No
Some are. Which model Barret?
Barrett makes a range of .50 rifles, some of which are self loading (semiautomatic), and some of which are bolt action. The most famous of these rifles is the M92/M107, which is semiautomatic.
Barrett Firearms.
50-150 USD
the 50 cal has 10 and the intervention has 5
5.8 feet
100 if it is in mint shape. 50 if it is beat up.
50-100 USD
Between 50-75 dollars.
.50 cents
No. The .50 AE is 33mm in length. The .50 Browning Machine Gun rounds, as used in the Barrett, are 99mm in length. Very substantial difference.
see the link below
Internet, MidWay USA, Barrett