Is there a stock or other options available to make it lock the bcg back and User has to take action to engage it again ?  

Would that get the specific rifle out of "semi-automatic" definition of NJ law ? 

Plug the gas port, take out the gas tube, now your single fire only.  This has been discussed over on the PAFOA forum because PA does not allow SA rifle while hunting.  A Troy pump AR is probably a better solution.  I do not see how any legislation would allow a rile to be a switch hitter on demand. Once SA always SA.

If your using a piston operated ar you can turn the gas piston setting to single fire mode. I have a Ruger and sig sauer that I learned the hard way on....

Hackettstown Guns and Ammo has a Troy pump/collapsible stock if you are interested, $750.00 brand new.

 

(908) 852-5260

I swear I thought you were asking what it takes to make it full auto lol.

Nooooooooo :-)

Thanks for all the replies. Since the first post, I did come across other articles on making it a "non self loading" firearm.