Don't use the magpul sights on the OR front gas block. Although the Magpul sights are good sights, and reasonably priced, the magpul are plastic and will loosen over time, with repeated heating and cooling of the gas block from firing and you will find yourself having to re-zero frequently. Yes, i know people say thats not so, if you take a shot, wait, and fire again then maybe not as the heat build up is less because of a cycle like this, but i've tried them and get my stuff really hot sometimes and they have always loosened over time leading to a re-zero. I actually melted a magpul front sight base a little once, Magpul even tells you not to use the sight on the gas block for this very reason.
Like said above, the Troy sights are the "benchmark". However, there are some that are just as good and of the same calibur quality. You want the "same plane" sights. Take a look at the Yankee Hill sights >
http://www.yankeehillmachine.com/store/sights.html, for example:
YHM-9627 - Same Plane Flip Front Sight - $85.50
YHM-9680 - Flip Rear Sight - $94.75 (I know it doesn't say 'same plane' but it really is)
There are others on that page also, the Q.D.S. Same Plane Sight System at Yankee Hilll is also a good setup, and a few dollars cheaper then the Troy set.
Do not get a "Gas Block Mounted" sight, as these are intended for gas blocks, most times, that set lower than the OR gas block. You want a same plane system for the OR model.
Other optics, the Primary Arms red dots is good for budget and those guys actually test everything and know it works, and will give good service for range or hunting for the intended use of the item. If your going with a more critical use then just range and paper then your going to spend some $$$ so go EoTech or AimPoint for red dots, I prefer the EoTech myself and the EoTech 512 is starting to show up in some places in deals and sales for right at $300.00, sometimes lower. The EoTech is not a normal red dot, its a holographic sight (dot seems to appear on the target and not in the scope) so its a little different but the same general idea. For red dot, you want a 1 MOA dot really for accuracy, its kinda hard to get an inch group with a dot thats 3 MOA in diameter at 100 yards (people do this, they get a red dot with a 3 MOA dot and wonder why they can't shoot inch groups with it at 100 yards then complain and blame the scope, duh...), and in practical real life critical use you want a 1 MOA dot maximum.
For the mixture of budget and quality, in terms of the red dot and BUIS, I'd go Primary Arms and Yankee Hill. By the way, you can find the yankee hill sights, and some others, along with the Red Dots at the Primary Arms web site (
www.primaryarms.com). Thats about the only place I buy from any more for a lot of things, and they know about the products they carry too rather then just someone on the phone who just takes orders and wants to sell you something so you can call them and discuss your use with them and get the facts good or bad, and if you have a problem with it they will take it back and make it right for you.
