minimum case length

[unclejhim]

Reloading manuals show maximum case length and a trim to length. My question is what is the minimum length you can still use? Is it 1/10th under the trim to length 2/10th.....??? This concerns rifle only, actually 35 Whelen used in a break barrel. But I never seen anything mentioned on this...... curious.

 

[The_Shadow]

As long as the casing is between the maximum length and the trim length it will be just fine. Where things get touchy is the crimp process, longer cases get more and shorter get less, if you don't adjust the die settings...Most do NOT crimp their rifle cases, if they are bolt action or break open actions. Semi auto's would require some amount of crimp to avoid bullet movements due to the rough cycling!

 

[unclejhim]

That is all fine but it doesn't address the question. The question is.....can you use a case that is trimmed shorter than the "trim to length" and if so what is the tolerance?

 

[dougstump]

It all depends on the cartridge and if you crimp. With the cartridges that headspace on the case mouth (.30 Carbine, 9mm, 40 S&W, .45 ACP, etc.), if the case is shorter than the minimum (trim to length) then you will have excessive headspace problems. If the case headspaces on the shoulder (.308, .30-06, .356 Sig, etc.) or headspaces on the rim (.30-30, .303 British, .38 special, etc.) then your case length can safely be shorter than the minimum. However, if you crimp the rounds, inconsistent case length will give you problems. Did this help, or am I clear as mud?

 

[Request Dust Off]

How short are they? Why not just get new brass? I would scrap brass .100" to .200" too short.

There are a few things a reloader will do but may not advocate for fear of liability. I have never seen a tolerance stated for how far under the trim to length is acceptable. I think you might get a way with about .070" on a .223 and maybe .100" on the .35 Whelen at the very most in a desperate situation. But what if I am wrong? Even if you half that what if things go badly? How much are your eyes worth? Why even take a chance? If the loads are safe but suck you lost that much in bullets powder and primer anyway.
I would think .200" is too short to bother with. .010" - .020" would not give me a lot of concern but I would make every effort to correct it right away.

You need acceptable headspace and neck tension. Be careful the bullet doesn't stick in the rifling and pull out of the case.

2 rules of thumb:
- Have about 1X the bullet diameter in the neck as starting point.
- You should not be able push the bullet into the case.

The .223 & .30-06 X-dies for example run with brass cut .020 short of max length. No X-die for the .35 Whelen.

Ultimately you would have to make the decision. The safe bet is scrap them if too short by .100" or .200"

 

[Barry J]

How would a case get too short? I thought a case lengthened with each shot and needed trimming after 4 or 5 uses.

 

[Request Dust Off]

Probably the most common would be human error, as in to cut them too short when trimming.

I had some that are short. Once fired and a tad short. Never really thought much about it, just use the other ones I have. I segregate by headstamp and such so they are in a box by themselves waiting for a rainy day.

 

[unclejhim]

Barry a case can get too short by trimming to much off.
Thanks guys, I'm not using short cases ( not worth it) it was a topic I had never seen in any of the manuals and was just curious.

 

[Request Dust Off]

Well beside human error some trimmers have a way of not staying adjusted.

 

[Barry J]

Thanks. Didn't think it could happen during firing.

 

[highstandard40]

How would a case get too short? I thought a case lengthened with each shot and needed trimming after 4 or 5 uses.

Bottleneck rifle cases do lengthen but rimless pistol cases usually get shorter with repeated firings.

 

[noylj]

Bottleneck cases: since the cartridge headspaces on the shoulder, you can trim the neck to your heart's content--you will just be losing neck tension to hold the bullet and crimps will vary a lot unless you trim all cases to the same length.
Straightwall cases: Don't trim at all unless you are shooting a case with a rim for head spacing (see .38 Spl cases), in which you might want to trim to make the roll crimp more consistent. However, I have never found that this does any good--possibly because the bullet cannelure/crimp groove is much longer than the difference in case lengths.
Even Richard Lee admits that he has no idea why people trim straight wall cases, but as long as they want to, he will supply the tools.

 

[The_Shadow]

That is all fine but it doesn't address the question. The question is.....can you use a case that is trimmed shorter than the "trim to length" and if so what is the tolerance?

Most do NOT crimp their rifle cases, if they are bolt action or break open actions.

If your 35 Whelen case is spacing on it's shoulder (and it probably is), it will make do difference if it is shorter than trim length, in the break barrel action...so long as the cartridge is head spacing on its shoulder.