Mossberg OPSOL Mini Clip
The OPSOL Mini Clip is a simple polymer adapter that installs in minutes into Mossberg 500 and 590 shotguns, allowing them to reliably feed and cycle 1-3/4″ mini shells. Without the Mini Clip, most pump shotguns fail to reliably cycle mini shells because the short shells can tip and jam in the loading port. With it installed, Mossberg 500 and 590 owners gain 2–3 additional rounds of capacity over standard 2-3/4″ shells, significantly reduced felt recoil, and faster follow-up shots — all without modifying the shotgun.
Read our OPSOL Mini Clip Guide ↓
How It Works
The OPSOL Mini Clip is a drop-in polymer piece that sits in the loading port of compatible Mossberg shotguns. It functions as a shell stop that prevents the short 1-3/4″ mini shells from tipping during the feeding cycle — the primary failure mode when running mini shells without the adapter. Installation requires no tools and no modification to the shotgun. The clip snaps into place and can be removed just as easily when you want to return to standard shells. It’s compatible with Mossberg 500, 590, 590A1, and Maverick 88 platforms.
Mini Shell Benefits
Aguila 1-3/4″ mini shells are the most popular mini shell on the market and the round the OPSOL was specifically designed around. A standard Mossberg 500 with a 5-shell tube magazine holds 7 mini shells instead of 5 standard shells — a 40% capacity increase. The reduced powder charge produces significantly less recoil than full-power 12 gauge loads, making the combination popular for new shooters, recoil-sensitive shooters, and anyone running high round counts in competition. Mini shells are available in buckshot, birdshot, and slug configurations from Aguila.
Compatibility
The OPSOL Mini Clip is specifically designed for Mossberg 500, 590, 590A1, and Maverick 88 shotguns. It is not compatible with Remington 870, Benelli, Winchester, or other pump shotgun platforms — those designs have different loading port geometries. OPSOL offers a version for the Mossberg Shockwave as well. Always confirm your specific Mossberg model is compatible before ordering.
Competition and Home Defense Use
In 3-Gun competition, the OPSOL/mini-shell combination allows a higher shell count without switching to a longer magazine tube, which can be a meaningful advantage in stages with high shotgun round requirements. For home defense, the combination provides more rounds in the gun with less recoil — useful for shooters who find full-power buckshot difficult to manage. The tradeoff is that mini shells produce less energy than full-power loads, so defensive users should confirm adequate penetration with their chosen mini buckshot load.
Related Pages
Browse our Mossberg 500 and Mossberg 590 pages for the shotguns this adapter fits. See all shotgun parts and accessories for other upgrades, and shotgun ammo for mini shell availability.
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