So, watch that "Unlike Most People" thingie...
Toting an M16A1 on a public bus is a bit different.
You get used to the weight to the point you don't notice it any more - but length, now that's a problem.
In the Army, some people call it the "sorry gun", because of the manner you need to express yourself while carrying it on buses - "Oh, I'm sorry, I bumped into you with the stock, I'm sorry, ma'am, I didn't
mean to jab the barrel into your forehead..."
That, and the foregrips tending to fall off on old ones.