I thought I had lost my file on AMU match ammo, BUT I found it.
This article was in Handloader magazine March-April 1975 by Don Dawkins (I start with the first paragragh)
Big Bore competition takes a lot of ammunition – good ammunition. Since the government manufacture of National Match Ammunition has been stopped, military teams especially, have had to look elsewhere for the quality ammunition they need for practice and competition. Until recently, Remington had been doing the loading for the Army Advanced Markmanship Unit, but they quit and the AMU had to look for a new source. That new source is Jensen’s Custom Ammunition in Tucson, Arizona. (end quote)
I had forgot about this article, it goes on to say that the first contract was 98,000 rounds of 7.62mm Match. It also states that AMU specified that the load be XX grains of IMR-3031 with a 168-grain Sierra International Hollow Point using Winchester-Western cases, and Remington 9 1/2 primers. That finished ammunition produce average 300 meter 10 shot groups from several test barrels averaging no larger than 2.5 inches. The AMU preferred the Remington primer in that combination for the ammo produced 2.1-inch average groups at 300 meters. Two overall lengths were required: 2.8 inches for use in the National Match M14 and 2.9 inches for slowfire where loading can be used. (the article does not state how these two cartridge lengths where marked or labeled on boxes).
OK it goes on to state that the first 20,000 rounds were loaded that way. Jensen then sent the AMU a batch of test loads in factory-primed Federal cases: AMU reported that these gave accuracy equal to or slightly better than the Remington-primed Winchester cases. So the contract was completed with the Federal-primed brass.
About once or twice a year I shoot 500 yard F-class with Bob Jensen at the Phoenix Rod and Gun Club, the next time I see him I will ask him how many contracts, 98,000 or other wise did his company do.