I personally shoot my low number 03 and almost all of it has been military surplus M2 ball. I think that if mine was going to blow it would have done so before a replacement bolt and barrel at the ends of WWI and WWII.
however this is always a risk of them going Kaboom and CMP wont allow low serial 1903s to compete in their matches. if you are willing to accept the consequences of shooting should it fail then go for it.
KraigWY will be along shortly to add his .02
ignore my complete lack of capitalization. I still have no problem correcting your grammar.
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