Rifle Know Nothing needs some help.

[GigG]

I've got a Bushmaster XM-15E2 and have decided that the quad pic rail hand sorta sucks.  What I would like is a slimmer and longer (at least well past the gas block and maybe about 15") foregrip with M-Loks.

 

All ideas are welcome.

[DesertTortoise]

Your handguard options will increase if you get remove the fixed front sight and install a low profile gas block. It's pretty easy to do yourself or any gunsmith can do it. 

[GigG]

18 minutes ago, DesertTortoise said:

Your handguard options will increase if you get remove the fixed front sight and install a low profile gas block. It's pretty easy to do yourself or any gunsmith can do it. 

 

My Bushmaster came from the factory with no fixed front sight.

 

[DesertTortoise]

Ok, you'd still have to replace that one with a low profile block then you can pretty much use any handguard. 

 

I'm assuming it has a standard barrel nut so any handguard with uses a standard barrel nut can be used.

[GigG]

Thanks, I learned something new. I always figured low-profile gas blocks were just gas blocks with the sights cut off.

[emjbe]

One idea for a very smooth Handguard is the Aero Atlas S-1:

https://www.aeroprecisionusa.com/ar15-atlas-s-one-m-lok-handguard

 

It's very smooth - it will feel very different than the quad pic rail you have.  Much easier to hold on to.  Kind of like doing pull-ups on a narrow bar is easier than a huge fat bar. 

 

You'll definitely want a low profile gas block. Make sure you measure the diameter of the barrel (called journal) and find one that will fit your barrel. This measurement is extremely important.

And, if you are doing the work yourself, it will probably be less frustrating to pay the money for a new gas tube (measure the gas length of your barrel and get the right length tube).  While it is possible to re-use your gas tube, sometimes they can be difficult to remove from the gas block and it's a low cost to avoid the frustration.  After you get some experience you'll be able to pop out that gas tube roll pin.

 

For tools, I think that gas block you have is pinned to the barrel so you'll want a good rifle punch set to remove it.  And, those pins may be tapered so punch them out left-to-right (viewed with the rifle shouldered). If it is pinned, there will be 2 slots in the bottom of your barrel for the pins - your new low profile gas block will not use those slots, it will likely have set screws instead.

 

Whichever hand guard you buy, you'll probably be able to pick up the gas block and gas tube from the same manufacturer. Also, the new hand guard will come with a new barrel nut.  You'll have to remove your current barrel nut and use the one that comes with the new handguard.  If you have access to a torque wrench, that it ideal. It's also VERY convenient to have an upper receiver vice or a similar tool that will hold the barrel or upper receiver in a vice.  Magpul makes a simple one, and there are several called "reaction rods" that are very nice.  Pay attention to torque specs and use anti-seize or correct grease on the barrel nut threads. I think the book advice is to torque then loosen then torque the barrel nut 3 times to make sure it stays tight.

 

Also - many gunsmiths will replace hand guards for very reasonable prices and watching them once or twice is a very good way to learn.  While watching a smith pay attention to how they align the gas block to the gas port.

 

Note that everything above is based on mistakes I made ... I did the same thing without the proper tools and vices and it takes longer but can be done.  Last time I needed a handguard replaced I went to Accuracy Speaks and Sean did it while I waited in about 10 minutes.  

[dwbethue]

+1 for the Aero Atlas S-One as long as you don't want to run something directly on top (like an IR Laser/Illuninator or tape switch). I love the way the S-One feels while shooting, but have to "Ranger band" my tape switch at a weird angle when I run a weapon light on it which is not ideal but works.

 

I've been very impressed with my Geissele MK14 rail as well. Very thin and very light considering it has a full length picatinny top rail, but not cheap. I got one on a blem sale and it was still about 50% more than I'd like to have spent lol. Outside of price though, I've got nothing but good things to say about it and will probably be my choice for uppers going forward.

 

Midwest Industries makes some awesome slim line rails as well, both with and without full length top picatinny. 

[Kevrend]

If you are happy with the way your gun already functions, but hate the quadrail, this may be a good option:

 

https://midwestindustriesinc.com/two-piece-ar15-free-float-m-lok-handguard/

 

or something similar. 2 piece rails that will work around your existing gas block without needing to remove it, and don't have the pic rail all over the place.