I would like to know how much my ammo weighs per 100 or 1k or whatever.  If you already know you could save me alot of time.

.22lr bulk pack 36 grain

9mm 115 grain fmj

5.56 m193

12 gauge 00 buck, 2 3/4 9 pellet

12 gauge winchester bulk packs 7/12 or #8 birdshot

.45 acp 230 grain ball

I am sure there are charts or "guesstimates" of what they would be, BUT: please remember that you have variances in the tolerance of a lot of the brass cases  at issue here, such that a 1,000 pieces will vary because of the variance in the actual weight of the brass. Not so much the powder charges or the bullets, but the cases will vary within some range. Can you do "ballpark" estimates?" Sure.

I have used a 3 lb coffee can to measure fully loaded rounds or empty brass or bullets, but it just gives me a very rough estimate of "X" number of pounds or "X" number of pieces. Kinda like when you go to those "Mr. Bulky" food stores where you buy flour, sugar, coffee, beans by the scoop or pound.

yeah this doesnt need to be too scientific.  just for my own benefit.

bathroom scale is your friend........

Do you really have that much that you can't take the time to count it?  Is this just something to do for fun?  

I would suggest that you load up ammo cans and tag them with contents and qty so you have a proper inventory of your stuff.  You don't have to do them all at once, just a couple of cans a week will get you there.

840 rds M855 on stripper clips in LC can = 22lbs

Maybe this will help:
weighed on a digital shipping scale

50rds older Federal 230grn
45acp ball in paper box w/styrofoam insert 2.6 lbs

100rds PRVI 55 grain M193 in plastic Baggie   2.6 lbs

10rds Remmington Peters 12 Ga 2 3/4 00Buck 12 nickle plated pellets per round in paper box  1.4lbs w/4 drams of powder high brass

550Rds Federal Value Pack .22 Long Rifle 36 grain Copper Plated hollow point 4LBS.

Too lazy to look for the bird shot, and the 9mm I've got right now is 124 grain sorry!!

ETA:
For years not only did I keep a running inventory, but I kept a running inventory by weight. What a pain in the ass!
I had to, I'd moved 4 times in two years, and my ammo stash didn't get any lower while I moved. I was stacking it real REAL DEEP in those days. I had to be careful I didn't overload any trucks. If I ever move again...just take me out back

990 rds m855 was 27.2 lbs according to UPS

My 5.56 reloads average 177 grains each.  So 1000 of them would be 177000 grains which is 25 lbs 5 oz.  These are with 55 gr projectiles.

Just store them in mags

Be easier to count mags than all the rounds

One round of Wolf Match target 22LR averages 51.6 grains. i hope I helped.