<Table> <Tr> <Th_colspan="2"> Glock </Th> </Tr> <Tr> <Td_colspan="2"> An early "third - generation" Glock 17 </Td> </Tr> <Tr> <Th> Type </Th> <Td> Semi-automatic pistol Machine pistol (Glock 18) </Td> </Tr> <Tr> <Th> Place of origin </Th> <Td> Austria </Td> </Tr> <Tr> <Th_colspan="2"> Service history </Th> </Tr> <Tr> <Th> In service </Th> <Td> 1982--present </Td> </Tr> <Tr> <Th> Used by </Th> <Td> See Users </Td> </Tr> <Tr> <Th_colspan="2"> Production history </Th> </Tr> <Tr> <Th> Designer </Th> <Td> Gaston Glock </Td> </Tr> <Tr> <Th> Designed </Th> <Td> 1979--1982 </Td> </Tr> <Tr> <Th> Manufacturer </Th> <Td> Glock Ges. m.b.H. </Td> </Tr> <Tr> <Th> Produced </Th> <Td> 1982--present </Td> </Tr> <Tr> <Th> No. built </Th> <Td> 5,000,000 as of 2007 </Td> </Tr> <Tr> <Th> Variants </Th> <Td> See Variants </Td> </Tr> <Tr> <Th_colspan="2"> Specifications </Th> </Tr> <Tr> <Th> Cartridge </Th> <Td> <Ul> <Li> 9 × 19 mm Parabellum (Glock 17, 17L, 18, 19, 19X, 26, 34, 43) </Li> <Li> 10 mm Auto (Glock 20, 29, 40) </Li> <Li>. 45 ACP (Glock 21, 30, 30sf, 36, 41) </Li> <Li>. 40 S&W (Glock 22, 23, 24, 27, 35) </Li> <Li>. 380 ACP (Glock 25, 28, 42) </Li> <Li>. 357 SIG (Glock 31, 32, 33) </Li> <Li>. 45 GAP (Glock 37, 38, 39) </Li> </Ul> </Td> </Tr> <Tr> <Th> Barrels </Th> <Td> </Td> </Tr> <Tr> <Th> Action </Th> <Td> Short recoil, locked breech, tilting barrel (straight blowback for Glock 25 and 28) </Td> </Tr> <Tr> <Th> Muzzle velocity </Th> <Td> 375 m / s (1,230 ft / s) (Glock 17, 17C, 18, 18C) </Td> </Tr> <Tr> <Th> Effective firing range </Th> <Td> 50 m (55 yd) (Glock 17, 17C, 18, 18C) </Td> </Tr> <Tr> <Th> Feed system </Th> <Td> Box magazine, see Variants for capacities </Td> </Tr> <Tr> <Th> Sights </Th> <Td> Fixed, adjustable and tritium - illuminated handgun night sights </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Glock </Th> </Tr>

What is the caliber of a glock 18