Thoughts on Mega/Rainier uppers and lowers

[Rhino0427]

So, I decided I have too much money and I need to get rid of some, so why not build another AR? This is my first "from scratch" and I want to do my due diligence. In looking around and doing some research online, Mega/Rainier seem to be universally respected (obviously everyone has their favorites, but M/R seems to be on everyone's top 5 list. I'm looking to build a rifle length, heavy barrel, long ranger shooter built for accuracy, not speed. I like the ambidextrous, Ultramatch, billet, MOD 3 set up as my base. Thoughts?

[Grant H.]

Sounds like an expensive one... LOL.

I built a .308 using mostly the parts you are asking about. The Rainier Ultramatch barrel is awesome.

[zimagold]

I built out a Rainier Ultramatch Billet Set (Mod 2), I believe the only difference from the Mod 3 is the ambidextrous mag release.

Keep in mind that anytime you go off of the typical forged design you can have issues with the wide variety in parts availible. Example: I have a Noveske MUR upper that I really like, but the billet forward assist block interferes with offset iron sights. Its only a problem if the issues interfere with your planned build.

As for the Rainier Billet Set, I found the following "differences."
1. The rear quick point attachment blocks the normal location for a rear breakdown pin detent spring. The spring instead runs vertically, is held in place by a set screw, and requires removal of the hand guard to access. Install was not a big deal, but I removed about 1/4" of the detent spring so the spring tension was similar to a normal install.
2. The rear quick point also expands the section immediately behind the hand grip interface. Installing a Magpul MIAD grip with the large back strap required removal of material in the grip to fit around this enlarged area.

My copy also has a quick attachment point that appears a little too big. 3 of the 7 different quick point loops I tried would snap in place, but not lock in a specific rotation. They would spin freely, but appeared to still have a solid hold. Unlike stock based quick disconnect points where I would simply replace the stock, in this case its an integral part of the receiver.

The set looks awesome and I would buy it again. Just keep the above in mind. My set is currently a pistol waiting to become a 12.5" SBR.

[Rhino0427]

I appreciate the input! From what you're saying it sounds like the more "high speed" you get, the more it requires some gunsmithing instead of being plug and play...not necessarily an issue, but for a first build, I'm not sure how much customization I want to deal with. On the other hand, if its worth doing (and I'm not in any hurry) its worth doing well...

decisions, decisions....

[TheBelly]

I used the MEGA Megalithic Keymod receiver set for a .308 project. I also used the Mega 20" barrel. I am very impressed with both.

[Rhino0427]

I have to admit toying with the idea of going all out and moving to .308. I've always wanted an AR-10 anyhow. A thought occurred to me. If I get the upper/lower combo, it probably adds some cost, but should do away with a lot of the compatibility issues, at least with the main platform. Regardless of caliber, I think I'll go that route just to minimize the gunsmithing on the critical components.

[DireWolf]

I've used Mega billet sets of both the 5.56 and 308 variety, and Ranier ultramatch barrels, and find that the Mega receivers and Ranier barrels are both top notch...tolerances on every receiver I've seen are very good, and the finish is great (with one exception, which they replaced with no hassle at all, great cust service with both companies), and I have no complaints whatsoever with the Ranier barrels I've used.

I've also never had to do any additonal machining on any of my Mega parts to get them to fit/work (other manufacturer parts, not so much...)


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[Rhino0427]

So, just to do due diligence, has anyone had any serious complaints with M/R parts or found something that is significantly better within the same price point?

[TheBelly]

I have to admit toying with the idea of going all out and moving to .308. I've always wanted an AR-10 anyhow. A thought occurred to me. If I get the upper/lower combo, it probably adds some cost, but should do away with a lot of the compatibility issues, at least with the main platform. Regardless of caliber, I think I'll go that route just to minimize the gunsmithing on the critical components.

Compatibility is why I chose the MEGA barrel as well as their MKM receiver set. I have been VERY pleasantly surprised by the fit and finish. My only gripe is that the barrel doesn't have an indexing dimple on the underside of the gas block location.