Fatelvis
Member
I've been reading alot about measuring datum points on brass, and buying case guages, etc., for loading for the M1A. Do you really need a case guage? Please tell me if this method is wrong:
Clean the chamber well, remove the Op rod spring and extractor, take about 6 cases that were fired in the same rifle and put them in the chamber and see if the bolt closes on them easily. They never do. Start by sizing one of the cases (using a FL die), so it barely bumps the shoulder. Chamber the sized brass, and try closing the bolt. If it doesnt easily close, size it again, after lowering the sizing die 1/16 of a turn (.0045"). Try chambering the brass again. If the bolt doesn't close, size the brass after lowering the die another 1/16 turn, and repeat until the bolt closes. At this time, try sizing at least three of the other fired cases, and chambering them. If they don't chamber easily, lower the die another 1/16 turn, and make sure they will chamber easily. After determining that the sizing die is bumping the shoulder enough to permit chambering, lower the sizing die another 1/16 turn, to giving at least .0045" shoulder clearance.
I've done it this way for many years, and have never had a case sep, although I only loaded them 4 times after original firing, and only had 1 rifle. Thanks-
Clean the chamber well, remove the Op rod spring and extractor, take about 6 cases that were fired in the same rifle and put them in the chamber and see if the bolt closes on them easily. They never do. Start by sizing one of the cases (using a FL die), so it barely bumps the shoulder. Chamber the sized brass, and try closing the bolt. If it doesnt easily close, size it again, after lowering the sizing die 1/16 of a turn (.0045"). Try chambering the brass again. If the bolt doesn't close, size the brass after lowering the die another 1/16 turn, and repeat until the bolt closes. At this time, try sizing at least three of the other fired cases, and chambering them. If they don't chamber easily, lower the die another 1/16 turn, and make sure they will chamber easily. After determining that the sizing die is bumping the shoulder enough to permit chambering, lower the sizing die another 1/16 turn, to giving at least .0045" shoulder clearance.
I've done it this way for many years, and have never had a case sep, although I only loaded them 4 times after original firing, and only had 1 rifle. Thanks-