I did say it was a stupid question, because what may work for one may not work for another. "What ever works for ya baby" rules here.
As a disclaimer, it wasn't my question!
For most soldiers, and LEO's, we don't have a choice. We do with what we have. And what it will comes down to, they all will work.
And what is defined as "combat". It could be that 12 second exchange of gunfire, most likely even less b/c 12 seconds is a looooong time. Or a long conflict, and no I don't mean Iraq. I had Stalingrad in mind. Where resupply is a luxury and rotating from a foward position to...... another foward position. It was all foward for the Russians.
Then there is the "bean counter" factor. Inexpensive v. expensive is relative to quality and neccesity is relative to whatever you can get your meat beaters on at the time.
I love how simple, cheap to make to the point of being disposable but yet effective the AK's are. Iif I were a dictator of a two bit nation (my childhood dream) I'd equip mah boys with AKs. Heck, I'd do whatever I could to make em in-house. That and wear a red shirt.
Now give me an elite squad of airsofters with an unlimited budget and the sky'd the limit!!
About the DI thing in the AR. The only issue I have with that is yes, it's a pain in the ass when it comes to cleaning an AR. I could see if you don't get good ammo that it may present a problem but mostly our Army is well supplied. It will not be the issue for most of us in a SHTF Stalingradlike enviroment.
Here is my worst case experience regarding carbon build up in an AR type weapon:
As my stations FA instructor (about 300 Agents) we have pool M4's Agents use at the range to qualify every quarter. These guns each put at the minimum 50 rounds a day and 5 days a week minimum, seldom to never get clean. They don't get exposed to duty carry so it's strictly a carbon making machine.
I also know that these M4 have not been thoroughly cleaned in over 2 years, the last time I cleaned the BCG. In the AR carbon ends up in two places. One is onside the bolt carrier and end of bolt. I have one of those Brownell's carbon scraping tool and it works pretty darn well. They do build up quite a bit of carbon in there. The other place is the gas tube well in the upper receiver. That's another story!!
I had to clean 10 pool weapons in a crevise that has never seen day light. That little area was so jammed packed with carbon I thought I'd never see the end of it. Even trying to pull the gas tube out was futile as they were practically fused with carbon in place. Only a cotter pin removal pick, my dental tool until I broke it, and much feneagaling was I able to remove most of that carbon. And that stuff was tough. The entire BCG I just dumped into the ultra sonic cleaner, ran them twice, to include soaking the entire bolts in CLP and that scraper. I'd have to admit that those M4's still ran fine in that condition. In my entire life, none of my AR's or issued M16's and M4 ever got that bad.
About a "combat" tested whatever:
Now I'd also add when things get tested for the military it is usually done at a lab first, then it goes to field testing which it is exposed to less of a controlled enviroment. But neither a lab or field testing will replicate a combat enviroment. A lab will only expose the 'whatever' being tested to things the 'whatever' may encounter in the field. In the field trials, the 'whatever' gets carried by troops and put through the paces in a simulated and similar conditions to that of combat. These usually take place on military installations, safety takes a front seat here, EPA has a say, yadda yadda....
Now in combat all that goes out the window in the first 2 seconds. I will elaborate more on my piss and shit bath;
I was not directly under fire at that time or pretty much the whole ordeal that day. I was trying to get into a position to spot the sniper taking shots at us or support my squad in doing the same and hoping that I would and could take care of the problem. When bullets start flying and with proper training and experience you would naturally look for cover and concealment and use the same when maneuvering to a bad guy.
This played out right next to a popular market area south of Mogadishu in July 1993 and in support of Pakistani soldiers trying to arrest some local shit bags involved in the ambush that killed 24 Pakistani's. Now I must tell you, a Somalian market is NOT like a mall or super market in the US. They include pens for goats, chickens, sheep, cows, donkeys, etc. Now I was near these pens. I saw a low spot surrounded by brush that I THOUGHT was ideal to move well covered and concealed.
Now where do you think animal (I'm sure human too) urine and feces ends up after it rains, also when they clean the pens out. Well there was a good reason as to why this low spot was surrounded by lush green bushes. As I busted through the outer brush and as soon as my foot made solid contact into the wet outer rim, it sank in about a foot into this "mud". My weight, and the additional 30 to 40 pounds of kevlar, ammo, and such, carried me forward, with my M16 slung in a makeshift tactical sling similar to a 3 point. NOTE TO SELF: third world shitholes are called shitholes for a reason AND they do not have infrastructures, such as sewers, as we are accustomed to here in the US. And be leery of lush green vegetation in desert countries.
And that boys and girl is how to take a shit bath and having an M16 go into it FIRST because I do hold it with both hands while I run and I did put those out in front of me. The 2 or 3 attempts to get up right after that just made things worse. I did get out and thank god that crap was only about a foot or so deep. My barrel stayed out of it but it immediately rendered my rear sight useless for a while (take note boys and girl, we didn't have Aimpoints then. Do we see an issue with oprics here?). It wasn't as if I wanted to go almost face first into goat, sheep, donkey, whatever piss and shit.
Now lets fast forward a bit. We made it back to the airfield, my fellow troops "helped" hose me off with 'fresh' water. Of course they only did it for their own personnal amusement, why else would they be there? I did get my M16A2, and uniform clean. I also unloaded all my mags and cleaned them as well as I could. Same went for my LBV and kevlar vest. One thing I could say about Somalia, Saudi, and Iraq, was when it was hot, things dry pretty quick. I didn't get to one mag AND you can't wash out codura or nylon as well the first few times.
One thing I did notice shortly is how ammonia laden urine will corrode things, specially turning brass turquoise in color. When we got rained on some of that remaining dried on mud in my gear would reconstitute and go back into my mags. I also noticed how that turquiose color stuff dripped out of my mags for months and having to dissasemble mags and finding the mag springs very corroded. I did toss them out. I laso saw how ammonia laden urine react to aluminum mags and they will corrode too at the seam and weld. You could see the turquoise colored drips from my mag pouches.
So you see, would a lab technitian would ever wonder how the 'whatever' would handle goat piss and shit? And would a soldier evaluating a 'whatever' think about diving into a goat piss and shit? I would have never thought of it either. And you don't see the gun mag rags peeing on their guns "just to see" how they handle it. And of course I don't go around doing it either.
The same goes for a freshly made B52 bomb crater with mud and water in the bottom laden with explosive chemical compounds and corroding steel. The water was black!! I didn't get into one but I knew one SAW gunner that did. And if you think that was my only experience of falling into a raw sewage enviroment with a gun, you'd be mistaken. But I'll save that for another day.
But it does go to show that in combat you will be exposed to things that no one would or could have thought of.
Tzoid, pee on your XCR and get back to us with that report.