Uh oh, EOTech 552 wont fit on M4 with LMT BUIS

AR Sponsor:

[ARCHIVED THREAD] - Uh oh, EOTech 552 wont fit on M4 with LMT BUIS

Posted: 4/5/2006 1:20:10 PM EDT

I have an LMT M4 upper (w/ fat M4 handguards) with the LMT BUIS, and my new Eotech 552 (with Accucam) wont fit on the rail while the BUIS is mounted, since the front hits the handguards and the rear touches the the BUIS, preventing it from locking down by just a hair.

To mount it, I would have to move the BUIS back one slot, which puts its rear edge beyond the end of the charging handle (I normally have its rear flush with the rear of the reciever).

What's the lowest/cheapest riser solution out there for this problem?

Kharn

Posted: 4/5/2006 1:36:56 PM EDT

[#1]

I use an LMT BUIS also but I preferr to not use a riser and find I get a perfect co-witness without it . Have you tried it without the accucam?

Posted: 4/5/2006 1:39:14 PM EDT

[#2]

The Accucam doesnt change the mounting height or length, it just replaces the threaded screw with a cam-actuated one.

Kharn

Posted: 4/5/2006 1:42:19 PM EDT

[#3]

Sell it and get an aimpoint

I am thinking of the RRA Dominator mount when i pick up an eo-thing'E

ADCO link

Posted: 4/5/2006 1:53:42 PM EDT

[#4]

Quoted:
Sell it and get an aimpoint

If I'd wanted an Aimpoint, I would've bought one.

Kharn

Posted: 4/5/2006 1:55:56 PM EDT

[#5]

Quoted:
What's the lowest/cheapest riser solution out there for this problem?

Maybe the YHM Eotech riser

Posted: 4/5/2006 2:08:48 PM EDT

[#6]

Quoted:
Quoted:
What's the lowest/cheapest riser solution out there for this problem?

Maybe the YHM Eotech riser

Does that extend the entire length of the upper reciever? I'd hate to have to cut off the rear, mill extra slots (to get the distance from the front right so the BUIS can fit), and then reanodize it.

Kharn

Posted: 4/5/2006 2:12:38 PM EDT

[#7]

I had a similar problem with my LMTupper and Matech rear sight, i was able to file down the top rear of the handguard about an 1/8 inch on an angle , this allowed the Eotech to sit down on the flat top.

Posted: 4/5/2006 2:21:56 PM EDT

[#8]

Quoted:
What's the lowest/cheapest riser solution out there for this problem?

YHM - I think I mentioned it in the EOTech/Riser thread in the Optics Forum (http://www.ar15.com/forums/topic.html?b=3&f=18&t=276546).

Though for the cost of the YHM + the Accucam you could have had the superior LaRue Mount

.

Posted: 4/5/2006 3:27:26 PM EDT

[#9]

Quoted:
I had a similar problem with my LMTupper and Matech rear sight, i was able to file down the top rear of the handguard about an 1/8 inch on an angle , this allowed the Eotech to sit down on the flat top.

Well, it certainly was more than 1/8" required to solve my problem, I had to have the EOTech forward enough for me to see the "T4" mark, so it took a lot of dremeling to get it to fit (and the fit still isnt perfect, it required 5 full turns of the windage knob to get the EOTech cowitnessed with the irons, so I'll have to go back and do more dremeling later). At least CLP turned the sanded portions of the handguards back to black.

Kharn

Posted: 4/6/2006 4:00:29 AM EDT

[#10]

Bump, I'm going to buy the riser and a new handguard, the material I removed is just too much for my liking. Anyone know the specs on the YHM rail mentioned above?

Kharn

Posted: 4/6/2006 4:08:06 AM EDT

[#11]

Quoted:
Sell it and get an aimpoint

I am thinking of the RRA Dominator mount when i pick up an eo-thing'E

ADCO link

Why go with an inferrior product.
Pat

Posted: 4/6/2006 5:25:48 AM EDT

[#12]

Quoted:
Quoted:
What's the lowest/cheapest riser solution out there for this problem?

YHM - I think I mentioned it in the EOTech/Riser thread in the Optics Forum (http://www.ar15.com/forums/topic.html?b=3&f=18&t=276546).

Though for the cost of the YHM + the Accucam you could have had the superior LaRue Mount .

Yep, that is ashame too... The LaRue mount allows the EO to clear M4 handguards without any dremeling.

I really like my RRA Dominator too though. Not that you will, but if you were so inclined, you could sell the LMT and get a Dominator for about the same additional cost as the flimsy (to me) YHM mount.

The Gen2 Dominator mount was specifically re-designed to fit on rifles with M4 handguards.

Posted: 4/6/2006 5:32:21 AM EDT

[#13]

Quoted:
Quoted:
Quoted:
What's the lowest/cheapest riser solution out there for this problem?

YHM - I think I mentioned it in the EOTech/Riser thread in the Optics Forum (http://www.ar15.com/forums/topic.html?b=3&f=18&t=276546).

Though for the cost of the YHM + the Accucam you could have had the superior LaRue Mount .

Yep, that is ashame too... The LaRue mount allows the EO to clear M4 handguards without any dremeling.

I really like my RRA Dominator too though. Not that you will, but if you were so inclined, you could sell the LMT and get a Dominator for about the same additional cost as the flimsy (to me) YHM mount.

The Gen2 Dominator mount was specifically re-designed to fit on rifles with M4 handguards.

I have a Bushmaster M4 set up with Surefire handguards and am using the LMT bus and the EOTECH with Accucam is it the handguards causing the problem on the LMT upper?

Posted: 4/6/2006 5:44:35 AM EDT

[#14]

Yes, its the LMT M4 handguards which are apparently quite huge. I took pics before I dremeled, I'll take some more tonight and upload'em.

Kharn

Posted: 4/6/2006 5:50:52 AM EDT

[#15]

I have the LMT M4 14.5 w/ 551 eotech I like the 1 inch smaller size alot better!

Change hand guards to regular and you should be fine?

Also I like my 551 just the WAY IT COMES! NO EXTRA MOUNT

I have no trouble with it at all. (front sight dont bother me)

I dont like mount on mount. KISS

But have heard nothing BAD about Larue eotech mount. In fact alot of guys love them?

Posted: 4/6/2006 6:18:42 AM EDT

[#16]

Quoted:
I have the LMT M4 14.5 w/ 551 eotech I like the 1 inch smaller size alot better!

Change hand guards to regular and you should be fine?

Also I like my 551 just the WAY IT COMES! NO EXTRA MOUNT

I have no trouble with it at all. (front sight dont bother me)

I dont like mount on mount. KISS

But have heard nothing BAD about Larue eotech mount. In fact alot of guys love them?

In general Larue is the best mount out there but I sold the one I had do to it not working with the
LMT BUIS. I liked the BUIS better then the mount.

Posted: 4/8/2006 7:34:17 AM EDT

[#17]

Here's the pics I previously mentioned:

You can see how the EOTech protrudes over the handguards a little far. The exposed slot between the 552 and the LMT BUIS is the "T4" slot using LMT's numbering scheme.

One view of how much I had to take off, CLP turned the handguards black again (the sanded area was grey).

You can see the difference in profile between the upper (after sanding) and lower handguards.

Two close-ups of the sanded area.

Its still not 100%, but its good enough for the time being. I'll buy the Dominator after I take another business trip and get its perdiem payout.

Kharn

Posted: 4/8/2006 8:50:15 AM EDT

[#18]

I was under the impression that it was touching the handguard not over lapping it, i hope i didnt steer you down the wrong path

Posted: 4/8/2006 1:02:25 PM EDT

[#19]

Buy a rail to replace the handguards and mount the EOTech on the forward rail just in front of the delta ring where it belongs. Remember, it is a reflex sight and the farther forward you mount it, the better.

Posted: 4/8/2006 1:06:43 PM EDT

[#20]

Its a 14.5" barrel, with a Phantom welded on the end.

Kharn

Posted: 4/8/2006 1:14:22 PM EDT

[#21]

That won't stop you from being able to remove the handguards and put a standard KAC RAS or the like on it. All you need to do is take one off, put the other on and tighten a screw. Then you have more real estate on which you can mount your optic. I also noticed that you have a bipod. The rail would do well for that item also.

Posted: 4/8/2006 1:17:16 PM EDT

[#22]

Oh, that shows how much I keep up on the latest accesories.

The bipod was just for the picture, I normally dont use it on the carbine.

Kharn

Posted: 4/8/2006 1:34:12 PM EDT

[#23]

Just to note that the Troy MRF-C also mounts up without removing the front sight/flash hider. I installed one on my 16" lightweight and it went on without a hitch. Works good, not heavy by 4 rail standards, though not the lightest either.

Futuristic

Posted: 4/8/2006 3:20:25 PM EDT

[#24]

.

Posted: 4/8/2006 3:51:23 PM EDT

[#25]

The best solution as stated above:

Buy some slimmer carbine handguards instead of using the M4 style Handguards.

When I had an Eotech I could hang it all the way forward if I wanted to using carbine handguards. I guess if you insist on having M4 handguards than you would need a riser, but if it was me I'd just spend $5-20 for a set of used or new carbine handguards. To me the principle of easiest, cheapest and least necessary part to change applies here. I see a bunch of post offering complex and costly solutions to an otherwise simple problem.

Of course if you must have the M4 handguards than again, a Larue riser is the only way to go.

Posted: 4/8/2006 7:55:51 PM EDT

[#26]

WE CAN MAKE IT FIT ...

Posted: 4/9/2006 3:33:36 AM EDT

[#27]

Yeah, looks like the LT works fine with the LMT Buis. You could even move it aft a couple slots to snuggle up if you wanted to? Whats the prob with that plan?

Posted: 4/9/2006 4:43:36 AM EDT

[#28]

Quoted:
photos.imageevent.com/smglee/mstn/DSCN1410.jpg

WE CAN MAKE IT FIT ...

Wes,
Can you post a pic with out the Eotech just the LMT BUIS and LT mount. Does that only work with the LT forends? Thanks

Posted: 4/9/2006 6:33:19 AM EDT

[#29]

"FLYNAVY" LIVES - GOOD TO HEAR FROM YOU. HOPE ALL IS WELL AT YOUR END.

NO SUCH PIC AVAILABLE - SORRY. THE UPPER IS GONE.

THIS ONLY WORKS WITH LARUE FORENDS. THE HANDGUARD NUTS ON OTHER BRANDS ARE TOO BIG FOR THE MOUNT TO CLEAR.

NO, IT CAN'T GO AFT. THERE NEEDS TO BE A RAIL ANCHOR POINT FOR THE SPRING LOADED BALL DETENT UP FRONT. THIS IS AS FAR AFT AS IT CAN GO.

WES