To those who believe that personal defense starts with the numbers "4" and "5" (and in that order) the GLOCK model 21 has been the answer to their prayers. Compensated/ported for excellent controllability.To many Americans, there is only one caliber for a personal defense handgun and that's the .45 Auto. GLOCK acknowledged that sentiment with the development of the GLOCK 21.

 

Caliber	.45 Auto
Action	Safe Action System
Length (slide)	7.59 inches
Height	5.47 inches
Width	1.27 inches
Length between sights	7.00 inches
Barrel length	4.60 inches
Barrel rifling	right, hexagonal
Length of twist	15.75 inches
Magazine capacity	10 rounds (US civilian)
Mass (weight)
Empty without magazine	25.93 ounces
Empty magazine	3.1 ounces
Full magazine	~12.0 ounces
Trigger pull (standard)	~5.5 pounds
Trigger travel for discharge	0.5 inches
Number of safeties	3