I am looking forward to see if any thing is found on the use of non-national match Springfield rifles that were set up with the Unertl scope . Back in the 1960's I spoke to a retired Marine Corps armorer who worked in the Philadelphia Navy yard where they built the snipers. He said that they ran out of National Match 1903 Springfields and ended up using low number rifles . The order was given to install new barrels and proof them with a 70,000 lb. proof round and fire 10 standard rounds . Than use a 5 pound brass maul to beat the receiver ring fire a second 70.000 proof round and 10 standard rounds ,If the showed no damage it was good to go !!!