If the barrel has 5.56 printed on it or you have verified with the manufacturer that ALL of their barrels are good for 5.56 ammunition.
There are various types of ammunition. There are also particular guns that use the recently developed 30 mm ammunition. Among them are aircraft guns and armoured vehicle guns.
The equivalent of 5.65 mm ammunition is .22 caliber ammunition.
Depends on what type of 32 ammunition you are referring to.
556 mm with stock retracted, 730 mm with stock extended.
buffaloarms.com
Yes it does, unless your barrel is stamped .223 .
No. They have matching dimensions, but differ in other areas, such as neck angles. .223 ammunition can be safely fired in a 5.56x45mm chamber; 5.56x45 ammunition is not recommended to be used in a .223 Remington chamber.
.0219 inches OR .556 mm (USG)
.30 caliber.
Probably 25 gauge, which is .556 mm thick. However, 26 gauge is close too, it is .478 mm thick.
6.8mm / .270
7.65 = .32 ACP