In the late 70s and early 80s, the ammunition industry was going crazy trying to match strides with the arms industry in the development of semi-automatic pistols. While gunmakers of the time were building the best revolvers in history, it was clear the service handgun of the future would be the semi-automatic pistol.

At the time, there were new guns, new styles of guns and new calibers galore. There was also a perceived need for ammo that would do things never before asked of the humble pistol bullet. An excellent example of this trend was the mysterious GAS bullet (sometimes known as the BAT bullet) made by GECO of Germany and Austria.

The GAS bullet was designed with several interesting parameters. Intended for the troopers of Germany's CSG-9, the GAS slug was originally intended for use in 9 mm pistols and submachine guns, meaning it had to feed with total reliability. For that, an FMJ or ball profile was in order.

Since these elite troops were often involved in pursuits of terrorists on Germany's high-speed highways, they wanted a bullet that would instantly deflate a tire. They decided on an all-copper bullet with a huge hollow point that led down to a hole that ran clear through to the base of the bullet. It was essentially tubular, but the front cavity was filled with a plastic plug shaped a bit like an opened umbrella.

The rounded contour insured good feeding and the bullet came out of the gun's muzzle with the “umbrella” in place. Pressure popped it loose and it fell away harmlessly, leaving a light (86 grain) bullet with a huge, razor-edged hollow point cavity whizzing along at 1400 fps.

When it hit a tire, it cut a perfect 9 mm hole taking a plug of rubber with it. The tire went flat in an instant. Although the GAS bullet was never intended for antipersonnel use, it was pretty good at that, cutting bleeding holes and absolutely splintering bone in the process. The GAS bullet is an interesting footnote in ammunition history.