Although I would rather have something aftermarket, made specifically for the 15-22, this is my solution so far.
This is a standard replacement cover from Midway, for less then $6, modified using only a hacksaw and a file, in less then 2 hours. YMMV.
It locks closed when the bolt is open. After a last round fired, I want to be able to protect the innards while changing mags, weapons, etc. When you load a new magazine, and snap the bolt closed, it opens.
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