In the late 1980s there was a move to replace the Colt M-16A-2 with a replacement rifle, so trials began with 4 competitors: Colt, Steyr (Austrian), HK (German), and AAI. Colt produced an ACR (Advanced Combat Rifle) that was little more than a modified M-16A-2 with cosmetic improvements, ambidexterous fire selector, and the handle becoming a rail mount for a scope. There was a new muzzle-brake/compensator and a new 5.56x46mm Winchester Duplex round that contained 2 bullets- 1 to penetrate and the other as follow-up in case of sighting error. They did not follow one behind the other-the second was randomly close! Anyway, Steyr had a flechette (steel dart) firing bullpup based on their AUG while HK had a modified G-11 caseless weapon simplified for the US Army with a different exposed barrel and only a single railing for the 50 rd mag (cal 4.77mm) that fed a radical cylinder breech in bullpup style. In 3-rd burst it could fire at 2200 rpm at nearly 4000 fps! Normal auto fire was a more reasonable 600 rpm. And lastly was the other American competitor from AAI Corporation which also fired a 5.56mm flechette using an advanced gas system and using a "quick release" lever for all scopes (just like a bicycle quick release of front wheel). Round would be fired at 500 rpm at 4600 fps! The only disadvantage with the gas system was that normal NATO 5.56mm ammo could not be used at all because the gun would jam quickly. So, the mags were custom to fit only the AAI rifle and would not accept normal 5.56 ammo loading. So, it was totally reliant on its own 5.56x45mm flechette ammo. No other NATO forces could use it with their 5.56mm ammo. Anyway, as the competition moved forward it looked like Colt would lose to any of the other 3 and this would be a massive blow to their manufacturing of military arms, so they were bailed out a second time. The US Army kept the M-16A-2 until the M-4 arrived. In 2006 Colt was bailed out a third time when it looked like the US was going to go with the joint US-German XM-8 (a US-tailored custom German HK G-36) over the Colt M-4. At present Colt still fails to provide a better infantry rifle and faces the HK 416 and 417 as well as the FN SCAR and Remington ACR. My parody concerns only the AAI ACR.

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