September 20, 2014, 08:21 PM | #26 |
Member In Memoriam
Join Date: March 17, 1999
Posts: 24,383
|
The coned breech (which was designed for easier feeding) is somewhat of a weakness, but with good cartridge cases is not a problem. The problem with the SHT 1903's was that if/when a cartridge case did let go, the sudden impact of that high pressure gas shattered the receiver, breaking it into pieces. We don't think of an invisible and sort of insubstantial thing like gas having an impact, but it does, and that impact is a very hard, fast blow, not a gentle push. And it is that kind of blow, whether delivered by a hammer or by fast moving gas, that breaks those brittle old receivers.
Make no mistake; ANY receiver on a rifle like that which has experienced case head failure would have been damaged, almost certainly beyond repair. The sidewalls would have been bent outward, the magazine bulged and the floor plate blown out, but a good receiver would have held together. The brittle ones didn't. Jim |
September 21, 2014, 09:16 AM | #27 | |
Senior Member
Join Date: July 18, 2008
Posts: 7,249
|
Quote:
More support, the P14 chambered to 303 British has a rim that protrudes and most of the case is supported by the chamber, a few of the P14 went through for repairs, some of the barrels had a gas escape cut in the face of the barrel in front of the rim and over the top of the chamber. then to really cut down on the possibility of hot, high pressure metal cutting gas escaping the British drilled a hold through the chamber in front of the receiver. that one drilled hole through the chamber dropped the price down from $400.00 to$50.00. F. Guffey |
|
September 21, 2014, 09:39 AM | #28 |
Senior Member
Join Date: July 18, 2008
Posts: 7,249
|
then there is the case, as I have said before in the form of a question "Who measures?" It is rat after that the snarky(s) get snarky. Military case heads have a case head thickens of .200", R-P commercial 30/06 case head thickness is .260" (there goes the theory surplus is thicker than commercial).
rather than talk about it I suggest someone purchase tools to remove a barrel, measure from the case head forward and from the front receiver ring back to the bolt face. With a military case and 1/10"? (.100") protrusion the case head is supported by .100". Meaning? It takes a lot of pressure to blow a plug out of the side of the case at the extractor cut. Then there is case head separation, and for me a boring story always starts with "Hatcherr said ...." F. Guffey |
September 21, 2014, 12:00 PM | #29 | ||
Senior Member
Join Date: November 20, 2007
Location: South Western OK
Posts: 3,112
|
Quote:
Quote:
|
||
September 21, 2014, 02:42 PM | #30 |
Senior Member
Join Date: July 18, 2008
Posts: 7,249
|
AND THEN?
There is crushing the case head. When the case head is crushed the thickness of the case head from the bottom of the cup above the web and case head is reduced. F. Guffey |
|
|