I saw this picture of an MP15 with a daniel defense rail system and was wondering how easy that would be to do. Would it be easier just buying a complete rifle from DD or have any of you put a DD rail system on your mp15? I know i would have to get a new gas block, is there anything else I would have to do?

If you have the tools, the vise, the vise blocks, and a moderate whit of mechanical inclination and the ability to follow a set sequence of instructions, you can do it yourself. You'll need the tools (armorer's wrench, pin punches, etc), the handguard and any handguard specific mounting hardware, and a low profile gas block.

Easy-peasy.

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-John

Depends on what Daniel Defense rail system you are speaking of... if you are looking at the Omega rails, I believe those are drop in.