Big-bore airguns have been around since the 1600s, but the past couple decades have seen a growing interest and significant development in the technology. Lewis and Clark carried a big-bore airgun on their Western explorations, but knowledge of these guns seemed to evaporate until recently.
It was during the early 2000s that big-bore airguns built by an innovative craftsman named Dennis Quackenbush trickled into the market. These early rifles were available in .308- and .50-caliber, with the .457-caliber eventually becoming the most popular caliber in the line. I met Dennis in 2002, and along with Eric Henderson started using these rifles for hunting predators, wild hogs and exotics in Texas. In 2003, I used three Quackenbush rifles on my first hunts in South Africa.
The guns I carried were the most powerful air rifles available at the time, including a .50-caliber that had been modified to generate 450 foot-pounds of energy. This represented a marked increase in the out-of-box specification for the rifle at that time, and I took kudu and several other species of plains game with it.
Increasing Popularity
Over the years, as interest in big-bore airguns increased, manufacturers introduced increasingly powerful guns to market. At first these were small scale production runs, but as interest surged and hunting regulations in many states evolved to allow the use of these gun, larger and more established manufacturers jumped in, and something of an airgun power race began.
In the balance of this article, I am going to share information on three of the most powerful production airguns currently available. In the spirit of full disclosure, I will say that these might not be the most powerful airguns on Earth — there are custom guns and hotrod tuners modifying guns — so it is always possible that higher power outputs might be achieved. I would also mention that in my view, the most powerful does not equate to the best, in and of itself. The accuracy, shot count, consistency, reliability, ergonomics along with other criteria should be taken into consideration when choosing a rifle to meet individual needs.
All these big-bore air rifles utilize a pre-charged pneumatic design that is powered by a high-pressure air charge. The rifle will have an on-board storage tank or reservoir that is filled using an external air source — usually a carbon-fiber tank filled at a dive or paintball shop or filled directly with a compressor. In the past, compressors were very expensive, however compressors designed to fill guns directly up to 4,500 psi are now available at a much lower price point.
For these very powerful rifles, a fill pressure over 4,000 psi is commonly used, and depending on the rifle each fill will allow three to six shots before the on-board air storage must be refilled. Most big-bore airguns experience a reduction in pressure with each subsequent shot on a fill, resulting in a reduction in power and drop in point of impact over the shot string. Guns can be adjusted to minimize this effect or may use a device called a regulator to operate at a standardized pressure for each shot, which improves consistency.
Big-bore airguns are available in many calibers, but arguably the most popular are .308, .357, .40, .457 and .50. Over the past couple years, one of the manufacturers I’ll present, has been using larger calibers such as .58 and .72. My favorite caliber has been the .457, but when discussing the most powerful guns the caliber will invariably be .50-caliber or larger. If you look at a particular model of rifle available in both .457- and .50-caliber, the latter will typically be 100 fpe more powerful.
Meet the Powerhouses
So, what types of power outputs do these guns generate? For many years, hitting 600 fpe was the holy grail that gunmakers strived for. In short order, the AirForce Texan .457, AoA .457 and Hatsan Piledriver .457 hit this mark or crept slightly past it. To put this in context, on my first hunt in South Africa I used the Quackenbush .50-caliber, generating 450 fpe to drop a kudu at 75 yards. A gun putting out 600 fpe was a significant step up in power output! After reaching the 600 fpe mark, manufacturers started implementing higher fill pressures, larger calibers, along with improved valve technology and materials, to push well past this power threshold.
The three rifles I’ve selected as the most powerful production guns are based on both published specifications and my own experience with them. To this end, when a rifle is available in multiple calibers, I have opted for the one that produces the highest energy levels for that model. They are, the Hatsan Piledriver .50-caliber, the AirForce Texan .50-caliber and the AEA Zeus .72-caliber. In addition to extensive range work, I have taken deer and will hogs with all of them.


















