Mossberg 500 20 Gauge
Model: 50136
Mossberg 500 20 Gauge
Model: 50136
Full Specifications
About This Firearm
The Mossberg 500 is one of the most heavily customized pump shotgun platforms in America, and that's the main reason to consider it. The 20 gauge field version carries 6+1 in a 45.5" gun weighing 112 oz — more shells than the Remington 870's 4+1, which matters during a long dove walk or a second flush in the grouse woods. The aluminum alloy receiver keeps weight reasonable for a field gun, and the top-tang safety is truly ambidextrous, which the 870's right-hand-biased cross-bolt safety isn't.
Buy the Mossberg 500 if you want a 20 gauge pump with a large parts and accessory ecosystem, or if you plan to swap barrels between hunting and clay applications. Skip it if you want the smoothest possible action out of the box — the 870's steel receiver cycles slicker out of the box, and a new 500 sometimes needs a few hundred shells before cycling becomes effortless. The 26" vented rib barrel is a standard upland length; if you hunt waterfowl or need more swing, a 28" barrel is a straightforward swap.
Best For
Strengths & Limitations
- 6+1 capacity is 2 rounds more than the Remington 870 Express, which adds up during multi-bird flushes without reloading.
- The top-tang safety works the same way for left- and right-handed shooters — a real advantage over cross-bolt designs for households with mixed-handed users.
- Barrel swaps are fast and the aftermarket is broad. A dedicated turkey or deer barrel costs around $150-200, and the receiver accepts them without gunsmithing.
- The aluminum receiver feels less substantial than the 870's milled steel receiver — a trade-off for lighter weight, but something owners notice when handling both guns.
- New 500s sometimes have a stiffer action than expected. Most owners report it loosens up after a few hundred rounds, but the 870 tends to cycle smoother straight from the box.
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Frequently Asked Questions
What's the first upgrade most Mossberg 500 owners make?
Community consensus points to a barrel swap first — either a 28" barrel for waterfowl and longer crossing shots, or an 18.5" cylinder-bore barrel if the owner also wants a utility or home defense role. After that, most owners add a raised front sight or a fiber optic bead, since the stock dual-bead setup can be hard to pick up in low light. Neither upgrade requires any tools beyond a choke wrench.
Does the Mossberg 500 20 gauge use the same barrels as the 12 gauge?
No. The 20 gauge and 12 gauge 500 barrels are not interchangeable — the magazine tubes and receiver dimensions differ between gauges. A 20 gauge barrel will only fit a 20 gauge receiver. If you're buying a spare barrel, confirm the gauge before ordering, as the two versions look similar at a glance.
