The Limited Assisted Reset Kabuto, or LARK - A printable 4-position Kabuto TURD mod. I engineered the disconnectors, cam, selector and mandrel. Big ups to Kabuto Firearms for making the FRT, this project would be impossible without their contribution!

This is a WIP but we own the rights to this content, except for the Kabuto T.U.R.D.

4/18/2026: Cam Geometries (both 3 and 2 round cams) changed to prevent interference between the edge and the receiver cut. Added a link for a good hammer spring that delivers the weight necessary after the cam cut for a good price, $12 for 3 ain't bad.

4/20/2026: Discos made more sticky. I am getting really good reliability on this update - no secret handshakes or bullshit about any sort of unreliability on my end at this time. I say this after TRYING to induce failures. It ain't happening. At most, post-processing at this point may include filing the kabuto timer a bit (you have an editor in the slicer file included, just use that), and maybe gently file the very tips of the disconnector catches if they're too sticky (by gently, I mean GENTLY. Tolerances in this area are within fifteen thousandths of an inch FWIW, so go slow and gently one disconnector at a time and do thorough functions checks with every filing. But yes, I think we're about locked in on a design here.

4/29/2026: Updated the Kabuto geometries to make function with the LARK more reliable, it now always functions regardless of selector setting. Disco geometries updated to reduce stickiness.**

https://youtube.com/shorts/VJNGX7ZoB3A

Instructions:

You will need to secure some 18 gauge copper wire for the clutch, I have a video on how to make that. Go check that out!

2-hole trigger:
https://strykegunworks.com/shop/firearms-parts/ar-15/ar-15-trigger-milspec-curved-black/

This link has the appropriate trigger that you'll need with the two disconnector spring pockets, GUARANTEED.

Extra power hammer spring suitable for cutting (the cam needs room obviously):
https://ghostinc.com/ghost-ar-15-lr-308-30-extra-power-flat-wire-hammer-spring-red/

You will also need a second disconnector spring (obviously), here:
https://ar15discounts.com/products/mil-spec-ar-15-disconnector-spring/

In a pinch, a cut pen spring will also work - I've tested this myself.

When installing the selector, use a flathead screwdriver to depress the disconnectors, or install the disconnectors AFTER the selector, and set the selector to the 4th position when you do (fully rotated away from safe)

Necessary modification: you will need to cut your hammer spring as shown in the zip folder images to make room for the components on the right side of the hammer. I recommend getting an enhanced power hammer spring to compensate for the poundage drop that results from cutting half of the spring away. Until an updated cam is made that allows A2 burst-compatible hammer springs to be used, this modification is necessary.

As well: included is a 3MF with a few modifiers: I needed to remove material from the kabuto to make it fit into my receiver. The modifiers can be removed and an included pair of pins exists on the plate - one for each frame size. If your receiver takes the unmodified frame, delete the modifiers and use the larger pin.

Use tree supports on parts like the selector or anything with overhangs.

For information about licensing/production for commercial purposes, read the readme file included. Terms extend to any mods and extras we produce on this project. Please make as many of these as your heart desires but hit us up if you intend any business with it - if you're eating off our work, we ask you give us a cut.

I sincerely hope you enjoy and help make rapid safeties COMMON USE. Give the devil no foothold to disarm us any further, ever again. Be the example and the solution, and don't be a problem!

Support me on by purchasing from my store:
https://strykegunworks.com/ - I would appreciate if you buy something to support the project! I love you <3

Note: This is a Collaboration Project with Stealth the Unknown.
His Link to the Project Can be found here: https://odysee.com/@Stealth_The_Unknown:7/LARK-Kaboodle:3

LBRY Tags: 3 round burst; burst frt; forced reset trigger; 3d printing; guncad