I recall a posting on this, but cannot locate. Anyone know what these two FF forend weigh?

xyzzy45,

I don't have your answer, but I do wonder if I'm alone in wanting an accessory weight FAQ.  

Try the Maryland AR15 site. They have a lot of parts listed. -Justin

Maryland site has the weights of some forends listed, but it is not clear when the barrel nut is included and when it is not, so there is no way to make a comparison that I can see.

Today I found a reference to FFRAS weights on the last page of one of our FACs with the following information:
1. SIR with barrel nut - 19.5 oz
2. RAS II w/ 3 11" panels 14oz
I recall that FIRSH and other FFRAS are in the 8-9oz range, but that is very vague and I do not know whether that was w/ w/o panels