WE G39E Barrel Fix

Fixes to eliminate barrel wobble on a WE G39(E/K/C) with a coke can and an AR barrel shim.

Aluminium Coke can sheets are used because it does not change shape over time, unlike plastics or telfon tape. It also does not react with plastic/metal parts.

May require a plastic mallet to get a tight fit, certainly for the outer barrel to barrel breech interface part (first diagram).