M4 Stock Adjustment Lever + Locking Pin

Designed an Adjustment Lever + Locking Pin for a standard M4/AR15 stock.  The inspiration for this came from someone commenting on my Adjustable Stock model and asking why I didn’t include a 3d printed version of the pin and lever that the stock uses to be adjustable.  The lever was easy to make work but the pin was rather difficult given that there is a lot of spring tension on the pin when it is attached to a buffer tube.  A printed pin is rather weak at that size (~5.5mm diameter) and the pin kept snapping in half when trying to adjust the length of pull.  I solved this issue by splitting the pin in half the long way and then gluing it together once printed.  This changes the layer line orientation which is necessary for it not to immediately break in half.  It must also be printed at 100% infill as I had a few break from tensile stress when using 50% infill.

 

I used PETG for this but I believe PLA+ will be the best filament for this model since it has the higher tensile strength than most filaments. Someone will have to test and let me know though as I don’t have any right now.  Wasn’t able to make a printed spring as it just isn’t really possible for this configuration.  It will just snap every time you try to install it and there would have to be a lot of internal changes to make a printed spring possible.  The standard adjustment lever spring has a ~5.75mm ID and is 25mm long.  You can source these in spring kits on amazon or at local hardware store.  This set will also fit onto my custom made stock which is very similar to a standard adjustable stock so check that model out as well!  I’ll have some pictures below of how to install everything.  Enjoy!

 

Boost MeShow me some love on this model or one of my others.  Your support keeps me motivated!MembershipStarting this commercial license for anyone that wants to sell my prints and/or donate to my page.  This will help me purchase more filament for prototyping new designs!  Big thanks to everyone who helps support my page, I will be uploading more designs soon!

 

 

 

Instructions:  Use a light amount of glue (preferably superglue/gorilla glue) on one of the halves, then press them together and thread on the nut.  Allow the glue to dry, then unthread the nut and install onto stock!