PDA

View Full Version : Fully supported chambers


Bob Thompson
March 3, 2000, 01:05 PM
I just visited Alliants web sight to get updated loading on some new powders and found certain maximum loads for pistols suggested these max. loads for use in fully supported chambers only. Now it seems to me that any autoloader because of the feed ramp would not have these chambers and only revolvers or single shot pistols would. Can anybody add some insight to this problem. Thanks much,Bob

James K
March 3, 2000, 01:25 PM
Fully supported need not mean right up to the rim, as in a revolver. If the case is supported up onto the base (the solid part) of the case, there should be no problems.

But in a normal case, the case sidewall tapers. If the case is left unsupported at the point where the brass thins out, there is a potential for problems with high pressure loads. You can determine for any cartridge where the solid part begins simply by measuring the depth of the inside of the case and comparing it with the length of the outside.

Jim

George Stringer
March 3, 2000, 11:09 PM
Bob, there are semi-auto barrels with fully supported chambers. Any ramped barrel is fully supported and at least one semi-ramped, Clark I think, is fully supported. George