Your speargun is the one piece of gear that most directly decides whether you swim home with dinner or with a story about the fish that got away. Yet it's also where new spearos make the most expensive mistakes, buying too much gun, too little gun, or the wrong power system entirely for the water they actually dive. This guide breaks down the two dominant power types, how to size a gun to your environment, and how to match it to the fish you're hunting, so your first (or next) purchase earns its place on the boat.
Band vs. Pneumatic: Two Ways to Launch a Shaft
Nearly every speargun on the market drives the shaft with one of two power sources: stretched rubber bands or compressed air. Both put fish on the stringer, but they behave differently in the water and demand different maintenance habits.
Band-Powered (Sling) Spearguns
A band gun, sometimes called a sling or rail gun, uses one or more loops of latex rubber stretched from the muzzle back to a notch on the shaft. When you release the trigger, the bands contract and fire the spear. The appeal is mechanical honesty: there's very little to go wrong, you can see exactly how much power you've loaded, and a broken band is a two-minute fix on the boat if you carry spares. Band guns also come in the widest range of lengths and configurations, and most of the spearfishing world, including dive shops and charter crews, is built around them. That means parts, advice, and replacement rubber are easy to find.
Pneumatic Spearguns
A pneumatic gun stores energy as compressed air inside the barrel. You load the shaft against that air pressure, and releasing the trigger lets the air drive it forward. The payoff is power density: pneumatic guns deliver serious punch in a shorter, more maneuverable package, which makes them a favorite for hunting in caves, holes, and tight structure. There are no bands to perish in the sun, and many models let you adjust power. The trade-off is complexity. Seals and internal components need occasional servicing, and field repairs are harder than swapping a band.
Which Should You Start With?
For most divers building a first setup, a band gun is the more forgiving choice. It's simpler to maintain, easier to get serviced or repaired, and the surrounding support network is deeper. Pneumatic guns are excellent tools, particularly for reef hole-hunting where a compact, powerful gun shines, but they reward divers who already understand their local conditions and don't mind a little extra upkeep. If you dive tight structure and value a short, hard-hitting gun, a pneumatic like a regulated model is worth a serious look. If you want versatility and low-fuss ownership, start with a sling.
Sizing Your Speargun by Dive Environment
Length is the single most important spec after power type, because it dictates both your effective range and how easily you can track a moving fish. The water you dive should drive this decision far more than the size of the fish you dream about. A gun that's too long in murky water becomes a liability; one that's too short in the blue leaves you out of range.
Short Guns: 50–75 cm
Short guns excel in low visibility, kelp, and reef structure where fish hold close and you need to swing the muzzle quickly in confined space. In green, silty, or heavily structured water, you rarely see fish beyond a few feet anyway, so the compactness matters more than reach. These lengths are also popular for pneumatic hole-hunting and for smaller reef species.
Mid-Length Guns: 90–110 cm
If you're not sure where you'll dive most, this is the range to buy. A 90 to 110 cm gun is the most popular starting size for good reason: it delivers an effective range of roughly three to four meters, enough to land quality reef fish and smaller pelagics, while staying maneuverable enough for all-around use. For the majority of recreational spearos diving mixed conditions, a single- or double-band gun in this window is the sweet spot.
Bluewater Guns: 120 cm and Up
Clear, open water and larger pelagic targets call for length. Longer guns store more band energy, push heavier shafts, and reach farther, which is exactly what you want when visibility is high and fish stay wary at distance. These are specialist tools, though. In anything but clean water they're cumbersome, so treat a bluewater gun as a second purchase once you know you'll be hunting open ocean.
Matching the Gun to Your Ability and Target
Power and length should also scale with the fish you realistically pursue and the breath-hold you bring to the dive. Bigger fish need more penetration and a heavier shaft, which means more bands or higher pneumatic pressure, but that same power makes a gun harder to load and slower to aim. Beginners are almost always better served by a gun that's easy to load and point accurately than by one that's overpowered. Accuracy lands fish; raw power just makes a miss travel farther. Be honest about your current freediving depth and comfort, and let the gun grow with you rather than buying for the diver you hope to become in three seasons.
In-Stock Speargun Picks from DiveCatalog
Here are current, in-stock guns that map cleanly onto the categories above. You can browse the full lineup in the Spearguns collection or narrow to band models in the Sling Spearguns collection.
Compact sling for tight water: The Seac Polpone Sling Speargun is a short, spring-loaded gun built for maneuverability in confined spaces, a practical entry point for reef and structure hunting.
Versatile all-rounder: The Seac New Sting Sling Speargun comes in multiple lengths and handles tight spaces with straightforward loading, making it a sensible first band gun for divers testing different conditions.
High-performance bluewater sling: The SEAC Fire Sling Speargun uses an open muzzle for twin 14 mm circular power bands and a removable rubber grip, built for divers who want range and punch in clearer water.
Regulated pneumatic for hole-hunting: The SEAC Asso C/R Pneumatic Speargun pairs an anodized aluminum barrel with a soft ergonomic grip and adjustable power, a compact, hard-hitting option for divers who work caves and structure.
Beyond the Gun: Completing Your Setup
A speargun is only as effective as the diver behind it, and a few supporting pieces make a real difference underwater. Long freediving fins move you efficiently on a single breath and help you close distance quietly, so it's worth browsing purpose-built options in the Spearfishing Fins collection. A low-volume mask that's easy to equalize and a camo or open-cell wetsuit for warmth and concealment round out a serious kit; the Spearfishing Wetsuits collection covers the exposure side. You can see everything in one place in the broader Spearfishing collection.
Safety and Handling Essentials
Spearguns are effective hunting tools, which means they demand respect out of the water as much as in it. Only load your gun in the water, pointed away from yourself and everyone else, and never swim toward the boat or another diver with a loaded gun. Keep your trigger finger off the trigger until you're aimed at a fish and certain of what's behind it. Always dive spearfishing with a buddy, use a float and dive flag to mark your position for boat traffic, and know your local regulations on species, size limits, and gun restrictions, which vary widely by region. Rinse the gun in fresh water after every session, inspect bands or seals for wear, and store it unloaded and out of direct sun. Treated well, a good speargun will hunt reliably for many seasons.
Choosing a speargun comes down to three honest questions: How's the visibility where I dive, what am I hunting, and how much maintenance do I want to take on? Answer those and the right gun almost picks itself.
