I have a 5 gal bucket of military brass that I have not yet sorted, but I am sure some of them will be too thick for proper function and safety if used as is for 300 blackout brass. People sort them according to head markings. Sounds like to me the loaded rounds should be checked any way.
Question: People claim that it is not practical to reduce the case neck wall thickness. Is it that hard to use a .308 reamer on a sized case that has not yet had the neck expander through it to get the right wall thickness. Other than the work is there any other downside to reaming overly thick case neck walls. I have ordered a tube micrometer to measure case neck thickness
Question: People claim that it is not practical to reduce the case neck wall thickness. Is it that hard to use a .308 reamer on a sized case that has not yet had the neck expander through it to get the right wall thickness. Other than the work is there any other downside to reaming overly thick case neck walls. I have ordered a tube micrometer to measure case neck thickness
Use only cases with the proper wall thickness. Take a look at the chamber drawing in Figure 1. Notice that the diameter of the chamber at the location of the case neck is 0.3350". Since the bullet has a maximum diameter of 0.309", that leaves only 0.026" of total space available for the brass. There should be about 0.002" of total clearance around the neck for reliable feeding, so the maximum case wall thickness is about 0.012". Keep in mind that 0.012" leaves almost no room for irregularities in case concentricity, so in reality you're better off with cases that are slightly thinner than this; a 0.0110" to 0.0115" wall thickness is just about perfect.
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