Wow that is cool
I posted this on another thread but received enough questions that I needed to update and make it a bit more visible. (Firearms are wearing registered sears)
I got bit by the HK bug early on and finally picked up a DJ Getz clone about 4 years ago. I had specific requirements for a forearm and couldn't find anything that met my objectives. So in the absence of a solution I decided to make my own. I was fortunate enough to have some great experience with forum members and over time my desire for a forearm turned into a desire for a modular front end and just kept evolving.
Instead of an add-on accessory, what you see is actually a functioning component of the firearm since it houses the cocking tube support. This (current) design won't fit on legacy platforms with a permanently installed cocking tube because I wanted to be able to change the overall length of the cocking tube on my platforms. The main reason I went this route was for the modularity I desired both from the firearm and from the front end. The number of variations is somewhat overwhelming but exactly what I was aiming for. I'm working on another version that will encompass existing cocking tubes.
For the time being, my range time has validated that I'm pleased with what I have in hand:
- 6061-T6 Aluminum extruded, machined and hardcoat anodized by an aerospace/defense company
- M-LOK mounting surfaces at the 3, 6, and 9 o’clock positions
- Machined mounting surfaces for add-on rails of any type at the 2, 5, 7, and 11 o’clock positions (My preference is for Parker Mountain Machines rails)
- Retention via 2 cross bolts compressing around the trunion and receiver, so a quick-change setup that is extremely solid with no rotation whatsoever. I’ve got a lever-release mechanism on the drawing table for the rifle version.
- Low profile full-length Pic rail the entire length of the firearm. Because of the design adaptability I’m entertaining different rail accessories over the receiver section.
- Front end completely open for any attachment approximately 1.5 inches in diameter, since I wanted to be able to use this on a future SD build as well.
A lot of thought and planning went into the design and it continues to evolve:
- Ability to be used on “legacy” platforms with rolled receivers. Heavy emphasis was placed on ensuring there would be no legal issues. I adapted the forearm around the platform instead of creating a new platform that could not be used with registered sears.
- Ability to quickly install a forward rail extension. The inner diameter allows a user to attach a suppressor since I wanted to be able to cover that with a rail and increase mounting surface for accessories at the same time.
- Ability to be used on all roller-lock platforms. This originally started life as a design for a 21E/23E build but quickly morphed into something much larger.
I have not been disappointed in the ACR stock at all. The stock height for me is perfect since it gives me a solid cheek weld with almost every rot dot or scope I run. The pictured stock adaptor was 3D printed but I’ve got a batch coming back from the aerospace/defense company that are aluminum and oh so pretty.
I'm still working on a lot of advancements and capabilities so this is by no means a finished product. It will never be "perfect" but I have no problem pursuing that goal! This isn't confined to the MP5 since I love all the roller locks and my goal is to evolve them all to the absolute best they can be without compromising the reliability we all know them for.
Always open to thoughts, suggestions or feedback and remember that this is just the tip of the iceberg. I'll post more photos of a few more projects soon. Anyone want to know what you can do with a removable front end, quality components from RCM and an industry partner that tests on equipment that exceeds standards set by NSW Crane Division? Those of you who are going to the DFW shoot with paul123 will get a first hand look before anybody else...
Wow that is cool
Qualified HK Sear
Black Ops Defense mp5