What Gauges Do Shotguns Come in, and What Size Should I Use for Hunting?

Picking the right shotgun gauge can mean the difference between a clean kill and a missed opportunity. From chasing mallards on the Mataura to walking up pheasant in Canterbury, the gauge you shoot affects recoil, pattern density, ammo availability, and how comfortable you are after a full day in the field.

So, how many gauges of shotguns are there, and which one should New Zealand hunters be using? Let’s dive into it.

How Many Gauges of Shotguns are There?

In practical terms, there are six. The 10, 12, 16, 20, 28, and .410 bore are the standard gauges commercially available today. Historically, gauges have ranged from 2 to 50, but most have long since disappeared.

The gauge system itself is a bit old-school, based on how many lead balls of the bore’s diameter it takes to weigh one pound. A 12-gauge barrel fits a lead ball, where 12 of them would equal a pound. A lower gauge number means a larger bore. The .410 is the odd one out, measured by its actual bore diameter (0.410 inches) rather than the gauge system.

The 12 Gauge

Of all shotgun gauges, the 12 gauge is the undisputed all-rounder, and by far the most popular in New Zealand. There’s a good reason for it: it handles virtually any hunting application you’d use a shotgun for.

With the widest range of ammunition available, from light target loads to heavy waterfowl steel, a 12-gauge lets you chase ducks in the morning and walk up quail in the afternoon with the same firearm. It delivers dense, powerful shot patterns at effective hunting ranges.

The trade-off is recoil. A standard 12-gauge field load kicks noticeably harder than smaller gauges, and after 50-odd shots on the maimai, your shoulder will know about it. However, modern semi-automatic and gas-operated actions absorb a good chunk of that recoil. Fish & Game NZ recommends the 12-gauge for waterfowl hunters, noting the wider range of guns and ammunition available in New Zealand.

The 20 Gauge

When people ask what gauges do shotguns come in for upland hunting, the 20 gauge is near the top of the list. It’s the second most popular shotgun gauge and has gained serious ground among NZ hunters. It’s lighter, kicks less, and swings faster than a 12 gauge, making it a favourite for upland hunting where you’re carrying your gun all day.

Modern 20-gauge ammunition has closed the performance gap significantly. Factory loads now push 36-gram (1 ¼ oz) payloads that match the shot weight most hunters use in a standard 12-gauge field load. For waterfowl hunting over decoys at moderate ranges, a well-choked 20-gauge is more than capable.

It’s an excellent option for younger or smaller-framed shooters who find a 12-gauge uncomfortable, building confidence without the flinch that heavy recoil can cause.

Other Gauges Worth Knowing About

With 12 and 20-gauge shotguns out of the way, here’s a quick rundown on the four less common options:

• The 10 gauge sits at the heavy end. It was once the go-to for long-range waterfowl, but improvements in 12-gauge magnum loads have made it largely redundant. The guns are heavy, the ammo is expensive, and availability is limited in NZ.

• The 16 gauge takes up an awkward middle ground between the 12 and 20. Ammunition is harder to source in NZ, and gun options are limited. If you already own one, it’s a perfectly capable hunting tool, but if you’re buying new, a 12 or 20-gauge makes more sense.

• The 28 gauge is a lightweight, low-recoil option loved by experienced shooters who want a challenge. It’s effective on small game and upland birds at closer ranges, though ammo availability and cost can be limiting factors.

• The .410 bore fires the smallest payload of any standard shotgun. It’s often chosen as a starter gun for young shooters or for pest control. The thin shot pattern and limited range make it a poor choice for serious hunting.

Which Gauge Should You Choose for NZ Hunting?

What gauges do shotguns come in that actually suit our local conditions? For most hunters, the decision comes down to 12 or 20 gauge.

If you’re primarily a waterfowl hunter chasing ducks, paradise shelduck or swan, the 12 gauge is hard to beat. It offers the payload and pattern density needed for birds at range, as well as the widest selection of non-toxic ammunition (now mandatory for all waterfowl hunting in New Zealand).

If upland hunting is more your style, a 20-gauge offers a lighter carry and a faster swing without sacrificing practical performance. And remember, lead shot is still permitted for upland game, so you’re not limited to steel loads.

For hunters who do a bit of everything, a 12-gauge with a selection of different loads covers the broadest range of hunting scenarios. But consider physical comfort too. A gun you shoot well and shoot confidently will always outperform one that’s technically “more powerful”.

Find the Right Shotgun Gauge at Shooters World Gore

Still weighing up which gauge suits your hunting style? With how many gauges of shotguns there are, it can get confusing. Our firearms specialists at Shooters World Gore can match you to the right one based on your experience, the game you’re chasing, and the conditions you hunt in.

We carry a range of gauges and action types from trusted brands, all backed by great prices and personalised service. Explore our shotguns for sale online or visit us in-store for hands-on advice from real hunters who understand New Zealand conditions.