Hello all. Forum newbie here so please excuse any breach of etiquette. I'm considering rechambering my modern rifle to a somewhat obsolete cartridge. I am trying to understand how a gunsmith would cut the new chamber. I have done some homework-You tube videos, reading forums, emailing tool companies, calling gunsmiths- but some of these sources don't have time to educate me for free. The thing I'm stuck on is "how can a chamber be reamed to the proper depth when the headspace gauges for rimmed cartridges in the catalogs claim to be usable for multiple length cartridges?" (30-30 gauge claims to be usable for 375 Win, or in the case of belted cartridges 300 Win Mag is also used for 7 MM Rem Mag- which are different lengths. The 375 Win also has no shoulder.)
So I assume these gauges are used to get the headspace correct for a given rim thickness or belt dimension, but the question again is "how do we cut the proper chamber depth?" For rimless cartridges, all the videos I've watched show the gunsmith using a headspace gauge to cut the proper depth. This makes sense since the headspacing uses the shoulder as a reference, and there are no claims that this style of gauge can be used for different length cartridges.
Ok thanks. I'll probably post more about my particular project, but trying to understand this first. I chose the reloading forum for this, because I'll probably follow up with discussion of how to get my brass to fit the chamber.
So I assume these gauges are used to get the headspace correct for a given rim thickness or belt dimension, but the question again is "how do we cut the proper chamber depth?" For rimless cartridges, all the videos I've watched show the gunsmith using a headspace gauge to cut the proper depth. This makes sense since the headspacing uses the shoulder as a reference, and there are no claims that this style of gauge can be used for different length cartridges.
Ok thanks. I'll probably post more about my particular project, but trying to understand this first. I chose the reloading forum for this, because I'll probably follow up with discussion of how to get my brass to fit the chamber.