Is this 3D model free to download?

Yes, Nerf Caliburn - Top-Off Magwell is free to download from Thingiverse. Open it in the free Thinger app, or use the "Download from Thingiverse" link to open the original listing by the creator.

Where do I download the STL file?

The download is hosted by Thingiverse. Use the "Download from Thingiverse" link on this page to open the original listing and grab the file, or save it to your print queue in the free Thinger app.

Designed by captainslug, published on Thingiverse. Please credit the creator when sharing your print.

Can I print this at home?

Yes. This is a printable 3D model intended for home FDM and resin printers. Check the original listing for suggested print settings.

Nerf Caliburn - Top-Off Magwell 3D printable model by captainslug

Nerf Caliburn - Top-Off Magwell

Source: Thingiverse by captainslug

The Nerf Caliburn - Top-Off Magwell is a free printable 3D model from Thingiverse by captainslug. An old-style magwell but allows for magazine to be topped-off with darts when the breech is open. You can download the STL file from the original listing below and print it at home.

Open in Thinger (free) Download from Thingiverse

84 saves Source: Thingiverse Updated 2026-10-09 License: CC-BY-NC · non-commercial Category: Toys & Games

Tags: caliburn, nerf, nerf caliburn

About this model

An old-style magwell but allows for magazine to be topped-off with darts when the breech is open. This is accomplished by moving the inserted position of the magazine DOWN by 1/8 of an inch. So I'm not currently sure if this will be compatible with every aftermarket mag or mag adapter that exists. I really only intended to use this with straight-18 mags so as to avoid having the carry any spare mags. This requires all of the included parts and is NOT COMPATIBLE with the takedown function. So you will need to review the older revisions of the instructions for the first few pages of the assembly.

Frequently asked questions

Is this 3D model free to download?: Yes. Nerf Caliburn - Top-Off Magwell is free to download from Thingiverse. Open it in the free Thinger app, or use the "Download from Thingiverse" link above to open the original listing.
Where is the STL hosted?: The download is hosted by Thingiverse, not by Thinger. We link you directly to the original listing by captainslug.
Who made this model?: Designed by captainslug, published on Thingiverse. Please credit the creator when sharing your print online.
Can I print this at home?: Yes. This model is intended for home FDM and resin 3D printers. Check the original listing for suggested print settings like layer height and supports.