Slim, solid rail - Tacfire AR15/M4 Slim Style Clamp-On Free Float Quad Rail

I was looking for a quad rail for a MK18 pistol build I was doing. While I fully understand the MK18 has a very specific parts list, I also knew there was no way I could afford spending over $1k on an upper. So an inexpensive build was the goal. There are lots of options for KeyMod and MLok slim handguards, but not for a full quad rail. Wanting to keep weight and the overall size down, I wasn't happy with a lot of the other options out there, they were all at least 2.5 inches wide. I found this rail after some searching and was initially leery: I had never heard of Tacfire before and at the price it was clear it was made in China. However, I decided to take a chance and I'm glad I did.

The rail is solid and slim. It measures 2.25 inches wide and is easy to grip. The rail itself has three main pieces: the main rail, the proprietary barrel nut and a locking portion for the rail (basically a cutout portion that screws on). The proprietary barrel nut doesn't require any special tools, just an 12 inch adjustable wrench. You can't get proper torque with an adjustable wrench but I managed to work around that. Don't over-torque the nut, though. It is aluminum and will likely bend. A bonus is that there is no indexing for the gas tube, the barrel nut is low profile as well. Once properly installed, you simply slide the rail over the barrel nut, place the locking piece under the barrel nut, line up the screws and torque them down. There are two additional cross-block screws that prevent forward movement of the rail and, properly torqued and Locktited, any rotation either.

The only complaint I have is that the rail sits so close to the receiver that when you open the rifle to allow the upper to rotate up ( to access the BCG), the rail rests directly on the lower receiver. I haven't had any issues, but it's possible the rail could scratch the lower. I haven't put any rounds down range with it yet, but I'm not anticipating any issues. If there are I'll update this review accordingly.

Overall, I'm very pleased with this rail. You can spend another $30-40 and get a GunTec or other more well known brand, but they don't offer anything like this one. If you're wanting a slim quad rail (as opposed to a KeyMod or MLok), and not wanting to pay $400 for a Noveske RIS II (Also 2.25 inches wide), this is a great option.