What a 3D-printed shotgun caddy is and why people make them

A shotgun caddy is a holder that attaches to the side or underside of a shotgun stock to carry extra shells during shooting. A 3D-printed version is made from plastic using a 3D printer rather than purchased as a finished product. People print their own because they can customize the fit to their specific shotgun model, choose how many shells it holds, and avoid the cost of commercial versions.

The caddy typically holds shells in a row or cluster, keeping them accessible without a separate pouch or vest. A 3D-printed design lets you adjust the shell diameter fit, the mounting method, and the angle of the holder to match your shooting style and gun setup.

Key Takeaways

  • You need a 3D printer (FDM or resin), a design file, and plastic filament or resin; most caddies print in 4 to 12 hours depending on size and printer type.
  • Free design files are available on Thingiverse and Printables; search for "shotgun shell holder" or "shotgun caddy" and filter by your printer type.
  • The caddy must mount securely to your shotgun without blocking the safety, trigger guard, or your hand grip, so test fit before final printing.
  • Post-processing — sanding, painting, and testing shell fit — takes as long as printing and determines whether the caddy works reliably in the field.

Finding and choosing a design file

Start by searching Thingiverse.com and Printables.com for "shotgun shell holder" or "shotgun caddy." Both sites host thousands of free designs uploaded by makers. Filter results by printer type (FDM or resin) and look at the file preview images to see how the caddy mounts and how many shells it holds.

Read the comments section on each design page. Other users report whether shells fit properly, whether the mount stays tight, and whether the design works on specific shotgun models. A design with 50 positive comments and no reports of mounting failure is safer than a newer one with no feedback.

read the STL file (the 3D model format). If you find a design you like but it doesn't quite fit your shotgun, many designers allow remixing — you can read the file, modify it in free software like Fusion 360 or Tinkercad, and print your version. This step is optional but useful if the original design mounts to a Mossberg and you own a Remington.

Preparing your printer and materials

For FDM printers (the most common type), you need PLA or PETG filament. PLA is easier to print but more brittle; PETG is tougher and better for a caddy that will take impact. Most shotgun caddies use 50 to 150 grams of filament, which costs $1 to $3 per caddy.

Load the STL file into your printer's slicing software (Cura, PrusaSlicer, or your printer's native software). Set the layer height to 0.2 mm for speed or 0.1 mm for detail. Use 100% infill or 80% infill with thick walls — a caddy that's too hollow will flex and let shells rattle loose. Print time typically runs 4 to 12 hours depending on size and printer speed.

For resin printers, follow the same process but use the printer's resin and exposure settings. Resin prints faster (2 to 6 hours) but require post-curing under UV light and careful handling of uncured resin. The finished resin caddy is harder and more precise but more expensive per print.

Finishing and testing the printed caddy

Once printing is done, remove support material and sand the caddy smooth with 120-grit sandpaper, then 220-grit. Pay special attention to any rough edges where shells will sit — a burr can scratch shells or cause them to jam. If you printed in resin, cure it fully under UV light before sanding.

Test fit shells into the holder before mounting it to your shotgun. Shotgun shells vary slightly in diameter by brand and load type. If shells fit too tight, sand the holes slightly larger. If they're too loose, the caddy won't hold them securely — you may need to reprint with smaller hole diameters or add a retention lip.

Paint or seal the caddy if you want it to match your shotgun or resist moisture. Spray paint designed for plastic works well. Let it cure fully before mounting.

Mounting the caddy to your shotgun

Most designs mount using adhesive (epoxy or contact cement), screws, or a combination. Check the design file description to see what mounting method the designer intended. If mounting with epoxy, clean the shotgun stock with rubbing alcohol first so the adhesive bonds properly.

Position the caddy on the stock and check that it doesn't block your safety lever, trigger guard, or your hand grip. Dry-fit it (hold it in place without glue) and shoulder the gun to make sure you can reach the shells and operate the gun normally. This step prevents a wasted print.

Once you're satisfied with placement, explore the adhesive or screws according to the design. If using epoxy, clamp or tape the caddy in place and let it cure for 24 hours before shooting. If using screws, drill pilot holes first to avoid cracking the plastic.

Common problems and how to avoid them

Shells falling out during recoil is the most common issue. This usually means the caddy is too loose or the retention lip isn't tall enough. If this happens, you can glue a thin rubber strip inside the caddy to grip shells, or reprint with tighter holes and a higher lip.

The caddy cracking or breaking off happens when it's printed too thin or mounted with only adhesive on a high-recoil shotgun. Use thicker walls (80% infill minimum), PETG instead of PLA, and combine adhesive with screws for mounting.

Shells not fitting at all usually means the design was made for a different shell size (2.75 inch vs. 3 inch) or brand. Check the design comments to see what shells other users report working, or measure your shells and compare to the design's hole diameter before printing.

Frequently Asked Questions

Can I print a caddy that holds shotgun slugs instead of shot shells?

Yes. Slugs are the same diameter as shot shells but slightly heavier, so the caddy design stays the same. The main difference is that slugs are less flexible, so the retention lip needs to be slightly taller to prevent them from sliding out during recoil.

What's the difference between printing in PLA and PETG?

PLA is easier to print and cheaper, but it's brittle and can crack if the caddy takes a hard impact or gets very hot in the sun. PETG is tougher, more flexible, and handles temperature swings better. For a shotgun caddy that will see field use, PETG is the safer choice, though it prints slower and requires higher temperatures.

Do I need to seal or waterproof the printed caddy?

Not required, but recommended. Plastic absorbs moisture over time, which can cause warping or degradation. A coat of spray paint or polyurethane sealer protects the caddy and makes it last longer, especially if you hunt in wet conditions.

Can I print a caddy that mounts to a picatinny rail instead of the stock?

Yes. Search for "picatinny shotgun shell holder" on Thingiverse or Printables. Rail-mounted caddies are less common than stock-mounted ones but work well on tactical shotguns. Make sure the design is compatible with your rail width (usually 20 mm or 22 mm).

How many shells should the caddy hold?

Most designs hold 4 to 8 shells. Holding more than 8 makes the caddy bulky and unbalanced; holding fewer defeats the purpose. Choose based on your shooting style — clay shooters often prefer 6 to 8 shells, hunters typically use 4 to 6.