YHM FF Handguards - Page 2

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[ARCHIVED THREAD] - YHM FF Handguards (Page 2 of 2)

Posted: 1/6/2006 5:34:34 PM EDT

[#1]

So far, the major problems quoted are:

A: The forend is retained by a locking collar and it can break loose, causing the forend to rotate when used with a bipod or VGF.
B: The locking ring has shallow locking grooves and needs a special wrench to properly tighten it down so that "A" is not an issue.
C: There is no positive indexing feature to locate the top rail straight up such as a DD, LaRue, Knights, PRI etc...

My setscrew solution mentioned earlier in the thread completely solves these issues.
ANYONE can drill a simple hole through the handguard and into the barrel nut, tap it and loctite a setscrew into place.
This is trivial work, even for a poorly equipped garage workshop.
Once the forend is aligned and a setscrew added, all the above problems go away.

One legitimate fault is that some VFG's will not fit on the rails because they do NOT follow all the picatinny dimensions.
This mostly has to do with the amount of space BELOW the rail for the locking mechanism to clear.
I don't remember the brands, but there are a couple VFG's that require ALL of the picatinny specs in order to fit.
This issue of space below the rail is also why DD, Knights & LaRue handguards have a smaller diameter clearance circle inside and require special low profile gas blocks to fit underneath the rails.

One un-spoken issue of he YHM forends that you don't hear about is that they are not expensive enough.
Some guys don't want them because all the other ninjas at the mall will know that you only paid $160 for your full length quad rail handguard, so you must be poor...

In their mind, paying $300+ for a rail system makes it better.
If you are getting the $300+ rail, get it for the right reasons like folowing the picatinny specs, positive indexing so the rails can only be installed straight up and the locking mechanish that will keep it from EVER coming loose.
Don't buy it just because that's what all the other ninjas have.

Posted: 1/6/2006 6:25:06 PM EDT

[#2]

Building my first Ar totally from scratch and going to use YHM customizable forearm system. Have read the ff building for dummy's thread a few times. Please correct me if necessary , but based on my reading of the thread ( no reinstallation of rings), I do not need to order the typical snap ring, weld spring, delta ring, or barrel nut. The YHM comes with a barrel nut and a jam nut. Sorry about seeming so anal, but I'm gonna be really pissed if I get stopped in mid build by lack of a $ 0.10 washer.

Posted: 1/6/2006 6:47:29 PM EDT

[#3]

my YHM handguard is great. no complaints. great piece.

s.tank

Posted: 1/6/2006 6:55:38 PM EDT

[#4]

Quoted:
based on my reading of the thread ( no reinstallation of rings), I do not need to order the typical snap ring, weld spring, delta ring, or barrel nut. The YHM comes with a barrel nut and a jam nut.

That's correct.
You will not need a regular barrel nut, delta ring, snap ring or spring.
The YHM barrel nut replaces ALL of that.

Posted: 1/6/2006 7:03:23 PM EDT

[#5]

Thank you very much Mr. Rausch

Posted: 1/6/2006 7:58:42 PM EDT

[#6]

I have a YHM customizable FFT on a SPRish build I did. It seems robust for it's task. It was easy to put on and I have no complaints so far.

Posted: 1/6/2006 8:21:05 PM EDT

[#7]

Quoted:
So far, the major problems quoted are:

A: The forend is retained by a locking collar and it can break loose, causing the forend to rotate when used with a bipod or VGF.
B: The locking ring has shallow locking grooves and needs a special wrench to properly tighten it down so that "A" is not an issue.
C: There is no positive indexing feature to locate the top rail straight up such as a DD, LaRue, Knights, PRI etc...

My setscrew solution mentioned earlier in the thread completely solves these issues.
ANYONE can drill a simple hole through the handguard and into the barrel nut, tap it and loctite a setscrew into place.
This is trivial work, even for a poorly equipped garage workshop.
Once the forend is aligned and a setscrew added, all the above problems go away.

One legitimate fault is that some VFG's will not fit on the rails because they do NOT follow all the picatinny dimensions.
This mostly has to do with the amount of space BELOW the rail for the locking mechanism to clear.
I don't remember the brands, but there are a couple VFG's that require ALL of the picatinny specs in order to fit.
This issue of space below the rail is also why DD, Knights & LaRue handguards have a smaller diameter clearance circle inside and require special low profile gas blocks to fit underneath the rails.

One un-spoken issue of he YHM forends that you don't hear about is that they are not expensive enough.
Some guys don't want them because all the other ninjas at the mall will know that you only paid $160 for your full length quad rail handguard, so you must be poor...
In their mind, paying $300+ for a rail system makes it better.
If you are getting the $300+ rail, get it for the right reasons like folowing the picatinny specs, positive indexing so the rails can only be installed straight up and the locking mechanish that will keep it from EVER coming loose.
Don't buy it just because that's what all the other ninjas have.

Randall - while I agree with most of what you have said - their is one key difference in the YHM style vs LaRue style.

Even with your locking set-screw... the barrel nut can come loose, especially if using a VFG, and torque against the gas tube, causing a malfunction.

With the LaRue - the anti-roll device locks the barrel nut to the upper receiver, and cannot allow the barrel nut to rotate against the gas tube. The LaRue locking device no only locks the tube to the barrel nut - but the whole assembly to the upper receiver. It IS a superior design.

I agree - 99% of us probably dont need this.... even if our tubes spun completely loose, it aint the end of the world. But there is a difference, and there is a reason the YHM starts at $100 while the LaRue starts at $250.

Both tubes are EXCELLENT values.

Posted: 1/6/2006 11:18:24 PM EDT

[#8]

Would something like this work to prevent barrel nut rotation?

obviously not to scale, but kind of like a LaRue plate, only you'd run small bolts through the
YHM b-nut and into the threaded holes on either side of the plate.
The plate would be thick enough to grab the sides of the upper receiver, so it can't move.

between this and the set screw, we just might get a YHM to not rotate!

just an idea...

Posted: 2/14/2006 10:22:17 AM EDT

[#9]

FWIW

i used RED threadlocker on the handguard to barrel nut threads, and did NOT use any loctite for the locking ring.

I used a brass punch and hammer to tighten the lock ring, instead of the special YHM tool. I'm not fond of buying special tools except in extreme cases (USGI barrel wrench, armorer's block, etc...) since I will only use it a few times (I have thus found myself going back to my AR-15 tools quite often).

I have not tried out my YHM FF tube yet, but in past experiences red threadlocker is almost like a permanent attachment until you apply a significant amount of torque. Even when used in situations where there is a lot of heat, it does not tend to come out unless you apply extreme torque. I use it on my ring gear bolts in my rear differential. They stay PUT until you use a break bar...

I do not know why you'd use loctite on the locking ring... since the goal is to prevent the handguard from rotating. Even if you welded the locking ring in place, you can still remove the handguard because once you overcome the forces exerted onto the HG by the locking ring, its loose. Now if you threadlocked the handguard, and really tightened down the lock ring, it should stay in place until you overcame both the adhesion of the threadlocker and the forces exerted by the ring... just my 2 cents and I could be wrong.

Posted: 2/14/2006 10:40:13 AM EDT

[#10]

Quoted:
I do not know why you'd use loctite on the locking ring... since the goal is to prevent the handguard from rotating. Even if you welded the locking ring in place, you can still remove the handguard because once you overcome the forces exerted onto the HG by the locking ring, its loose. Now if you threadlocked the handguard, and really tightened down the lock ring, it should stay in place until you overcame both the adhesion of the threadlocker and the forces exerted by the ring... just my 2 cents and I could be wrong.

Here is why I dont recommend threadlocking the YHM tube to the barrel nut: You will never remove the tube from the nut again.

The bearing surface between the tube and nut is HUGE, especially with those fine threads. Should you ever want to remove the tube, your strap wrench will just unscrew the unit, and the barrel nut will unscrew from the receiver. If you left the gas tube in place, it would stop the nut from turning, but you risk damage to the gas tube, or upper receiver because it is going to take a TON of heat and torque to break that tube loose. Essentially, as long as it stays on the same gun, it should be ok.... you just have to remove them both as a unit every time.

I just built a 9MM upper with a YHM. I REALLY see the benefit of the LaRue system on these, since they lack a gas tube.

I used Randall's recommendation, I drilled a hole thru the tube, into the barrel nut, and tapped it, and installed a set screw. It will keep the tube from spinning, as long as the barrel nut doesnt come loose. However, it is kinda weak. It would be a better solution if the barrel nut was steel. I wasnt overly impressed with it as a fix that allows for abouse on the forearm like other systems can take.

Posted: 2/14/2006 11:21:20 AM EDT

[#11]

Quoted:
while I agree with most of what you have said - their is one key difference in the YHM style vs LaRue style.

Even with your locking set-screw... the barrel nut can come loose, especially if using a VFG, and torque against the gas tube, causing a malfunction.

With the LaRue - the anti-roll device locks the barrel nut to the upper receiver, and cannot allow the barrel nut to rotate against the gas tube. The LaRue locking device no only locks the tube to the barrel nut - but the whole assembly to the upper receiver. It IS a superior design.

These same problems plague the Daniel Defense, Armalite and Knights forends, but for some strange reason (the 99% you quoted) we ultra rarely hear about them having a problem rotating against the gas tube and causing problems.

The 9mm example is a very legitimate reason for the ARD though.
I am working up a simple ARD that will work with YHM barrel nuts.
Stay tuned for more as I finish it...

Posted: 2/14/2006 11:41:14 AM EDT

[#12]

Quoted:
Would something like this work to prevent barrel nut rotation?

i8.photobucket.com/albums/a12/Xnij/YHM_Plate.jpg

obviously not to scale, but kind of like a LaRue plate, only you'd run small bolts through the
YHM b-nut and into the threaded holes on either side of the plate.
The plate would be thick enough to grab the sides of the upper receiver, so it can't move.

between this and the set screw, we just might get a YHM to not rotate!

just an idea...

I've had an idea similar to this for awhile now, though I think a bit simpler.

Posted: 2/14/2006 12:15:59 PM EDT

[#13]

Quoted:
Quoted:
I do not know why you'd use loctite on the locking ring... since the goal is to prevent the handguard from rotating. Even if you welded the locking ring in place, you can still remove the handguard because once you overcome the forces exerted onto the HG by the locking ring, its loose. Now if you threadlocked the handguard, and really tightened down the lock ring, it should stay in place until you overcame both the adhesion of the threadlocker and the forces exerted by the ring... just my 2 cents and I could be wrong.

Here is why I dont recommend threadlocking the YHM tube to the barrel nut: You will never remove the tube from the nut again.

The bearing surface between the tube and nut is HUGE, especially with those fine threads. Should you ever want to remove the tube, your strap wrench will just unscrew the unit, and the barrel nut will unscrew from the receiver. If you left the gas tube in place, it would stop the nut from turning, but you risk damage to the gas tube, or upper receiver because it is going to take a TON of heat and torque to break that tube loose. Essentially, as long as it stays on the same gun, it should be ok.... you just have to remove them both as a unit every time.

I just built a 9MM upper with a YHM. I REALLY see the benefit of the LaRue system on these, since they lack a gas tube.

I used Randall's recommendation, I drilled a hole thru the tube, into the barrel nut, and tapped it, and installed a set screw. It will keep the tube from spinning, as long as the barrel nut doesnt come loose. However, it is kinda weak. It would be a better solution if the barrel nut was steel. I wasnt overly impressed with it as a fix that allows for abouse on the forearm like other systems can take.

Remove the gas tube first. Then remove the entire assembly. Hold the handguard in a fixture or strap wrench and use the barrel nut tool to separate the barrel nut from the handguard. Don't use heat or torque. There's a chemical that breaks down the threadlocker for easier removal.

Posted: 2/14/2006 12:41:31 PM EDT

[#14]

Just ordered my YHM 9.6" solid FF today! Whoopie!

(Can't you also use that white plumbers tape on the threads to make a tight fit?) Not sure about effects of heat.

Posted: 2/14/2006 1:39:56 PM EDT

[#15]

Quoted:
Remove the gas tube first. Then remove the entire assembly. Hold the handguard in a fixture or strap wrench and use the barrel nut tool to separate the barrel nut from the handguard. Don't use heat or torque. There's a chemical that breaks down the threadlocker for easier removal.

Yeah, I thought of that.... I have seen a couple YHM aluminum barrel nuts give just due to torque, when installing them (never happened to me tho). I just imagine with that many threads, that chemical wont be able to penetrate all the threadlocker, and it will take more than 100ft-lbs of torque to seperate it. Just not something I am interested in. I'd rather set screw it for easy disassembly.

Posted: 2/15/2006 2:11:36 PM EDT

[#16]

I actually pulled mine apart on lunch today to put it up for sale it is a spectre XL kit.

I used a propane torch heated the barrel nut area until I smelled the plastic smell of melted thread
locker. (I used the purple thread locker) then I used the YHM wrench and a strap wrench to remove
it I just twisted the YHM wrench and strap wrench in opposite directions and it came off with no problem.

but the use of the YHM wrench made all the difference.

Posted: 2/16/2006 9:46:13 AM EDT

[#17]

Quoted:
I've considered drilling through the handguard into the barrel nut and threading the hole. If you insert a set screw and loctite it the problem should be completely eliminated. Any thoughts on that??

I got a 3 inch piece of 8 ga. copper wire (the Lowes guy scowled at me, but he cut it off and marked it for sale). I gave it a tight hairpin bend, so that the two ends would go into two consecutive holes in my barrel nut. That gave me something to tighten a set screw down on without permanent mods or marring the barrel nut.

Posted: 2/17/2006 4:26:31 PM EDT

[#18]

I've never had a problem with mine. I think it's pretty decent for the price too.

Posted: 2/17/2006 9:28:07 PM EDT

[#19]

Quoted:
Quoted:
while I agree with most of what you have said - their is one key difference in the YHM style vs LaRue style.

Even with your locking set-screw... the barrel nut can come loose, especially if using a VFG, and torque against the gas tube, causing a malfunction.

With the LaRue - the anti-roll device locks the barrel nut to the upper receiver, and cannot allow the barrel nut to rotate against the gas tube. The LaRue locking device no only locks the tube to the barrel nut - but the whole assembly to the upper receiver. It IS a superior design.

These same problems plague the Daniel Defense, Armalite and Knights forends, but for some strange reason (the 99% you quoted) we ultra rarely hear about them having a problem rotating against the gas tube and causing problems.

The 9mm example is a very legitimate reason for the ARD though.
I am working up a simple ARD that will work with YHM barrel nuts.
Stay tuned for more as I finish it...

VERY Intrested. Subscribed.

Posted: 2/17/2006 9:50:17 PM EDT

[#20]

Quoted:
Here's my understanding of the "problems". It does not attach in a very strong manner. Basically to attach the quad rail you screw down the special barrel nut and then the lock ring and then screw on the handguard and back off on the lock ring to cinch it up tight. Some people report the rails unscrewing especially if they bump the foregrip. I personally haven't had any problems with mine, I don't run a VFG though. Also, it's been reported that some of the early YHM rails were out of spec. MJD

This is a great description of how they attach. I had the ultra light midlength free float with the endcap on my rifle and I loved it. I put a little blue loctite on the lock nut and I never had ANY problems with it and I will be buying more of them from YHM. I don't know if you've been to their website but you can get a look at all the different ones they make.

Posted: 2/18/2006 3:54:01 AM EDT

[#21]

Has anyone experienced the loctite allowing the HG to move around after fast mag dumps?

Posted: 2/18/2006 5:57:27 AM EDT

[#22]

Quoted:
Has anyone experienced the loctite allowing the HG to move around after fast mag dumps?

I have. Mine came loose... well, not exactly loose... but I get it REAL hot all the time.... and one day I happened to notice my whole tube had canted about 8 or 9 degrees.... very noticeable. This was with no foregrip installed! I used blue locktite.

Posted: 2/19/2006 3:41:06 PM EDT

[#23]

Using YHM FF LW tube on this one, usually have Knight's but, wanted floating rails w/out having to kick down the baksheesh...I like 'em

No rotation, but I don't use this rifle for high volume of fire

Posted: 2/19/2006 4:53:55 PM EDT

[#24]

Quoted:
Has anyone experienced the loctite allowing the HG to move around after fast mag dumps?

I put blue loctite on mine, but I didn't prep the surfaces properly. I found after some heat got around, it loosened up and turned. Now I put more work into getting it nice and tight on the upper, hasn't moved again since (last couple of months). We'll see. I think if you properly apply the loctite and get it nice and tight (strap wrench and an extra set of hands) you'd be in pretty good shape.

Gundraw

Posted: 2/19/2006 8:26:00 PM EDT

[#25]

I have a YHM on a Beowulf the mid length Spectre and it has not moved.

I have a YHM on a Dissy and it has not moved

I have a YHM on a full length and it has not moved.

I shoot off a bi-pod with the ARMS attachment and the pod Lock and have twisted to make the rifle straight. The tube has not moved. I have tried 3 different Vertical Hand grip and the tube has not moved.
Get the front cap it really looks great and finishes off the build.....

YHM has great service So does Larue and the others so there is no difference there.

I think a index would be ok but with the right spanner wrench you will have no problem making it tight..Call up YHM and ask if they have the wrench.

Posted: 2/20/2006 4:01:07 AM EDT

[#26]

FALARAK:
What is the gas block on you rifle?
I like it!
Thanks

Posted: 2/20/2006 7:34:46 AM EDT

[#27]

Quoted:
FALARAK:
What is the gas block on you rifle?
I like it!
Thanks

It is a home made cut down standard FSB. How-to writeup is here:

www.ar15.com/forums/topic.html?b=3&f=4&t=226782

Posted: 2/20/2006 7:47:28 AM EDT

[#28]

The YHM FFHG customizable tubes are a great idea, but they need to re-drill and tap the swivel stud holes so that you can use them in conjunction with the rails. Right now, I use both swivel stud holes for a side sling mount and a bipod mount (no rails) which works beautifully since the tube is rotated so the vents are right above the gas tube (ala CAR handguards) for added cooling.

[ARCHIVED THREAD] - YHM FF Handguards (Page 2 of 2)

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