Chamber Question

[aggie99]

I have a question for all the smiths out there. I have a 1903a3 that I shoot 165 BT's over 57.5g H4350. All cases were full length sized @ each loading (I just got in a neck die for the 06). Some of the cases are Winchester and some are R-P's. The Winchester brass is separating at the head on the 3 or 4th firing. Also when comparing once fired rem brass out of of my gun to once fired rem brass out of a rem rifle my brass is about .03 larger at the case/head junction (where the seperation is occuring). Also there are striations that circumvent my brass which are much more pronounced out of my gun than the Rem. So is the .03 a significant difference in chamber diameter? Is the rougher chamber causing the seperation? Is it simply a difference in brass? O.K. thats more than one question but any explanations or opinions would be greatly appreciated.

[Coyboy]

Yes .030" is a huge amount in chamber dimensions, at the web (I don't think you meant head) I have no experience with you rifle in factory configuration so I can not comment as to weather that is original design or not. What you must remember is that a battlefield rifle is designed to shoot every case just once, not many soldiers wait around for the fight to stop so they can grab brass. Your cases are being worked excessivly at the web, and you may also have excessive headspace, exaserbating the problem.

You may be able to extend brass life by neck sizing only, check the fit into the chamber after neck sizing but before loading. After 3-4 neck sizings the fit may get too tight to function reliably and you will have to use your full length die.

Don't set the FL die up to meet the shell holder, start about .050 off and then test the brass fit to the chamber. Size a little deeper and try until it fits with minimal sizing.

Personally, I'd retire the thing.

[aggie99]

Is it difficult or costly to rebarrel an 03. The gun still shoots ~1" with handloads so i'd hate to get rid of it but also I do not want to throw good money after bad.