Tighten up handguard

[Ricrock]

Hello,

I have a Sport II and have encountered a problem you might be able to help me with.

There is a steel round plate under the front of the handguard, directly behind the front sight post. This is where the stock and aftermarket drop in handguards attach to the front of the rifle. The back of the handguard attaches (clamps) to the barrel nut with the Delta Ring. This round plate looks to me like it should be a press fit over the barrel.

I have installed an aftermarket handguard and mounted a laser sight to it. I noticed when holding tight to the handguard, it moves up and down a bit. This prevents the laser from holding zero.

Obviously, an excellent cure for this problem would be to free-float the handguard, but I am not willing to do that.

The handguard attaches to this round plate and is very secure with no movement. After removing the handguard and examining the problem I have determined the round plate is moving up and down on the barrel. I have noticed no movement laterally.

What is your recommendation to take out this space which allows the plate to move? The movement is under .010, but that is amplified many times out to the usable range of about 50 feet for a home defense AR.

I am contemplating a thin bead of J-B Weld where the round plate meets the barrel which I believe would stop the movement, but that is kinda a crude fix. Any better suggestions would be appreciated.

Rick

 

[jagular]

It's is a common issue with that type of setup and I wouldn't do anything. If you want a solid rail then go the free float method. There are also other rails that are more solid and can accommodate the standard A2 setup and use the delta ring (like Troy and DD). These will run around $150.

Also remember that lasers aren't for precision shooting. They should be used to get you "on target." I'm not ragging on you but I can't count on how many times I see people at the range with lasers trying to hit the same hole. They're targets usually look worse than someone who just uses open sights.

 

[ChattanoogaPhil]

Hello,

I have a Sport II and have encountered a problem you might be able to help me with.

There is a steel round plate under the front of the handguard, directly behind the front sight post. This is where the stock and aftermarket drop in handguards attach to the front of the rifle. The back of the handguard attaches (clamps) to the barrel nut with the Delta Ring. This round plate looks to me like it should be a press fit over the barrel.

I have installed an aftermarket handguard and mounted a laser sight to it. I noticed when holding tight to the handguard, it moves up and down a bit. This prevents the laser from holding zero.

Obviously, an excellent cure for this problem would be to free-float the handguard, but I am not willing to do that.

The handguard attaches to this round plate and is very secure with no movement. After removing the handguard and examining the problem I have determined the round plate is moving up and down on the barrel. I have noticed no movement laterally.

What is your recommendation to take out this space which allows the plate to move? The movement is under .010, but that is amplified many times out to the usable range of about 50 feet for a home defense AR.

I am contemplating a thin bead of J-B Weld where the round plate meets the barrel which I believe would stop the movement, but that is kinda a crude fix. Any better suggestions would be appreciated.

Rick

Hey Rick,

It is called the handguard cap. It is stationary. The handguard is moving. This is normal.

My better suggestion would be to leave it alone. The handguard is designed to be removable by hand, not J-B welded in place to the handguard cap or otherwise duct taped.

If you want a firm handguard but not free float, consider a two piece drop-in handguard designed for a carbine length gas system. They sell for around $50 or less and are a quick install requiring no special tools. You'll be ready to go in 5 minutes.

 

[Rastoff]

Obviously, an excellent cure for this problem would be to free-float the handguard, but I am not willing to do that.

Then you're not willing to have a stable laser. The best drop-in handguard in the world will move a little. It might not be easily perceptible, but it will move. That movement makes it an unacceptable place to mount any type of sighting system.

If you're hard over on not using a free float system, and you want an accurate laser, it must be mounted on the receiver. A mount like this will make this easier:

 

[Ricrock]

Hey Phil, not to start an argument, but the handguard is NOT moving, it is the "Handguard cap" that is moving not the handguard, about .010 up and down. The handguard I installed is a two piece and it clamps down on the barrel nut and the "handguard cap". The handguard is an extended length carbine handguard, which puts a bit more pressure on the pivot of the handguard. I am absolutely positive it is firmly mounted to the gun and it is the round ring that is moving. Is there any way to make this ring solid on the barrel? Or should I just accept the movement and have a laser that is good for "critical mass"?

 

[Ricrock]

I'm not sure if you know about a locking liquid called "green loctite", but when I was racing cars, it was used on fasteners that were tight and it would migrate itself into the trreads when the bolt was already fastened. Do you think this might tighten up this loose play?

 

[ChattanoogaPhil]

Hey Phil, not to start an argument, but the handguard is NOT moving, it is the "Handguard cap" that is moving not the handguard, about .010 up and down.

You'll have some rotational movement of the handguard and cap, but the handguard cap shouldn't be slopping up and down on the barrel to a significant degree. I wouldn't consider 1/100 as you describe a significant amount for the design.

There's also a wide variety of mounts designed to attach to the front sight. Some on the side, below, mini rail, ring... Here's just one example.




If you've got a scope, there's options for mounting a rail to the scope tube or rings with rail caps.





All of these options, including Rastoff's above are better than trying to Superglue your rifle.

All that said, I think you'll find that lasers are near useless at distance (other than at night). For use at close range whatever movement you're experiencing with the handguard will have a negligible effect for what lasers were designed for, pointing, not precision shooting at distance. As has been repeatedly posted.... I'd just leave it be or get a different handguard.