find ammo for, don't shoot it! Glocks are much safer.
No
Can I shoot 380acp caliber out of my 32 pistol?
Not to my knowledge. I do have a .32 rimfire pistol with a little over 100 rounds of ammo for it. It does shoot but I don't shoot it anymore for the simple reason that you can't get any more ammo for it.
Caliber is .45 GAP (Glock auto pistol)
For what? Accuracy, target shooting or beasts of the forest?
Yes- but not very common. There is an automatic pistol caliber known as the .38 Super, which does not interchange with the .38 Special revolver cartridge. There have been a small number of target pistols built to shoot .38 Special Wadcutter target ammo. And there is at least one auto pistol made in caliber .357 Magnum (revolver cartridge). However, revolver ammo is rimmed, and auto pistol ammo is rimless- there are usually feeding problems when an auto pistol is made for revolver ammo.
to my knowledge ammo unless mil spec only is iterchangable with any weapon that fires the same caliber
Yes, the .44 caliber cartridges are pistol/revolver cartridges. Lever action carbines/rifles of the 1800's utilized many pistol calibers so that frontiersmen could use the same ammo for both guns.
Whether for pistol or rifle, .22 Winchester Magnum Rimfire ammo is loaded with bullets ranging from 30 to 50 grains. The standard seems to be 45 grains.