Hi Eric,
No, what you've described is textbook Lake City packaging of their M118 Match ammo of that vintage. Went through tons of this stuff while I was in the army, as well as converting a great deal of it to "Mexcian Match." This is the factory ammo that has had the 173 FMJBT pulled and replaced by a 168 SMK, with no other changes. NATO specs for this stuff allowed OALs out to about 2.850", so that's nothing unusual. At a 2.014" case length, that's at the high end (2.015" maximum) but still within the window. The asphalt sealant is a typical feature in military ammo, intended to waterproof it and provide better long-term viability of the ammo. Believe it or not, it actually doesn't hurt accuracy as you'd think it would. Breaking the seal immediately before firing seems to help a bit, but nothing really significant. I think as much as anything, we did it because the old timers told us that's always the way they'd done it. Anyway, you might try changing the bullet and making Mexican Match, as I'd described. We used to have details assigined to do this in our loading rooms; one press set up with a collet type bullet puller, and the one next to it set up with a seating die. The first guy would pull the bullet and hand the still charged case off to the guy beside him, who would then seat a 168 right back on the same powder charge. Significant accuracy improvement, right then and there with no other work. Lake City eventually adopted this practice and began loading the 168s, dubbing the finished product as their M852 National Match ammunition. The M118 became M118 Special Ball, and was from that point on packaged in a plain brown box with a very simple white label pasted on describing the ammo. It remained in the inventory for many years afterwards as the Combat round for snipers, until it was finally supersceeded by the current M118LR, which replaced both the M852 and the M118 Special Ball. Yours, in the fancy NM "White Box" predates all that and gets you a few "cool points" as well.
The powder should be IMR4895, as this was the standard load used during the years that Remington ran the Lake City operation. They switched to a ball powder (WC-750) when Olin won the contract, and then to RL-15 when ATK got the bid in later years. Point being, there's a number of different powders that they've used over the years, depending on who was running the operation at the time. For this period, however, it's almost certainly IMR4895. Most of this stuff shot right at MOA or maybe a bit better, which was no mean feat with a FMJ style bullet. If you try making Mexican Match, as I've described, that should tighten that up a bit. Seated down to 2.800", it may well also solve the chambering issue, if it is an interference problem with the ogive of the FMJs. Might be worth a try if you want to use the ammo and don't mind the work, but I'm sure you can also find a buyer for it if you choose to go that route. Shame the case is already opened and unsealed, as that would have commanded a premium.
