MontyF, the unsupported case case problem is more about a problem that is repeated over and over based on what someone heard or read and did not understand what they were being told or did not read the sentence before or after 'unsupported case head. I have never found an 03 or 03A3 with more than .090 thousands case head protrusion (+ or - very few) when measured from the bottom of the extractor grove cut in the head of the case, meaning more of the case head is supported than the .090 indicate. Given the fact the Mauser unsupported case head is .110 (+ or - very few thousands) plus head space the unsupported cases head for the Mauser is greater. Of the Mausers + or -, it is rare to find one with +.005.
But just in case I measure the thickness of the web from the head of the case to the top of the cup in the bottom of the case, military brass like LC measures .200, I have read unsupported case head on the 03 can be as high as .175, if that were true only .025 of the case head would be supported and if a heavy load was fired and the column of brass (case head)would be crushed/yielded the results could be catrophic, not a recommendation but just in case the chamber allowed the .175 unsupported case head commercial R-P brass would be a better choice, the P-P commercial case head is .260 thousand thick, in any event the R-P case would have more case head support.
If Springfield, no had Hatcher decided unsupported case head was a problem he could have designed a go-gage that would check for the maximum unsupported case head allowed based on the thickness of the case head or they could have designed the tool to mimic the unsupported case head of the Mauser.. Mauser had a flat face on the barrel and Springfield had a cone, so the tool would require a radius.
I have tools with out instructions, they are unfinished and were used in arsenals, that leaves me with guessing how the tool was used, I have taken some to gun shows and with a lot of time ask resource people if they could help in identifying the use of the tool, so far no no one has a clue, with one exception, Don Wooldridge a collector, resource, builder of 03s, 03A3s and Mi s said he saw a picture of one of the tools in Bophrie's book. Anyhow, I can check case head protrusion, ream a chamber with a pull through reamer, and check head space with two of the tools, another tool has to be a tool that checks the space between the bolt face and and cone, something like ' if the bolt closes on this tool, there is too much unsupported case head. again, the tool does not indicate 'how much' so the person using the tool has the opportunity to be creative.
Last edited by fguffey; 04-29-2011 at 11:47 AM.