In Bushmaster’s product line-up, the M17-S bullpup was always the odd one. It shared a few components with the AR-15 rifle, but remained more of a low-volume curiosity for its entire 13-year product run. This rifle has its origins in the Leader T2 rifle mentioned last week. In 1986 the Australian Army invited bids to replace the L1A1 rifle. Charles St.George submitted an improved select-fire version of the Leader T2 designated the M18. The M18 used a short stroke piston and a gas regulator, with the non-reciprocating charging handle, bolt carrier and two action rods of the T2. The plunger ejector was changed to a fixed ejector like the Stoner 63. A folding stock was added. Beta light sighting system was to be standard. The Australian army eventually adopted the Steyr AUG instead and produced it under a license as F88.
Charles re-designed the trigger mechanism and converted the M18 into a bullpup rifle named the ART30. Once fully developed it was licensed to Bushmaster as M17-S. Probably to make use of more common parts, the U.S. version used AR-15 type plunger and a further altered trigger mechanism. A heavier extruded receiver added noticeable extra weight. The lower receiver was also altered in a way which made stripping and removal of the bolt carrier assembly more difficult. Rudimentary emergency open sights were built into the “carry handle”, but it was expected that an optical sight would be used. At the time, the reliance on optics for a defensive rifle was considered a flaw by most.
Partly as the result of those changes, the rifle came out somewhat heavy, with a spongy trigger and tended to retain heat. The heavy weight was mitigated by the excellent balance and very low felt recoil. With right-hand only ejection, it was also an awkward fit for left-handed users. Since bullpups were new, few training materials existed and most shooters viewed the manual of arms as awkward. One major plus of the M17-S was its use of the standard STANAG magazine. During the ban years (1994-2004), AUG magazines were extremely expensive, while AR-15 magazines remained at least somewhat affordable. The rifle itself cost about two-thirds of an AR-15 because the design allowed cost-effective manufacturing.
Recently, I test-fired an M17-S modified by K&M Aerospace. The modification started with ventilating the receiver to reduce weight by half a pound and to improve air flow. Combined with the already thick barrel, the ventilation greatly improved the sustained fire capability. Use of a vertical foregrip further insulated the support hand from the barrel heat. The “carry handle” was removed and replaced with two rails, permitting the use of standard AR-15 optics and other accessories. The longer rail also provided useful separation between the front and rear backup sights. Because of the central balance of the original rifle, addition of accessories didn’t make the gun too front heavy. Fired with GRSC 1-4x scope set to 4x, this modified rifle shot at 2MOA from prone with plain American Eagle 55gr ball. Surprisingly, the mechanical noise of the operating parts was not noticeable at all.
The major issues with the M17-S —weight, trigger quality and awkward take-down—have been addressed in the next rifle designed by St.George. I will cover it in the next chapter of this tale.