I want to change my setup to a fixed stock, but I'm not sure what parts I need. I saw Rock River Arms has a fixed stock model with a 16 inch barrel that I really like. I'm not sure what buffer and spring to use though.  Thanks in advance.

You need the stock body, a rifle receiver extension (there's only one size––no need to worry about milspec or commercial), a rifle length buffer, a rifle length buffer spring, the stock screw, and the spacer (if you're going with an A2).

Thats assuming that the stock body comes complete with a trap-door buttplate, lower sling loop and sling loop screw.

ETA: depending on the carbine stock you may be using now, the sling loop and screw may transfer, maybe not.  ::shrugg::





Just tryin' to help.






 

Do you want a short fixed stock or a long fixed stock.

Short fixed stock (uses carbine length tube...or retractable length tube)
Sully Stock
ACE Entry
I think RRA makes a short A2 style

Long Stock (typically uses rifle length buffer tube)
Standard A1
Standard A2
Vltor Rifle Modstock (these come in A1/A2 sizes..just picked up a used A1 from a member here...it's pretty nice)
Magpul PRS

I'm sure there are others.  I picked these off the top of my head.