There was a 3-gun sidematch this past weekend after the regular IDPA match up in Ripon, Wisconsin.  Out of 21 people, 19 used a variety of AR’s.  The first stage started with the shooter engaging multiple targets with his AR from the left side of cover, this meant a “mirror image” hold.  From there, they’d then transition to handgun and engage some more targets while running to another spot.  There they’d engage another array with their rifle, this time coming out from cover on the right.

What was weird was the amount of rifle problems people had shooting from their weak shoulder.

You could tell that for a majority of the shooters, this was the first time they’d ever pulled the trigger of a rifle using their left hand.  Still - I was puzzled at the number of malfunctions that occurred when people weren’t using their familiar “right-handed” hold.

I was more than a little surprised to see this happen in a gas-operated weapon.  It’s like the rifles were prone to short stroking unless they were snug up against the shoulder.  I’m pretty sure this was limited to 16” AR’s too – the 20” critters were very reliable (but that’s a whole ‘nother topic!).

Has anyone ever seen anything like this before?  Is it possible to “limp shoulder” an AR?

To be honest I dont know.I practice with my left evry time I shoot and have never had any malfunctions.I know shooting a .45 limp wristed can induce malfunctions but I dont know with the AR.Next time I go Ill have to try and see like rotating it right to left while firing to see if it happens.

That's strange.  The only problems I have seen with left-handed AR shooting is the fired brass bounces off of the support (right) arm and back into the receiver, causing a malfunction.  I had this happen to me at first until I figured it out and changed my support arm position.  Actually, it can look like short stroking because there is an empty case in the rifle.  The difference is that the rifle is also in the process of stripping a new round in this type of malfunction whereas in a short stroking situation it usually is not (though it can be).  Do you think that this is what was happening?  I thought mine was short stroking when it happened to me, but it was just brass bouncing back in the ejection port.    

I am left handed, and never have a problem. My brass ejects at 90 degrees, does not hit me or my brass deflector.

Surely coincidental.

I'm ambidexterous with a rifle (although I prefer left-handed) but right-handed with everything else.

Never heard, seen, or had this problem that you mention.

Yeah, it is, contrary to what I've always thought about gas operated weapons.

Had an officer come up to me at an LE conference some years back, she was having short strokes with her duty (BFI 16") rifle. I watched her test fire it on the line. That night I pulled the rifle apart in my hotel room but couldn't find anthing wrong with it. She got to see parts of her rifle she never wanted to. [}:D]

The next day we went back out to the range and I fired 2 boxes of Black Hills ammo (her agency's load) through the rifle without a hitch. I told her it couldn't be fixed bc all I had done was take it apart (completely) and check it. As she was part of the synergy I put her back into play.

She loaded up more mags from the same case of ammo and took it for a spin. 1st round down range ended in a shortstroke. SPORTS, fire, shortstroke, and so on for 10 or so rounds. I took the rifle and fired off the rest of the mag without a problem as fast I could pull the trigger.

We reloaded mags and proceeded to each fire then hand it to the other. Every time (mostly) that she fired the rifle it would short stroke. I rechecked the gas system for anything that may have come loose and then dropped my test fire carrier into her rifle. Ran like a charm. A new carrier from the parts box put her right and last I heard it was still running.

The 6,000 round endurance test outlined in the M16 milspec calls for portions of each phase to be fired with the rifle "unrestrained". No doubt for this very reason.