Personally I think the SOLGW M89 drive lock is a better solution, as it avoids the issues with the wedge mechanism mentioned by RennBaer. The Hodge Defense S-Lock is very similar, but more difficult to find.

https://sonsoflibertygw.com/product/...ock-rail-m-lok

https://www.bigtexordnance.com/produ...pine-lock-rail