I'm looking to get a BUIS shortly and would like some opinions on which one is the best. I don't presently have any optics but will probably go with an Eotech. If I have my facts straight the #40A and the #40L are the better A.R.M.S. sights and the LMT is a good one ,too right? Thanks in advance for the help.

The 40L is top of the pile for best all round, especialy if you later get a magnified optic that requires that you go over a fold down sight to get the proper eye relief and lower ht.
Jack

Anything from ARMS, KAC, LMT or Troy is going to serve you well, depending on the purpose, the type of optic its going to interact with and the feature that are important to you.

There is no "best."

thanks guys for the info

The LMT does have the widest sight channel, therefore the widest FOV.  I use it with an EOTech and love it.  However, it is fixed.  So if you think you will ever get any optic that needs to sit back toward you, get a folding BUIS.  

I'm in the same boat as knightone. I'm happy with this set-up. But you're tracking on the models; I'm sure any of those will do you just fine, it's just a matter of whether you want a flip-up model or not.

Any of the name brands will work as a back up, while the LMT fixed works great as a primary.  Just decide if you want folding or fixed, and what type of optic you will be using before you decide ont he BUIS.

Quoted: The 40L is top of the pile for best all round, especialy if you later get a magnified optic that requires that you go over a fold down sight to get the proper eye relief and lower ht. Jack

As someone in that position(magnified glass and 40A) I can tell you that is for damn sure. I got a leupold 1-4 sitting over an ARMS#40A and my scope ain't in the right position really. It needs to move back but it can't cuz the #40A is a bit to tall. One of these days I'll get off my lazy butt and order a 40L. Maybe when I redo the pre-ban.

I just installed a 40L and it seems to be a quality piece of equipment. It will be used
with a "soon to arrive" TA31A. Hopefully I can get some rounds down range this month
and test the package.

I agree with Lumpy196.

Any opinions on the GG&G BUIS?   I am getting ready to put a scope on my flat top AR.  I wanted to use an ARMS 38ex, but I'm worried the scope won't clear the sight on the #38.  The GG&G sight looks like it doesn't stick up as high when its folded down

When using the #38 sleeves, the platform is built up in front of the folding sight, and you will go over it with more clearance than anything out there that is only going off the receiver. Your clear to go
Jack

Quoted: Any opinions on the GG&G BUIS?   I am getting ready to put a scope on my flat top AR.  I wanted to use an ARMS 38ex, but I'm worried the scope won't clear the sight on the #38.  The GG&G sight looks like it doesn't stick up as high when its folded down

I have been using their A2 BUIS.  It's nice, works good for me!

I have one for sale if you are interested.

Hell must have frozen over because I actually agree with Jack!

The 40L is fantastic.

I say this because I prefer the small aperture over the large, even at close ranges.

If you prefer the large aperture then the TROY Ind. might be the best for you as that is the only aperture it has.

The ARMS # 40L is the best 0-300 meter backup out.  it returns to upright when nocked down, has a low profile, non-corrosive hardware, and now it has a full 300meter aperature (the annoying half aperature of the #40 was the only reason I didn't stick with it.< it also had to be folded to the 0-200 to fold, not an issue with the #40L

Forgot one thing... if wings bother you, I reccomend the KAC 0-300 as it is about as non-obtrusive as it gets for a sight (just a narrow post with a peep attached, no wings, windage knob or anything to get in the way.)



The KAC 0-600meter sight is the best 0-600meter BDC sight.  (The other 600M BUIS is ridiculed by most.)

"When using the #38 sleeves, the platform is built up in front of the folding sight, and you will go over it with more clearance than anything out there that is only going off the receiver. Your clear to go

especialy if you later get a magnified optic that requires that you go over a fold down sight to get the proper eye relief and lower ht."


No offense but both of these comments make little to no sense at all.  

Most backup sights allready fold (exception being LMT chopped A2's and clones)  

The SWAN sleeves have a built in rear sight at the same height as without a sleeve, they only create a problem, your optics mount higher and your sight is the same height, = you can't co-whitness with EO-techs #2 reason I sold my #40 (had a SIR #45)

If you are saying mount the rear sight on the SWAN sleeve it is equally stupid:
A: Your front sight will be too short
B: without the SWAN sleeve you would have the same cleareance as you currently have (you have raised the optic mounting platform by the same height as the sight platform)  
C: The built up platform screws with clearance (it's just more crap in your field of view), it makes more clearance only if you have a PAQ-4 and have to mount it on top, in which case it gives you the lowest PAQ4 top mounting, providing more clearance than the PAQ4 with it's supplied RAS mount.

SOLUTION: Don't get the #38 and YOU WILL BE BETTER OFF.  (you won't need a taller front sight, and you won't have to mount the sight on the SWAN sleeve to get the SAME co-whitness as if you had not gotten the sleeve at all.)

If you are related to ARMS why don't you answer my questions about my Throwlevers on my #19, afterall if it is your product, you should know the answers.

Quoted: Anything from ARMS, KAC, LMT or Troy is going to serve you well, depending on the purpose, the type of optic its going to interact with and the feature that are important to you. There is no "best."

What he said.

However,
I'm partial to the ARMS #40 A, myself. I  feel the #40 is the best designed BUIS from an engineering standpoint.
Every feature that is needed or desired is covered by the #40.

Also the price won't break the bank and is lower than what it should or could be.

"I'm partial to the ARMS #40 A, myself. I feel the #40 is the best designed BUIS from an engineering standpoint.
Every feature that is needed or desired is covered by the #40."



Everything but a sight that will spring up with a 300meter aperature ready to use, and a full 300meter aperature.

Those two IMPORTANT FEATURES and a lower profile are added with the #40L.

DITTO!
Jack

Is it lower than the KAC 300 Meter BUIS?

Who else has an non-folding A2 rear sight?  Larue Tactical has one on their web-site, and if it gets reviews like every thing else they have put out... look out world!  It's the first one I have seen with a throw lever instead of a carry-handle-style tightening knob.  Comparable price to LMT's unit definitely makes this one to watch.

http://www.laruetactical.com

-Randy

Quoted: Is it lower than the KAC 300 Meter BUIS?

No, but only by a smidgen.  The 300m is about .312" in the center, where counts, and the adjustment knob brings the side up to about .225" or so for a side height of about .537" give or take.

The #40-L is .600" in height.