I'm in the process of building a 20" upper and want to get a FF tube with rails. The PRI carbon fiber FF tube looks like my best bet. I did consider the KAC FF RAS but that's a lot of rail space I don't really need and I would imagine the KAC would weight a bit more than the PRI. I'll be putting a light on the 20" as well as a vertical grip and bipod that I'll swap out.

I've done some searching on the boards for info and haven't found a heck of a lot on it. If you use or have used this product, I'd appreciate any info you could share.

TIA.

I think the KAC FF RAS weighs less than the PRI tubes, Wes gave us the specs on these once and I don't remember the numbers but I do recall the only thing lighter is Daniel Defense handguards.

Wow, I am in shock. I really thought the carbon fiber would weigh less.

lol don't go into shock yet, I'm frequently wrong [;)]  Let those in the know tell us, I'm just going off the top of my head [:)]

I built my SPR wannabe myself with the PRI tube.  If you can barrel an upper, you can install it.  It idexes with two pins into the barrel nut so you get the rails aligned.  Just be sure you verify this before you put it all together and go to the range and realize your front sight is tilted a tad (don't ask how I know this).

If you want to run a vertical grip, you will want the full length bottom rail, which was "standard" for exactly one production run, I think.  You can swap out the short one for a longer one if you want.

The weights are pretty close between the KAC and the PRI, and I can't remember which one is lighter...

Here's the same old pic of my rifle:

[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=9365[/img]

KAC FFRAS does weight less than the PRI tube.

I have both and find the PRI a little more comfortable to shoot in the kneeling, sitting and standing.

But overall I like the FF RAS more

bsbg, how did you OD that SPR grip?

Thank you for the reply Kevin. That's interesting.

If you don't mind, I'm curious why do you find the PRI more comfortable but you like the FF RAS more.

TIA.

Matt the KAC Rails are not the most pleasant to grab while shooting in thos positions - but the FFRAS does give me lots more usable room to mount stuff.
 
I can mount a 'K' Grip and a Bipod ont he bottom.
 - Plus maybe it is just aesthtics I think it looks better - I dont know - my PRI does nto seem to fit in with the rest...

I completely understand the comfort issue. Don't you cover all the unused rail slots with panels? I agree about the more usable room for mounting.
 


Well, the first upper I'm getting made will be a 14.5" with a KAC FF RAS so I wouldn't mind if my upper matched. [:)]

Seriously, thanks for info. I sincerely appreciate it.