just how many times do you "think" you can MISS and still win, against guys like US?

There is a higher % of gun people here than any where in the world, by a factor of 10, at least. It won't be ignorant rice farmers or goatherds that you'll be facing, a month or 2 after shtf. The ignorant will all be dead already. Not one person in 1000 is properly prepped, so nearly everyone will have to be come a looter, and sooner, rather than later, too.
how many guys do you think will MISS YOU while you are hitting them? It took Audey Murphy 2 years of the toughest fighting ever seen to hit 241 men. You aint Audie, and you wont have bombs, artillery, or lots of buddies helping you, either. Audie was the first to admit that he survived by pure luck, many, many times.
If you are HITTING, there will be plenty of guns and ammo to pick up, lying beside dead men. You will HAVE to carry at least 30 lbs of other gear, at all times, on top of your guns and ammo, you know. There will be no choppers coming to help or extract you, minor injuries will probably result in your death, too, due to lack of modern med care. If you drop your "non-combat" gear, in a fight, you'll probably never get it back, and there will be "re-issue" via some Supply Sergeant. So you'd better rethink this bs about hundreds and hundreds of rds being "needed". Above ground buildings will all be searched, many times over.
At night, you certainly won't be hitting cover users beyond 100 yds, even with a laser target designator, or head on prone men past 200 yds, or those who are dodging. Very few men can do this in good light, with good ear protection and in good light. Men are going to over that 200 yds in less than one minute, even if gonig prone, using cover, dodging, etc, and you are not going to be getting more than maybe 20 hits in that time, no matter who you are. ONly fools will be attacking any "forts" or buildings in daylight. the minute you "open up", they will scatter-flee, and be back after dark. If you lack lots of rechargable batteries and a solar charger, your NVD'S won't last very long.
If you have no sound suppressor on your rifle, your night vision will be gone with the first shot that you fire, most likely. Have you got tritium sight inserts on your rifle? If not, you won't be hitting dodging men beyond 25 yds, at night.

So you will be "overrun" or picked off, in pretty short order, actually. The tactic of choice is not to be out in daylight, if shtf. Then very little shooting will be required, and if most of it is not suppressed, subsonic shooting, from ambush, you will make it only by pure luck, the way 1 insect in 10,000 survives ANY sort of poison spray you put on them (of one type, anyway).