[drx]

Gus:

I've read of a bunch of different ways to properly fit a handguard, and I was wondering which one you advocate. They all seem to involve trimming the bottom and rear to prevent contact with the stock and receiver, but differ in how to keep the handguard from moving around. Some say to bend the ears on the front band, some say to use a piece of rubber under the handguard to hold it up, and some say to use silicone under the clip and/or between the handguard and oprod guide and/or at the front band.

How do you do it? Thanks for any insight.

-Bill

 

[Gus Fisher]

Well, there is no one single way I do it because I try to tailor what I do to the type of rifle and how it will be used. So let's break it down by type of rifle.

Standard Rifle aka Infantry Type rifle, including a Walter Mitty Rifle:

On real G.I. M14's, we just slapped on the handguard and replaced it when it cracked or chipped too much. We did not generally have good epoxy compounds to fix cracks back then. However, since I've learned from NM rifles how fitting a handguard is helpful to accuracy, there are a couple of things I do on handguards for these rifles.

The first is to ensure when the handguard is pushed all the way forward, there is just a tiny bit of space between the front of the receiver and the rear of the handguard. It doesn't take much space at all, as long as you can hold up the handguard on the barrel and see light between the receiver and rear of the handguard, you are just fine. If you can't see light, then file a little off the REAR of the handguard until you can just see light.

The second thing is I prefer to have some light between the bottom of both sides of the handguard and the top of the stock on both sides WHEN you press upwards on the front of the stock while holding the barrel steady. I usually grab the gas cylinder with my right hand while I push up on the stock with my left hand. You must press the stock as far upwards as it will go. If any point or area along either bottom edge of the handguard touches the stock while doing that, I will clear/file that point or area on each side of the handguard. You can run a pencil line on either or both sides of the handguard when you press the stock upwards to use as a guide on where to file it.

In the past, Bill Ricca has kindly posted pictures of the rectangular black rubber like G.I. spacer that was glued to the underside of the rear of the handguard. This was meant to keep a loose handguard from rattling and keep the handguard up off the barrel. I never saw one of those things on Active Duty in the Corps, but I heard of them even in the late 70's. However, those things are rarer than hen's teeth and no one I've ever ran across had one other than Bill. He does NOT have any to sell to my knowledge.

Now, on a standard rifle, you don't need one of those spacers or even using the silicone some folks use. However, if one wants to use either, then go for it. My problem is I personally don't know the best silicone to use and maybe someone else can chime in.

Though we didn't do it on G.I. rifles, I've come to prefer to use gas cylinder shims even on standard rifles. It does NOT hurt reliability in any way and it keeps the gas cylinder from bouncing around and takes a little stress off the barrel threads for the gas cylinder lock.

I usually don't heat and bend up the handguard tabs of the front bands on these rifles as the handguards usually fit tight enough, though a little loose.

NM rifle with standard G.I. "light barrel" or regular barrel contour, IOW not a medium or full heavy barrel:

First you clear the handguard as mentioned above. We put a little more open clearance between the rear of the handguard and the front of the receiver on NM guns. About 3/16" was the average. For these rifles we glued both the front of the handguard to the unitized front band and glued the clip to the handguard.

We heat and bend up the tabs of the front band. I have come to shorten the ends of the tabs just a bit before bending them, to ensure they won't interfere with gas cylinder shims. I use a cutting disc to cut them maybe about 1/8" shorter. Then when I heat and bend the tabs, I keep in mind how close the ends of the tabs are to the top hole in the front band. You want to keep the ends of the tabs back between 1/16" and 3/32" from the hole so they don't tighten against the shims or bugger up the glue job.

Now, after you bend up the tabs, you have to file/fit the front of the handguard so it will go in the front band all the way forward. I DO mean all the way forward where the very front of the handguard is touching the "plate" area of the front band. This will make a stronger joint when you glue the handguard. You have to file and check the bottom of both sides of the handguard lip to get the handguard in so it will go all the way forward. You also usually have to file inside the bottom edges of the handguard to get it to fit in all the way. As to how tight the lip of the handguard should fit into the front band - I don't recommend a tight fit. A tight fit will add a stressor or negative node of vibration to the barrel during firing and may/will cause a little loss of accuracy, though for most people they may never notice it. I fit the lip so it will go into the band without any tight spots. Then you roughen up the lip so glue will stick to it.

You take off the handguard band and roughen the area of the handguard that the clip fits over. This to ensure the glue will stick to it. Then you roughen up around the inside of the top of the front band so glue will stick to it. Then I roughen the inside of the front band where the handguard lip fits into it. I use small rotary stones or carbide cutters in a handy grinder or dremel tool to do this.

The ONLY glue I use to glue the handguards is Hysol Epoxy Patch Kit 1C (White color) or 11C (black color). Even though we used this even when I was first learning how to NM condition a rifle back in 1973, there is no glue I've ever run across in all this time that is better. Loc Tite bought the company that makes this stuff years ago and you get it from them or their distributors. The problem is if you order it from Ellsworth or Wassco, you have to pay an MSDS charge and MSDS handling, so you have to buy enough kits to spread out those charges. I've never been able to find the black !!c kits sold in single quantity kits. You may be able to order a single white 1C kit here without those added charges.

http://www.shoplet.com/Loctite-1C-Hysol-Epoxy-Adhesive-83200/SEPTLS44283200/spdv

OK, this is running long, so will have to go to Part II.

 

[Gus Fisher]

Part II

You have to file the bottom sides of the handguard more for a NM rifle than a standard rifle. Once you get the lip to go into the front band, the next thing you do is file the handguard bottom sides so you have a good 1/16" to 3/32" between the top of the stock and the bottom sides of the handguard when you push upwards on the stock.

OK, I think this is a good place to state the difference between the way the MC NM Armorers glued on the handguard and Army Armorers did it. The Army glued the front of the handguard, but not the band to the handguard. The Army used the silicone under the rear of the handguard to keep it stable in the rear. We always thought that allowed the rear band to move a little during firing and set up varying nodes of vibration. So I always glue the band to the handguard.

BEFORE you glue the handguard on, I've learned to do a couple additional things FIRST. As I am putting the unitized gas cylinder, lock and shims on the barrel to find out the best combination of shims to use, I spray around the barrel immediately behind the shoulder for the gas cylinder with Accra-Release Mold Release. You can use other mold releases, but make sure you use a good mold release. Glue is going to squoosh out under the handguard's front lip and that is actually a good thing. As it hardens, it will act as a foundation the handguard lip rests on and that helps ensure the glue joint won't crack. However, when the barrel wears out, that mold release will allow you to get the gas cylinder and handguard OFF the old barrel a whole lot easier and without having to heat it. it is not a bad idea to spray the GC shims with mold release as well, BUT DO NOT spray mold release on the inside of the front band or the glue won't hold.

Once you have found the correct shims for the unitized gas cylinder and you lock it down with the GC lock, then you can glue on the handguard. DON'T use the glue until you have found the correct shims to use, though.

You have to make a "special tool" out of 1/16" welding rod and brass rod is the best. You can make it out of cheap/thin coat hanger wire - the kind you get on on clothes from the dry cleaners as you want the smaller size wire. You need a piece about 2" long. Flatten out one end by hammering it on the anvil of your vice. Then bend the whole piece into a slightly curved arch. You don't need much bend in it.

I use a small artist's pallet knife to mix and place/force the glue where I want it. I fill the area with glue between the top of the barrel and the entire inside of the front band where the handguard comes fits in. That is enough glue to form the foundation I wrote about earlier. I press/force a little glue on top of the lip of the handguard. This to ensure there are no air spots between the glue and the lip. Then I shove the handguard in so the lip goes all the way up against the plate of the front band.

Next, press/force some glue on the handguard where the band will sit over it. Then press/force some glue on the underside of the handguard band as well. I put a fairly thick layer of glue on the band maybe about 1/16" or a little thicker.

NOW THIS IS IMPORTANT !! There is only one way the band goes on the handguard. The side with the shorter leg that bends upward more goes on the RIGHT side of the barrel. It is bent that way so the op rod will clear it. If you glue it on backwards, it will cause the op rod to rub against it and screw up accuracy and possibly functioning. After I get the glue on the band, I STOP and make sure I have the short end side and place that into the barrel slot on the right side of the barrel. Then you hold the handguard and press the band on over and down onto the handguard so the long end goes into the slot on the left side of the barrel.

Glue should squoosh out on both the front and back of the barrel band when it snaps into place. Take Q tips dipped in acetone and squeeze them so the heads won't hold so much acetone that it will dribble. Use them to clean up the excess glue that squooshed out from the band and up front. Then turn the barreled receiver upside down. You don't want glue between the rear band and the barrel. You can clean most of it out with toothpicks as well as the acetone dipped Q tips. Look up front at the underside of the front of the handguard. Glue between the barrel and handguard THERE is GOOD for making that foundation, but you don't want glue hardening so it will be below the surface of the lips of the front band. I use Q Tips there as well to push in and clean up the glue close to the barrel as you can get with Q Tips.

Now, turn the barreled receiver right side up. Take that curved 2" piece of rod and slide the flattened end in front of the receiver and down under the rear of the handguard. That's why we need the slight curvature. Push or tap it in just enough that the rear of the handguard is lifted off the barrel. You don't want to push it in so far that it will force the band to spring upwards. If that causes a little more glue to squoosh out and it usually does, clean it up with acetone dipped Q Tips. Then examine everywhere the glue shows to ensure you have it cleaned up correctly. I've been doing it for almost 40 years now and I still check it thoroughly and sometimes have to clean up something a bit more. Set the barreled receiver right side up and let the glue cure overnight.

OK, we have to go on to Part III.

 

[Gus Fisher]

Part III

For medium heavy or full heavy barrels, we do all the previous steps the same way BUT we have to clear the underside ribs of the handguard a bit for the larger breech and barrel diameters.

On a medium heavy barrel, you only have the rear half of the handguards ribs to clear, but on a full heavy barrel, you have to do most all of the ribs AND the ribs that run parallel to the length of the handguard on both sides.

I clear them by using a cartridge sanding roll, though it can be done using a half round file. You want to file/cut a flat edge on the ribs that would contact the barrel and the oversize op rod guide on a full heavy barrel. I put regular grease on the barrel and lay the handguard over the barrel and push it down. The grease transferred to the underside of the handguard will show you where high spots are and you sand them down a bit further. Now don't go hog wild or you will cut through the handguard ribs and leave a hole there. Go slowly and only take a little off at a time until the handguard easily fits down on the barrel. Stop there because you will use that 2" curved piece of welding rod or coat hanger to keep the handguard off the barrel when you glue it. Oh, it does take a good bit of time to clear the underside ribs for a medium heavy barrel and even for more for a full heavy barrel, so expect that and go SLOWLY as you clear them.

I am now about "typed out." Grin. I'll go back over this later on tonight or tomorrow to ensure I haven't left anything out or if I have made a mistake. So please allow me a day or so to do that before you try this procedure.

If you have questions, please post them and I'll get to them.

 

[panther308]

All I did on my Springer STD was grind down the sides to get clearance as far as bending the front ears it was already done from the factory and I opted not to glue it into the front as my GC is not unitized only shimmed

 

[drx]

Gus:

As always you go above and beyond. Thank you for the very thorough explanation of the procedures. You should write a book! I'd buy it, heck, I'd buy 10. GI2

 

[Gus Fisher]

DRX, Thank you for the kind words.

Panther308, thanks for posting the pictures. The last picture especially illustrates something I did not completely mention.

Folks, notice how in Panther's last picture that the bottom of the front handguard is slightly ABOVE the lower edge of the front band lips? This is something you have to do rather frequently to ensure the bottom of the handguard does not touch the top of the stock and ESPECIALLY with commericial stocks where the stock ferrule may sit lower than called for by the G.I. drawing specs.

On some NM rifles, I've had to take even more off the front of the handguard and go a little higher than the bottom of the front of the handguard is on Panther's picture.

So don't be concerned if you have to do that.

 

[Orlando]

I have used High Temp Silicone RTV Gasket Silicone for both Garand and M14 handguards.
It holds up well to heat and oil
I used it on this Garand handguard to "hold it up" off the barrel as the wood was chiped out under the clip

 

[Phil "Murphy" McGrath]

In Panther308's pic's you can see the wavyness of the trim, too prevent this I use some masking tape too keep the edge straight along its lenth and as a guide line, a palm sander works wonders for removing the extra overhang on M14 handguards its a 5min trim job just don't breath the dust. This keeps the edges clean, it also works on wood M1 rifle handguards, just takes a little more time.

 

[Nut behind the stock]

Phil, I use a 10"x4" block of wood with some sandpaper wrapped around and stapled to it. That way the bottom stays even.

I did my Garand upper guard like that after reading Mr. Fishers posts a few years ago. On that DGR walnut stockset I had firm contact between the handguard and the stock's forend really raising cain with my groups as the gun got warm.

Thanks again Mr. Fisher for being kind and sharing your brain power.DI5

 

[Dogbone13]

After drawing a line with a pencil to mark the amount of plastic to remove from the right side of the handguard, I used a very small Phillips screwdriver to pop off the bands and a small wood block with sandpaper stapled to it to remove the marked amount. Snapped the handguard back in place and reassembled the rifle. Now I can slide a paper business card between the handguard and the stock on both sides. 20 minute job. Waiting to see if this will improve accuracy. Thanks for the prior posts to help me get this done.