Best caliber for hogs: what the published sources support

"Best caliber for hogs" draws strong opinions and very little evidence. We looked for what authorities actually publish: Texas A&M AgriLife, Texas Parks and Wildlife Department hunter education, SAAMI (the U.S. ammunition industry's standards body), and the national standard Australia uses for shooting feral pigs. Where writers disagree, we say who said what. This page doesn't rank rifles, and it doesn't pretend a cartridge can fix a bad shot.

What actually decides a clean kill

Texas A&M AgriLife's selective shooting guidance starts with placement: "Correct shot placement is important to ensure the process is quick and humane." It says shot placement on hogs is very similar to other large game, with one important exception. Boars carry a shield, a dense, tough layer of tissue under the hide over the shoulder. It protects them from other boars' tusks, "but it can also allow a pig to survive poorly placed shots with low caliber rifles." AgriLife's advice: "use a high caliber rifle just like you would when hunting other large game."

Australia's national standard for ground shooting feral pigs, NATSOP-PIG003 (Terrestrial Vertebrate Working Group, 2024), names the two things that matter most when choosing a firearm and ammunition: "Energy at the target and bullet construction." It requires expanding bullets (hollow point, soft point or polymer tip) and sets a simple rule for when to shoot: the pig is clearly seen, it's within the effective range of the firearm and load, and a humane kill is highly probable. "If in doubt, do NOT shoot."

On where to aim, TPWD's hunter education course says the broadside shot presents the largest target for the heart and lungs, just behind the shoulder, and that you should never take a shot at an animal facing directly away: wait for a better angle or pass. The Australian standard adds a hog-specific point: adult males' cartilage shield can interfere with frontal chest shots, so side-on chest shots are preferred. It also sets a skill bar worth borrowing: three shots inside a 7.5 cm (about 3 inch) group at 100 meters (about 109 yards) from a bench rest, and a solid rest in the field. Our roundup of shooting sticks and tripods covers the rest.

Put together, a clean kill has four parts: enough energy, a bullet built to expand, a heart-lung hit, and a shooter who has proven the rifle on paper first. The cartridge is one of the four.

Two published yardsticks

We found two published benchmarks that speak to cartridge choice for hogs. They come from different places and don't say the same thing, so we give both.

1. Texas A&M AgriLife: a rifle suited to other large game. No number, but a clear direction away from small calibers.
2. Australia's NATSOP-PIG003: a recommended minimum for ground shooting feral pigs of .243 inch caliber, an 80 grain bullet and 1,819 ft-lb of muzzle energy. Its examples of acceptable combinations (.243 with 80 grain, 25-06 Remington with 90 grain, .308 Winchester with 150 grain) each carry a maximum distance of 200 meters.

Be clear about what the second one is: an animal-welfare standard for pest-control shooting in Australia. It isn't U.S. or Texas law, and Texas sets no cartridge rules for hogs on private land (see the law section). We use it because it's the only published numeric minimum for feral pigs we found, and it gives you something concrete to measure a cartridge against.

Hunting writers also cite a rule of thumb of about 1,000 ft-lb of energy at the animal for deer-sized game (Jeff Johnston, American Hunter, 2018). Other experienced writers say they don't subscribe to it and care more about reliable bullet expansion (Philip Massaro, 2017). Treat it as a rough floor, not a finish line.

The common hog cartridges, by the numbers

These are reference loads from SAAMI's centerfire rifle standard (Z299.4-2025) or, where noted, a published source, with the energy worked out by the formula above.

Two caveats before you read too much into a single number:

• Test barrels aren't your rifle. SAAMI states that "there should be no expectation that these velocities can be duplicated from any test utilizing firearms," and that barrel length adds to the difference. Look up the maker's published velocity for the exact load, and expect a short AR barrel to land somewhere else.
• Muzzle energy isn't energy at the hog. The Australian standard talks about energy at the target. Every bullet slows with distance, and Massaro (2017) advises choosing a bullet that will still expand reliably at the farthest distance you expect to shoot.

Published opinion on .223 and 300 Blackout for hogs splits. Bryce Towsley, writing in American Hunter (2013), calls the .223 Remington and 300 Blackout "outstanding cartridges, but not for hunting hogs," and underpowered for serious, ethical hog hunting in his view. Philip Massaro (American Hunter, 2021) says the .223 can be a deer cartridge with a proper bullet, but that he has seen deer lost despite what looked like a well-placed shot, and that there are better tools for the job. RCBS, a reloading-equipment maker, claims supersonic 300 Blackout loads with controlled-expansion 110 to 150 grain bullets are effective on whitetail and hogs inside 200 yards (maker's claim). On the 6.5 Grendel, Massaro (2024) calls it fully capable on deer inside 300 yards. Our honest summary: the heavier cartridges give you more margin for the shot that isn't perfect, and the lighter ones ask more of your placement and your distance discipline.

Trap, feeder or open field: what changes

The same cartridge question has different answers depending on where the shot happens. We didn't find a source that assigns specific cartridges to each situation, so this table sets out what the published guidance says about each one instead.

The two matchups hunters ask about

300 Blackout vs 5.56 for hogs

Both run in an AR-15 at the same 55,000 psi SAAMI maximum average pressure, but the .223 and 5.56 push light .224 inch bullets fast, while 300 Blackout pushes heavier .308 inch bullets slower and was designed with suppressors in mind. By our math on published loads, their supersonic muzzle energies land close together, about 1,290 against 1,325 ft-lb. The full breakdown, including a chamber mix-up that can wreck a rifle, is in 300 Blackout vs 5.56 for hogs.

6.5 Grendel vs 300 Blackout for hogs

The Grendel fires a 123 grain, .264 inch bullet at 2,580 fps in SAAMI's reference load, about 1,818 ft-lb, roughly 37% more muzzle energy than a 125 grain 300 Blackout load by the same math, and it holds its energy better at distance. The trade-off is hardware: the Grendel needs a different bolt face than a standard AR-15, while 300 Blackout needs only a barrel change. The details are in 6.5 Grendel vs 300 Blackout for hogs.

Backstop, chamber and night safety

More hog-hunting mistakes come from these three places than from cartridge choice. Every item below comes from the source linked with it.

• Backstop and what lies beyond. TPWD's shooting safety rules: "Know what is in front of and behind your target. Determine that you have a safe backstop or background." Never shoot at animals on top of ridges or hillsides, never shoot at flat, hard surfaces such as water, rocks or steel, and know how far bullets can travel.
• Match the ammunition to the barrel marking. SAAMI says firearms should only be used with the ammunition designated by the maker, and to check the headstamp against the markings on the firearm. Its FAQ says it is not safe to fire 5.56 ammunition in a barrel marked .223 Remington.
• Keep 300 Blackout away from .223 and 5.56 rifles. RCBS warns a 300 Blackout round "will chamber in a .223 barrel but will cause a catastrophic failure when fired." The NRA Blog recommends dedicated, clearly marked magazines and separate, labeled ammunition containers.
• At night, the light doesn't show the whole danger zone. NATSOP-PIG003 notes the spotlight only lights part of where a bullet can go. It also says not to shoot from a moving vehicle, because accuracy suffers.
• Finish the job. The same standard requires wounded pigs to be found and dispatched as quickly and humanely as possible, and asks shooters who take a lactating sow to make reasonable efforts to find her dependent piglets. That is part of a clean hunt, not an afterthought.

What Texas law says

Hunting at night brings its own rules on lights, vehicles and protected game. They are covered in can you hunt hogs at night in Texas, and the full legal summary is in our Texas hog hunting laws guide. This is a summary, not legal advice; confirm with your local game warden.

The part we can recommend: the optic

Noble Research Institute's Josh Gaskamp notes that wild pigs are most active around dawn and dusk but can be active any time of day or night (Hay & Forage Grower, 2021). Low light is where the optic earns its place. Texas A&M AgriLife notes that pairing shooting with accessories such as thermal imagery or night vision lets managers remove the final hogs that dodged other methods. A thermal also helps with the safety rules above: the Australian standard suggests using one to check the area for risks before a shot.

What to check on a thermal scope for a hog rifle, whatever the cartridge:

• A published recoil rating. Makers state it differently (joules, g-force, or a named cartridge), and some don't publish one at all. Pick a scope whose maker rates it for your rifle.
• Lens and base magnification for your distances. A wide, low-power view is faster at a feeder; a bigger lens shows more detail across a field.
• Battery for a full sit, and a way to hold separate zeros if the scope moves between rifles. Our guide to zeroing a thermal scope covers the zero itself.

For the full field of thermal options across every budget, see our ranking of the best thermal scopes for hog hunting.

A caliber isn't hog control

No cartridge solves a hog problem on its own. AgriLife describes selective shooting as a great way to finish off a sounder that trapping only partly removed, or to act when hogs first show up in small numbers. The numbers explain why: Texas A&M's Natural Resources Institute estimated in 2019 that about 66% of the population would have to be removed every year just to stop it from growing (Texas A&M NRI, 2019). Our explainer on how fast feral hogs reproduce works through that math, and the plan for combining trapping, shooting and exclusion is in how to get rid of feral hogs. For everything else on control and the rules, start at our hog control hub.