I was just decapping and neck sizing some 17 Rem FB brass and was checking the OAL of them and they are averaging about 1.410". The suggested OAL is 1.400". I use a LEE trimmer adapted to a RCBS case prep centre and have a .221 Fire Ball trim length gauge, but it is 1.390". With a piece I found that measured 1.407" there is some resistance on closing the bolt. Is it wrong to trim the brass 0.010" too short? Will it cause undo stretching of the brass? Will the earth's rotation cease? Thanks in advance.
Trimming brass to length question
- Thread starter KDX
- Start date
Going 0.010" under will have no effect at all. The only time case length is an issue is if you can't chamber it properly (as you note with the 1.407" piece) or if you are crimping, then they all need to be the same length so the crimp is consistent.
Are you sure your long piece won't chamber because of the neck or does the shoulder need bumping?
Mark
Are you sure your long piece won't chamber because of the neck or does the shoulder need bumping?
Mark
No idea. Maybe I should FL size one and see.
edit....bumping the shoulder back helped. I should have figured that one out in my own. However I can't trim them to length now because the gauge doesn't fit after neck sizing so they are going to be a little long.
edit....bumping the shoulder back helped. I should have figured that one out in my own. However I can't trim them to length now because the gauge doesn't fit after neck sizing so they are going to be a little long.
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I guess you have 2 options. Trim before resizing, or remove a bit off your trimmer pilot so that it fits in the case mouth. Maybe you need to chamfer the mouth of the case a bit to let the trimmer in. Too long of a case can cause pressure problems.
Most if not all reload books recommend a a trim to lenght below the optimum lenght. That way you don`t have to trim every time you load a round. It is strictly up to you if you don`t mind trimming every reload then by all means do so. Just don`t go over max lenght, a long neck can raise pressures fast. To be fair you don`t want to trim to much as you could start to erode the neck area in the chamber. Kind of like shooting shorts in a long rifle chamber. As for the benchmark what is the starting load that Hodgon has, they usually list both start amd max.
Your cases will grow more from resizing than they will from shooting them. They should be trimmed after resizing. If your pilot doesn't fit you may have to take some 180 grit emery paper to it while spinning it in a drill chuck.
