Yes, you can use .38 ammo in a .38 Special firearm as they are compatible with each other.
38 caliber revolver ammo
Federal premium ammo
The glock 21 fires the .45 automatic colt pistol (.45acp, or .45 auto) round.
No
No - they are very different cartridges.
.40 S&W with JACKETED bullets. The polygonal rifling in a Glock does not mix well with lead bullets.
TMJ (Total Metal Jacket) bullets should be safe in a Glock with polygonal rifling. It IS fully jacketed ammo. Glocks do not do well with cast lead bullets.
No, you should not shoot .38 Special ammo out of a Glock 31 chambered in .357 Sig. While the .38 Special and .357 Sig cartridges share the same bullet diameter, the .357 Sig operates at a much higher pressure than the .38 Special. Firing a lower-pressure cartridge in a gun designed for higher-pressure ammunition can lead to dangerous malfunctions and potentially catastrophic failures. It is crucial to always use the correct ammunition specified by the manufacturer for your firearm to ensure safe and proper operation.
9x19mm, also known as 9mm Parabellum or 9mm Luger.
http://www.glockfaq.com/gunsmithing.htm#slideframe The 23 receiver is not compatible with the 38 slide.
NO