The way I see it, the Boresnake is designed to drop down thru an Unobstructed barrel until the small weighted end comes out the other side, then you pull it thru.
Now if you have mud/dirt Impacted in the barrel or a round stuck, etc. it seems like it would be useless. And as far as a "Hostile situation" you could run 2K rd thru your gun in a 3 day period and not sweat you bore at all. That's the least critical part to clean anyhow. You should be more concerend with a clean chamber and a clean bolt and carrier...
with a chrome lined bore (or even without one) the barrel can run a lot of rounds down range without effecting your performance or accuracy. never saw a need for a boresnake. Always thought it was a marketing Hype thing as I see it in a very limited use role for what it does. JMHO..