PGWTW338,
The primers would be my concern here, and it's a relatively minor one; they're likely corrosive. In doing a quick check, I show that LC changed over to non-corrosive priming in their 30-06 ball ammo in 1951, and that any ammo headstamped '51 or earlier should be treated as corrosive. Unfortunately, I don't have any info on 50 BMG ammo, or when the switch was made for this. Not a big deal, really, but means that the bore will need to be cleaned with soap and water after firing. Regular solvents won't mitigate the effects of corrosive priming, as the potassium chloride (essentially, salt) is unaffected by solvents. Water, however, will dissolve it completely, and it can then be removed. Follow up with regular solvents, and oil the bore when done, and you're in business.
Aside from that, LC has a long history of making pretty decent brass. Your 50 BMG cases are likely no exception to that rule.
