I've seen 10 million rounds of 50 BMG all in one room .
A unamed party has many rooms with with many times that in smaller cartridges occupying similar spaces .
It is like wine in some regards . Some of it is from 1st to 3rd lots of current favorites , some of it is MASH story era in the JMB family and the other 2/3 is Carlo Rossi and Ripple from whatever was left over in Bakersfield after Napa got done with the hand selection .
Of course that was a number of years ago , it's probably been 25 years since bulk packs of LC 42 belted 50 BMG was suplussed out in rail cars pushing max gross weights ........
Lots of commercial ammo in popular cartridges has crimped primers now . Old standards have mixed primer pockets even from the same brands . I suspect bean counters saying "but we will save 2 man hours on the cartridge change over if we don't have to change out the feed tubes" .
Remington went to sale with some 9-10 digit back order of ammunition orders pending , 2 yr ago . They didn't run it , it hasn't been run by a transfer team , and the new owners can't run it because their ownership is under review for anti-trust law legality of transfer . Current wholesale values , tilted toward the mean not the average puts that at about 200,000,000 boxes of ammo in 20,25, and 50 count boxes . Ya know just round numbers at $5 a box assuming 264 WM , 45-70 , and 45 Colts are really at $14-20 per Wholesale and RF ammo balances that out in $2.50 50 counts . That's just a hiccup in supply going into 2020 , that void of lost production in just cases not even loaded ammo has an impact even if it is just a piddly 12-15% of the gross market . Demand goes up 40% against market that's only at 80% of recovery from the last train wreck and and take away 10% of production and there's 95-97% demand draw against production every day .......add the rush and it becomes a 125-150% draw and any stocking or warehousing buffers disappear in a hurry .
Pending decisions by the people this summer may help the situation some but it could just as easily make bootleggers running the border from Canada a real thing again only for powder and primers instead whiskey .