I still have a box of 3 1/2" Bismuth from early 2000's. I have a gore tex rain coat that I wore as a kid. Now my wife wears it. A Remington ammo wallet that I started hunting with. I still have my first 12 gauge. Benelli Nova and my first 22lr Winchester lr also my first rifle Ruger M77 MK2 3006...
I put a bad shot on a doe with a rage hypodermic. Hit her in the spine. The rage severed her spine and dropped her instantly. The rage was in perfect condition. I was in shock how well it worked and held together.
If you have any more of this ammo in the same lot number you could weigh each round if you have a scale and also take an overall measurement. At least give you peace of mind that the rest are at spec. Definitely reach out to Hornady.
When you say residual lube. Like solvent from the bore? What kind of lube are you using and how? This does seem odd that it just happened today. Could be a bad batch of ammo. Are the lot numbers the same as the previous boxes?
I shot mine at 200 the other day with bipod and rear bag and the amount of flex just from my cheek weld was irritating. I have to get one of these stocks.