Posted: 9/6/2023 3:41:10 PM EST
[Last Edit: Mad-Machinist]
IIRC, there were two versions of OA K45 uppers. The older version used IMI Uzi .45 ACP mags with a welded on adapter, and the new version that used the OA polymer mags. The feed ramp on the older version had to be modified in order to use the polymer mags, and OA would do the modification free of charge.
MHO, YMMV, etc.
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