Blue, the lower serial numbered 03's (under 800,000) were a concern for many years, as a few dozen of them blew up due to brittle actions. At this point I suspect it's probably not a concern, but I would not push the loads very hard:

http://thecmp.org/cmp_sales/rifle_sales/m1903-m1903a3/

not an 03 expert but sounds like yours was rebarreled


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