Here are the first pictures of the build...
Will do a pure arrow shooter first, just to learn what works and what doesn't.
Removed the upper receiver and also the trigger/hammer assembly. Then I
made a base plate from 18mm multiplex. Added a trigger and my usual
lock, used a nail that I can bend into shape.
The lock works like a charm!
I will use two 16mm steel tubes as "barrel" and "rail" parts. The draw
is 100% inline with the rails. I plan to make a cocking slide for fast
action. This crossbow will be quick.
No changes to the original M16A1.