Thanks for all the replies. I received the ammo today and it looks very nice and is nicely packaged. To answer some of your questions:
1. Primers are large pistol and not crimped.
2. According to Revolverguy's post above, he chrono'ed this ammo at 862 ft/sec.
3. Headstamp is WMA 18. WMA is Winchester's plant in Mississippi; it stands for Winchester Military Ammunition, but they produce both military and commercial ammunition. I assume the 18 means 2018, so it's the freshest ammo I've got (unless it's WW I surplus from 1918!).
4. I don't know whether this ammo is more or less accurate than my reloads, which are mostly 185-200 grain bullets at about 750 ft/sec, but I'll certainly try to determine that.
5. Thanks for the invitation to the Flatlands, but I live east of Cleveland more than 200 miles away, so I'll have to pass.
6. I do carry hardball sometimes in my 1911's. Used to use Hornady, but they stopped making .45 ACP hardball, now using Federal which is a bit hotter. I'll consider using this ammo for carry after shooting a couple of hundred rounds.