trimming rifle brass

dgac

I have some 222, 257, 30 06 brass. I'm new to reloading. I looked at the total length in my book. It said that the 222 have to be 1.70 and my once fired is 1.695 So is 1.70 my max case length? I checked a couple of peices of each and none of them are longer than the lengths in the book. Could they be too short? please educate me!!!

dgac

flyingtorpedo

Read the manual. It should tell you how to read the info. Most likely the info given will be the MAX allowed and if they need trimming .010 inches is to be removed. So I'd say you are under max and should be good to move on the the next step.

B17-P51

If you trim all the cases AFTER they have been resized to 1.690 or whatever the TRIM LENGTH is, it will square up all the case necks, and make all the cases the same length. This is important for crimping or if no crimp, more equal case neck tension. This equates to better accuracy. Also always trim in a batch then you will have to trim all the cases every 5 or 6 firings, more or less depends on your load and gun.

joes

cases stretch after firings and chambers on all gun are slightly different in size. The cases in those cases need to be trimmed if they stretch beyond the max lenght to cycle and functionly properly. I have cases that never exceed the Max and never get trimmed. The key word is "max", so if you are under that point you need not trim, but you could trim in order to square off as stated above.

JustC

brass is made so short now a'days, there is little chance of it being too long and being crimped by the leade and therefore running pressures up. I pick the shortest case in the lot (unless it is wayyy short of the rest, then I discard it) and trim all the cases to that length. Now they are all the same and will all need trimming at the same time from now on.

The books are very conservative in their figures due to too many lawyers and not enough shooters being employed. You can exceed the length in the books by a fair amount. I would run the longest case into the chamber and extract it, if there isn't a mark on the case mouth or a sign that it was actually impinged and crimped inward by contacting the rifling lands, you are good to go.

mrbruce

The above statement is the right way to deal with the problem that usually isn't there to begin with.....
I usually bore a large hole in the primer pocket and insert my borescope into the case to see exactly where the end of the case sets in relationship to the end of the chamber, and I've never seen one that was to long.....