The .577 T-Rex is more than capable of stopping a rhinocerous.
Big bullets and lots of propellant translates into substantial stopping power, and that is the raison d’etre for the .577 T-Rex. This rifle fires one of the biggest and most powerful rounds around, and is easily capable of stopping some of the biggest animals on the planet. It isn’t hard to imagine the rifle stopping a truck, if it came down to it. Even so, the power of the .577 T-Rex does come with certain drawbacks.
The .577 Tyrannosaurus Rex (or .577 T-Rex) is a gun made by A-Square, a small firearms manufacturing company that specializes in big-game rifles, or “elephant guns.” Basically, it fires a big bullet at high velocity for the express purpose of stopping the largest animals on the planet. The .577 T-Rex is a bolt-action rifle, meaning the bolt must be worked between each firing to chamber a fresh round. It weighs 13.6 pounds.
It is often believed that T-Rex is the most powerful rifle in the world, because the .577 round fired by the T-Rex is bigger than the .50 round used by the U.S. military’s heavy machine guns and its heaviest sniper rifle. In fact, rifles firing rounds as big or bigger have been around since the 1930s. The Soviets fielded an anti-tank rifle, the PTRS-41, that fired a 14.5 mm round that was slightly smaller. However, some versions of the ammunition packed more power. The 14.5 mm round continues to be used in Russian high-powered sniper rifles today. Even bigger were the anti-tank rifles of the 1930s and 1940s that fired 20 mm/.79 caliber rounds, and 20 mm sniper rifles are also made today. However, in terms of hunting arms, the .577 T-Rex is the biggest and most powerful commercially made gun available.
A .577 round produces between 10,000 and 11,000 foot pounds of energy, a truly staggering wallop. That is seven times more energy than the 5.56 mm round fired by the U.S. military’s standard rifle, the M-16. A shot from a .577 T-Rex rifle is very capable of stopping a rhinoceros or an elephant in its tracks.
While the bullet from the .577 T-Rex rifle is extremely powerful, it is also very inaccurate. The gun was meant to be used almost as a last resort against very large, charging animals at short or short-to-medium range. Accuratereloading.com did a test with a selection of .577 rounds, and their shots fell into an area eight inches across. Other big-caliber elephant guns placed their shots into a three-inch wide area or an even smaller spacing.
The gun also has a wicked kick, as one might expect from a such a light rifle firing such a huge round. By contrast, the NTW 14.5 mm sniper rifle weighs 35 lbs., and that extra weight translates into less kick.
The .577 T-Rex is a just-in-case gun. It is not the kind of rifle one carries into the Kalahari or the Yukon to hunt big game, because the gun is too inaccurate for use at range. Instead, this is a gun carried as a hedge against being surprised by an aggressive big game animal at close range. Given that the gun is essentially a backup weapon, that means in practice a hunter would carry their actual hunting arm and the heavy .577 T-Rex, as well. While it is easy to see a safari or group hunting expedition bringing along one .577 T-Rex, few individual hunters would have much use for one.