After reading this I’m interested to do a similar build. I’ve got a good idea of what components I want to use, but I’m not sure what length of TRX rail to use. I planned on using a barrel with a carbine length gas system so while a 7" rail would work, I was concerned that I’m limiting my options with regards to mounting accessories as well as dealing with a shortened sight radius. The 9" would have more rail space, but at a slight weight penalty. I’m currently leaning toward a 9" rail, but I was hoping people here with experience with these rails could give me some advice on which might be a better option.
If you are going to use a low profile gas block use the 9". If you are going to use the standard pinned FSB, use the 7".
Go with the 9" or even 11". You won’t notice the weight but you will notice the ability to grip farther forward.
Once you go longer then 7" two things will happen.1-You’ll never buy a 7" rail again,and 2-you’ll wonder what took you so long to get the longer one!!! :dance3:.
As mentioned above, try the longer ones. I’d agree, and say try the 11", and if you don’t like them, it’s not that hard to trade down to shorter, since most folks get one, and try the one 2" longer and decide that’s where they should have started all along (I’ve done this my myself, and have not settled on 11" for most of my applications). The VTAC are worth a look too, especially if you’re planning to run it bare, and bare-pawed. Heck, if you get the 11" VTAC and decide you want the 9" I’ll trade you.
Yeah if you are going over 7" definatly get 11" … its worth it
Or might as well go with a 13" I went with the trx extreme 13" and it’s my new favorite rail of all time.
Thanks for the advice on this one. Most of my AR’s have rifle length handguards so I was a bit uneasy about a 7" rail. I’m glad you guys confirmed my concerns. I wasn’t aware that the weight difference wasn’t that much between the lengths( should have looked at Rob’s chart better).
With many free-float handguard systems the weight formula is:
9.0 + shaved fsb + flip front sight < 7.0 and FSB
A front sight base weighs ~5 oz. That’s a lot. It can be shaved/cut down to be ~1 oz. and a flipup front will be in the 1.5 oz. range. A Troy VTAC Extreme tube goes from 8.50 oz in the 7.0 length to 9.70 oz in the 9.0 length. So…
1 + 1.5 + 1.2 = 3.7 < 5