Sky's Halo airsoft projects (WIP)

[SkywardSoul117]

Hello Hello, 

I remembered I had an account here and asked some questions some time ago related to these projects. I figured I'd do a bit of a project dump on what I've been up to. I'll use this thread for future additions, as I certainly have more planned as funds allow. 

 

 

The BR-55 and M7 SMG are near completion and are fully functional. Both need a few tweaks and some internal parts. I'd stopped both projects until January this year, and started both from scratch with the aid of my new printer, a Prusa XL (single head for now). Due to ill health, I had to stop work on the BR, having completed a lot of but not all of the physical aspects, and instead directed my attention to the design work for the M7. The M7 requires a lot less metal work (only cutting some rods and drilling about 4 holes in a 3x12 stainless bar, and a couple in the alu barrel mounting). Thus both are being worked on in parallel. I'm currently in the process of refining a few things. Needless to say, neither project has been particularly cheap. 

Credit to Kingdom of Airsoft and Perun for the original idea to use the ETU++ as a "DIY" solution. 

 

 

The BR-55 

 

 

A bit of a mix of The Halo 2, 3, and H2A designs, I went for a mix of aspects due to preference, and deepened the stock to allow fitment of a V3 gearbox. It weighs around 4.5KG unloaded, and is reinforced with 15mm stainless box section within the upper, and 12x3 stainless bar running down either side of the stock. There are various bits of metal rod where needed. Surprisingly it's pretty well balanced on the (very comfy) grip, and will stand on the grip alone unsupported. It's printed very solidly in eSun's PLA super tough. It feels very sturdy and there are no squeaks or wobbles. 

 

(old video where it's basically being held together by me, you can also see my H2A Marine helmet). 

 

 

1:1 to the "real" size. 

 

Guts: 

It uses a perun ETU++ hooked up to various microswitches for operation, and has a proper 3 position selector with a mechanical safety. This means no bullpup trigger bar and a snappy trigger. 

The round counter is fully operational, utilising Tachyon's solution with a custom graphics pack and modified sensor layout, removing the need for a "sock" on the end of the barrel. The round counter is reset by pulling back the charging handle. 

 

Manually (very, very carefully, I swear) removed the sensor and emitter from the board, applied heatshrink, and superglued to a saddle that straddles the hole I drilled in the barrel. 

 

Also contains compass and clock. Quite useful for timed games. 

 

The gearbox is a V3 LCT AK, with an airsoft-pro G36 chamber and 450 something-mm ZCI barrel. Sadly the ML bucking I used (60' macaron) has given me some issues, and will not lift a .25 without dropping 70+ FPS. Having attempted the usual fixes and various nubs, I'm at a loss. I have a psionic Tho-R on the way for both the SMG and BR, so touch wood that'll be an improvement. The airsoft pro chamber is nice in that it bolts directly to the gearbox, removing that as a variable for air leakage. 

 

 

The battery compartment is in the foregrip, with an AK dust cover style button for easy access and removal. The space is sizeable, and I can't see much trouble fitting at least a 3000mah 11.1v in there (if only I had one). I intend to include a small toolkit.

 

The magazines are fully custom, with ML superfeed springs (hello midcap syndrome). Not perfect, but I'm working on improvements. Thanks to Igniz for some pointers on dimensions. I intend to try integrating AR mag hi-cap guts at some point for a skirmish mag. The mag release is situated in front of the mag well, and gives a nice satisfying click on seating. The well is intentionally loose for the addition of velcro, giving a secure fit. These feed into a modular feed block that interfaces between the chamber and magazine. I've allowed provision for a built in tracer and a mechanism to prevent BBs from dropping. 

 

 

Takedown: 

Basic takedown is very simple and tool-less. It involves removing the foregrip, removing a detent pin from in front of the trigger guard, then sliding the upper forward out of the 1/3 rifle length grooves. The braided battery cable should slide free easily. Removing the gearbox requires removing the hop from the gearbox, pulling the squished wires out, unscrewing 5 bolts on the back, and feeding it out through the open hole in the back of the stock, followed by disconnecting the deans and microswitch cable. Somehow both better and worse than the AUG. 

The pistol grip is held in by 6 M4 bolts and I doubt that'll ever go anywhere. Printed and oriented for maximum strength. The entire upper takes down into sections from around the 15mm tube. 

 

Other nifty details and gaffes: 

-There are 6 QD sling points, 2 rear, front and mid (in front of the receiver). 

-Rubber (TPU) butt pad and coating for the cheek rest. 

-The cheek rest is too far forward to comfortably use. Game design moment. 

-The rail is too far forward for most magnified optic's eye relief to be useful. You can however lift the stock over your shoulder to get close enough. 

-I neglected to put a ledge on the front of the trigger guard, which the fire select detent mechanism attached to. This meant if you put pressure on the trigger guard (say with your hand), it would move the fire select lever up and down. This has been rectified quite easily, if a little wastefully. 

-I dropped the whole lower receiver onto a concrete corner from several feet while carrying it to the food dehydrator to cure, after the final coat. I nearly screamed in anguish. Thankfully, PLA-ST is very tough, and it sustained only a minor dent on an edge. This is the first battle damage. Remarkable material for being so cheap and easy to print. 

-I originally intended the design to keep the hop up chamber with the upper upon disassembly. I found that no matter the spring used, firing would cause the hop up to move forward 5mm with every shot. I suspect this has something to do with the anti double feed mechanism it has. It's now fixed to the gearbox, and is somewhat delicate when unsupported by the upper, hanging by only a grub screw. At some point I'll look at fixing it proper to the lower. 

-The magazines had to be angled forward to be in an optimal position to feed. 

-I didn't think my power wiring through very well, and it's a bit of a rat's nest. The excess power wires that give sufficient length for the gearbox to be removed have to be stuffed into a hole to keep them out of the way. Not an easy prospect with thickly insulated 14awg wires. Needs improvement. 

-The muzzle flash is printed and currently just friction fits on the barrel. I've the means but not the expertise to use a lathe to cut a thread into it. When that happens, I intend to buy Foundry's alu flash hider. 

-The painting was a bit of a nightmare, and contained a lot of stops, starts and bad farts . Accidentally wiping off paint with unintentionally strong spirits, gray overspray onto black, clear clouding, dropping final piece onto concrete... etc. 

-The detail lines on the stock were so shallow, sanding and spray putty almost removed them in places. Without thinking I set to with a knife, butchering some grooves into several hundred hours of work. 

-Much like an old warplane being restored with a few bolts or a nameplate being the "same plane", the foregrip was the only part that made its way over from the original project. Considering the detail lines were so small that they didn't even print, I'm kind of wishing I hadn't. 

 

I'd say the (almost) end result is worth it though. 

 

 

 

 

M7 SMG

 

 

Ah, the first proper CAD project I ever worked on, and the first airsoft gun I ever attempted. Frankly, the original I started 5-6 years ago was unsalvageable. Looked pretty, but holy moly, what a mess. It's not wasted though, you learn things. I have to say I'm quite happy with how this one turned out. Far less faff than the BR-55, almost everything worked as intended without much trouble. Printed in much the same fashion and material, but a fair sight simpler. 

 

(please excuse the mess, Prusa XL enclosed in the background)

 

 

The guts: 

 

JG Vz.61 AEP innards form the working part of this pew pew. Regrettably, AEP performance isn't always the best, and repairing broken ones can be iffy. You can imagine my disappointment when I finally finished a gun that's been 5-6 years in the making, and it has an effective range of 15 feet. The stock bucking applies no backspin at all. Thankfully everything else works, and I have a Psionic Tho-R on the way to help remedy that. 

The gearbox unfortunately had an incident where the cut-off switch fell off internally, as evidently no thread lock was applied at manufacture. Awaiting a fine torx set to get at it. 

The feed route is an interesting one, given it goes around 4 bends and finally ends up vertical. Works just fine though apparently. 

 

(Note it's a little more noisy than it would be, as there's no barrel or hop unit, or BB being fired)

 

 

As a salve for the disappointment that may be gripping some of you upon hearing the acronym "A-E-P", this gun's perfectly sized for a P* F2, and would require minimal design changes to adapt it for such. 

 

This gun also uses the Perun ETU++, and this time with some wire management (woo). I've got a very satisfying clicky electronic safety that uses magnets as detents, as I had no room to integrate a mechanical safety in the linear trigger. It's very ergonomic and easy to toggle with the trigger finger within the trigger guard. The ETU was intended for this project originally as a way of getting around the lack of semi cut off present on CMG gearboxes (CQB gun with no semi is as useful as a max joule sniper in CQB), but proved perfect for bullpups. The fire selector isn't in the most ideal of locations (under the magazine well), but it can be easily toggled with the off hand. 

 

The battery compartment is in the grip, and a cap comes off with the push of a button at the back. It can hold standard sized lipo batteries, preferably short ~1200mah 7.4v. 

 

I'm very pleased with the magazine seating / locking mechanism. It was a problem with the original. This time there's a hook very securely mounted to the back of the receiver. As you slide the magazine forward onto the tray, the hook falls into a groove in the magazine, and as the fore of the magazine seats into the mag well, the hook locks the magazine in the X axis as the mag catch locks it in the Y. You can jerk the gun around by the magazine only without play. Nice click too. 

 

Both the stock and foregrip change position. The stock extends by around 95mm, and locks securely with a 5mm stainless pin into a 12x3 stainless bar. The foregrip also locks with a metal pin, but into ABS+. It has no side to side play, but has a little forward and back play when deployed. I've decided it's negligible given it's minor and doesn't make a noise. The ejection port / charging handle also works smoothly, though it's not for thick or gloved fingers. 

 

The top iron sights are removable, to be replaced with a pic rail. Side and bottom rails can also be added. 

 

Takedown: 

 

A little more tool intensive than the BR-55 for basic takedown. 2 bolts allow the removal of the upper "cap", 6 more for the inner "block" which houses the hop up chamber, feed block and outer barrel. This slides forward off the nozzle and up. This allows the gearbox, pressured down by the upper cap, to be removed. 

 

 

Nifty details and gaffes: 

-The stock detent spring has been a source of frustration and fiddling. I've spent some time trying to get the spring mounted onto the pin block. To be improved. 

-The stock pad is TPU with ABS encased within to mount the 2 QD fittings (designed for single point slings only, unless the front is wrapped with something). TPU doesn't deal with overhangs well, and the quality leaves something to be desired. I'm hoping a second head for the XL will solve this problem (multi-material integration). 

-The original Omron SS-5 switch I bought for the trigger sounded *exactly* like a computer mouse. I couldn't stand this and instead bought some of the XSS-5 copies that actually feel more solid and sound better. 

-Surprisingly ergonomic, though the grip is less comfy than the BR. I didn't want to sacrifice the aesthetic too much. The sights are useful for airsoft even if you can only really look down them when holding the gun out like a pistol. You can still align them while shouldered. Adequate for lobbing small plastic balls at other nerds. 

-The suppressor seems a little pointless for an electric gun, but I'll likely do it anyway at some point. It's very janky and intended to use an olight key ring torch with a threaded "presser" on the back to turn it on. I'd rather do it when I can thread the barrel. It'd also be more useful for a HPA version. 

 

Man I love the aesthetic of this thing. 

Drawing a blank here, nothing much went wrong. I'd hate you less for wanting me to make you one of these. 

 

That's about it for now. You may have noticed a new helmet in one of the pics, with built in forehead / glasses fan. Future projects will be the HPA SMG when I'm not poor (gee I wonder where the money went), Mk23 M6C Socom, and a HPA MA5B. We don't talk about the WE tech Glock I turned into a magnum. Needless to say I don't like WEtech anymore. I'd love to daytona a Halo replica, but alas, money. Ask away, just be aware I'm a little closed on specific details as I do plan to make a little money on these. 

Cheers for reading. 

 

 

Edited September 4 by SkywardSoul117
format errors, credit edit

[SkywardSoul117]

Quick update, I fixed the AEP gearbox and cleaned the factory earwax grease out. I don't hold much appreciation for the engineer that designed the gearbox, as it was quite a nightmare to reassemble. With a fully charged 7.4v and barrel installed, I think it sounds rather nice for an AEP. 

 

 

 

A quick shooting test gave me an indication that it should give surprisingly decent range with 0.25 or 0.28 BBs. I suspect the soft foam "nub" is causing inconsistent hop to be applied, so I'll be modifying the arm to accept an omega or H-nub tomorrow. Hoping it's not an air-seal problem. 

 

 

 

Edited September 5 by SkywardSoul117