Derp.

At the last Indy 1500 fun show, the ammo situation was pretty grim. Those dealers who had 5.56 in bulk quantities had it priced in accordance with its scarcity and desirability (those that didn't found themselves quickly cleaned out and unable to restock.)

I've got a fair amount of 5.56 ammo on hand, enough for a couple classes and a few range trips, if it comes to that, but there was one thing I noticed at the show that had me slapping my forehead and feeling like a maroon.

See, while almost all service rifle calibers, even 7.62x54R, were effected to one extent or another by the hysteria, spam cans of Russian surplus 5.45x39mm were still ubiquitous and extremely reasonably-priced, especially by contemporary standards.

If one had a switch-barrel AR upper from MGI Military, like the one pictured below, one could just swap in one's 5.45 barrel and bolt and be assured of a supply of cheap and readily-available centerfire ammo...

...and it uses standard AR barrels!

...assuming that one was all smart and stuff and had actually procured a 5.45 barrel and bolt ahead of time, because asking around at the show only resulted in vendors looking at me like I was speaking Armenian.

Incidentally, this should have occurred to me much earlier. During the last great ammo panic, smart people were using factory 5.45 ARs from Smith & Wesson to keep their hand in when high-volume shooting with factory 5.56 would have been nearly prohibitive.
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