03-14-2022, 02:39 AM
(This post was last modified: 03-14-2022, 02:43 AM by r.tenorio671.)
....a "Headspace" gauge measures the distance from the bolt face to the the datum line of the shoulder & base of casing neck.
...a majority of ammo manufactures will bump the shoulder (datum line) of cartridges to the SAAMI spec, typically closer to the minimum spec of 1.183" to ensure it will properly chamber in ANY manufacturers barrel as long as the barrel maker kept to the SAAMI specs when reaming the chamber.
...if you have already measured the referenced ammo and the measurements fall within that 1.183" - 1.190" range, you should have no issues chambering & firing those rounds. What you want to do is after firing those rounds is to measure the cases afterwards to determine what your chamber was reamed to by the manufacturer so you can adjust your sizing die accordingly.
....brand of HS gauge will be a factor, some gauge manufacturers will machine to various specs within that 1.1901 - 1.2001" SAAMI Chamber specification allowance.
...won't let me add graphics again, dang it! I post graphics separately of the CARTRIDGE and CHAMBER specs.
Cartridge spec, note colored boxes...
Chamber spec, note colored boxes:
...a majority of ammo manufactures will bump the shoulder (datum line) of cartridges to the SAAMI spec, typically closer to the minimum spec of 1.183" to ensure it will properly chamber in ANY manufacturers barrel as long as the barrel maker kept to the SAAMI specs when reaming the chamber.
...if you have already measured the referenced ammo and the measurements fall within that 1.183" - 1.190" range, you should have no issues chambering & firing those rounds. What you want to do is after firing those rounds is to measure the cases afterwards to determine what your chamber was reamed to by the manufacturer so you can adjust your sizing die accordingly.
....brand of HS gauge will be a factor, some gauge manufacturers will machine to various specs within that 1.1901 - 1.2001" SAAMI Chamber specification allowance.
...won't let me add graphics again, dang it! I post graphics separately of the CARTRIDGE and CHAMBER specs.
Cartridge spec, note colored boxes...