I actually went with a much simpler method..... more to follow when I can dig out a sample. But in short, I did not vacuum pack due to info I had at the time. I have a largish case...or so... of loaded P-mags ready to go. When I moved last fall, everything was inspected and found in perfect order, with no issues. Probably should do a test fire just for giggles.
The ww2 reproduction ammo boxes came in and I used most of them and they work great. Pack real nice in a 50 cal ammo can.
Well I needed some more ammo boxes. I mined thousands of 223/5.56 cases from the local shooting pit. Lots of cleaning, sizing, depriming, more cleaning, trimming, deburring, more cleaning, sorting then loading. You can find wolf and tula 223 boxes dirt cheap since there's no reason to keep them, cause the cases are steel.
I get free empty ammo boxes from the nearby indoor shooting range, always get some 9mm, a few 223 and maybe something else if I'm lucky like a 45acp or 38spl.
I’ll keep factory boxes after shooting the ammo. Or scrounge an occasional few at a range. Everything goes in surplus 30 or 50 caliber cans. Boxed or loose. I basically only reload 9mm for pistol and PCC. Have components and dies for my other cals but haven’t done much with those. Shotgun is my thing now as I got roped into trap shooting. We even drip our own shot when we can.
you can improve the gasket in the older metal boxes - there's rolls of bulk "O ring" thats the same size as the original - hook the old out - apply a little Vaseline - new gasket pops right in ;;;;;;;;;;;
ammo isn't anything I'd bother vac packing - the vacuum only holds for 8 months at the max >>> get some 1/2 gallon mylar bags - 500cc 02 absorbers - heat seal and you're good for a lifetime - void of 02 and waterproof ;;;;;;;;; for added insurance - include a small desiccant pack for any moisture ;;;;;;;;; for a bulk load use a 5 gallon bucket with locking lid - 5/6gal mylar bag - 3-3500 cc of 02 absorbers ;;;;;;;;