A.R.M.S.,INC - AR-15 Flip-Up Adjustable Low Profile Rear Sight Black

sight is not bad.. does not come up vert. pics will show this!!!! works well..

I have used this BUIS on several custom carbines and find it to be an excellent choice as a non-primary sight. It is low profile, easy to deploy and sturdy. The apetures, unlike the Magpul MBUS, are steel (not polymer). For me the locking down of the sight and deployment are much more robust than the MBUS as well. I can see no reason why this sight isn't every bit as good as the original ARMS #40-L (a tried and true BUIS) at 1/3 the price.

This is a good product as a back-up sight - it seems durable, is light, very low-profile and deploys easily, when needed. I gave it only 3 stars as the small aperture pops forward a bit (sometimes 30-45 degrees) from the force of "popping up" and then needs to be moved fully out of the way of the 0-200m aperture or moved back to strait to see clearly thru the peep. Also, if you leave it "in between" and try to re-fold the sight into the down position, the small aperture piece can interfere with the latch. In that it is steel, you can't really permanently remove that portion easily either (if you wanted the 0-200m aperture only).

I like to go against the grain, to do things that are less popular or different than the accepted standard, and for affordably polymer back up irons, Magpul MBUS is the standard. I trust arms, I have used arms gear for about a decade, and my dad used arms gear for about a decade before that, and the sights looked pretty good. The don't lock in the up position at all... they flip up and are held in place by spring pressure. When they are up, can you be sure they are always in the same position? I cant be. Because they can move beyond their current up position (which isn't even straight up) or they can move back, and they will stay there... There is just nothing to keep them in their kinda half cocked position. There are a lot of things that I like about the sight, I am not dissatisfied enough to return it, and so far it seems to hold a zero and shoot alright, but man I just can't trust them, and I am fairly disappointed in the design.

First of all I was unable to establish a 25/300 meter zero. The front sight would not go low enough to get 'dead on' at 25 meters. Several rifles with flat rails were the same. It shot 2" too low. More importantly the latch on the rear sight broke off at the pin when my glove snagged on it while charging the weapon. Came off with no effort at all. I suppose mounting it farther down the rail would help but if your mounting this behind something like an Eotech it needs to be as far back as you can mount it. Should not have to be concerned about being gentle with plastic stuff on a tactical arm! A.R.M.S. needs to re-think the latch and maybe make the front sight a couple hundred thousands lower or the rear a little higher. I gave it 2 stars because the unit does have potential with a little re-design work. But as is I won't be getting any more of these for my customers.