Just wondering at what point is it necessary to trim your cases, I have heard some people say you can get away with firing it once or twice before trimming.. others say more often. At what length over the supposed length do you guys trim your cases? Lets say for example a 223 round is supposed to be 1.760" how much over that do you let it get before you trim.
At what length to trim cases?
- Thread starter Matty308
- Start date
I trim every time that I bump the shoulders or do a full-length size - usually takes 4 firings but sometimes less. I find that unless I FL size, the cartridge length does not change much.
My thinking is that I want consistency in neck length so that the bearing friction of the necks of each case is as similar as possible. Even so I would not let the case neck get longer than 10 thousands over SAAMI spec.
My thinking is that I want consistency in neck length so that the bearing friction of the necks of each case is as similar as possible. Even so I would not let the case neck get longer than 10 thousands over SAAMI spec.
With bottle neck cases, if you use the same brass from YOUR rifle, you can neck size only and cut down on having to trim the case. I'm on my 4th or 5th firing on some of my 308Win cases and haven't needed to trim yet. I did anneal them after the 5th firing.
With an AR, a fellow CGNer said I could get away from FL sizing and trimming if i just neck size only, just like how i do my 308. I did 20rnd from my AR and sure enough, zero feeding issues with neck sized cases. I did some research with regards to neck sizing AR cases and most recommend doing a FL size after the 4th or 5th firing.
If you crimp (as in shooting from an semi-auto), you'll want all your cases to be the same length so the crimp is even throughout your batch.
With an AR, a fellow CGNer said I could get away from FL sizing and trimming if i just neck size only, just like how i do my 308. I did 20rnd from my AR and sure enough, zero feeding issues with neck sized cases. I did some research with regards to neck sizing AR cases and most recommend doing a FL size after the 4th or 5th firing.
If you crimp (as in shooting from an semi-auto), you'll want all your cases to be the same length so the crimp is even throughout your batch.
I usually trim my .308 cases about every 3 years (I have 2400 Lapua cases
)
Trim length by the book says 2.005" but I trim mine to 2.000". I have fired cases as long as 2.025" in a match chamber without a problem.
)Trim length by the book says 2.005" but I trim mine to 2.000". I have fired cases as long as 2.025" in a match chamber without a problem.
When they get longer than the max length given in your manual. Cases usually stretch the most on their first few firing and sizing. Handgun cases don't stretch much at all. Remember you have to chamfer and deburr bottle necked cases too.
1.760" is the maximum length for a .223 case. When the cases get longer than that, trim them .010"-.015" shorter.
I have a Giraud trimmer, so I find it fastest to just trim every firing, rather than measure cases and trimming the ones that are too long.
