UZI Feed Ramps

The original UZI feed ramp was manufactured by stamping the ramp directly into the bottom of the receiver. This method was cheap and fast to manufacture and typically results in good functionality, but it can create feeding problems with hollow point ammunition. Reliability can be improved by throating and polishing the ramp.

When IMI prepared a semi automatic version of the UZI for the United States, they made several minor design changes aimed at making it harder to convert the guns into select fire weapons. One of the changes was to weld in a new feed ramp that had a restrictor ring attached to it. The smaller size of the restrictor ring (along with the smaller hole in the trunion) prevented the UZI SMG barrels from being used in the semi automatic UZI's. As it turned out, the machined feed ramp also resulted in greater reliability in feeding various ammunition, including hollow points.

Semi autos that were converted to full auto will sometimes have just the top half of the restrictor ring cut off. That permits a registered full auto bolt to be used in the gun but still provides support for a semi auto barrel with the reduced chamber diameter.

Realizing that the semi automatic feed ramp improved feeding reliability, it was adapted for use in a full auto UZI by cutting off the restrictor ring. That delivered better reliability while still permitting the use of the larger diameter SMG barrels. Vector Arms offers this as an option on their guns and will also install one on any make UZI for a very reasonable price.