We just got in more pictures from CMMG’s display at the SHOT show and they are doing some really innovative things that we haven’t seen anywhere else. They have a modular AR-15 upper receiver that can switch back and forth between a standard configuration and a left-handed ejection configuration. It looks like the receiver is cut into a mirror image on both sides, and the ejection port, brass deflector, and forward assist are mounted onto a plate that secures in the rear with two set screws. The dust cover flips up instead of down, but at an angle that wouldn’t interfere with optics mounts, and anyway nobody complains about Stag Arms left-handed uppers that do the same thing. I’m betting that there is a tab or up front holding the front part of that plate in place, which we can’t see because it is underneath the receiver. A flat plate covers the side of the gun opposite from the ejection port. I don’t think this system is designed to be a quick-swap sort of thing where you can change the configuration on a whim. There are just too many unique parts involved, like left-handed bolts and mirror image ejection port/dust cover/forward assist plates for each side (you cant just flip them over, they have to be made for each side). I’m guessing that CMMG wants to sell a wide variety of factory configured guns in left and right-handed versions, in different calibers, and the way to make them most affordable to us is using the same basic upper receiver on all of them. The modular upper seems like a pretty clean and simple idea, and if you look carefully you’ll see that CMMG has a left-hand eject .22 LR conversion kit installed in one of their demo rifles, with a left-hand plate that would work great for .22 LR and 9mm uppers. How trick is that? We also get a peek here at a new forend system I haven’t seen anywhere before. If you look carefully, you can see this forend has two scallops or tabs that interface with the receiver to keep it perfectly aligned. Two set screws at the bottom of the forend probably interface with a custom barrel nut as in the Trox TRX forends. There is a comfortable looking plastic grip area that screws into the forend wherever you want; on the gun with the .22 kit inside it is all the way back towards the receiver, and on the 5.56 gun it is mounted farther forward. There are also short rail chunks that may be mounted wherever the user wishes. Rail systems like this are the way of the future, with optional quick attach grips, heat shields, and rails that only go where you want them, mounted on a slim, light weight chassis underneath. Having a foot or more of heavy “cheese grater” rail weighing down the barrel of the gun is so 2005, don’t you agree? More cool CMMG stuff from the 2012 SHOT Show coming soon!