how short is too short

[flatsticks]

Recenlty trimmed up 100 , 6.5 creedmoor cases and after twenty or so cases I found about 10 of them were shorties. guessing my calipers were off maybe accounting for the shorter ones .
The minumum length per sami is 1.910 and i have been running them 1.920, shorties ended up at 1.880.
I know they will grow longer but what are the cons of shooting them that short or just toss them ?

 

[AJC1]

Recenlty trimmed up 100 , 6.5 creedmoor cases and after twenty or so cases I found about 10 of them were shorties. guessing my calipers were off maybe accounting for the shorter ones .
The minumum length per sami is 1.910 and i have been running them 1.920, shorties ended up at 1.880.
I know they will grow longer but what are the cons of shooting them that short or just toss them ?

You will have to clean the chamber .030 deeper and your cannalure may not match up. That's basically it.

 

[Charlie98]

If you aren't crimping, it probably won't make much difference... beyond what AJC suggested.

 

[243winxb]

The neck needs to seal the chamber on firing. Most will.

SAAMI minimum is 1.900" Below, watch for gas/pressure getting to the top of the should or onto the case body. Dents in the case shoulder or body are not good.

This (photo) mostly happens with big magnum cases, slooow powder, lite for caliber bullets & low bullet hold/neck tension.

 

[Charlie98]

Dents in the case shoulder or body are not good.

I don't know if I've ever seen that... not from gas leaking back. Interesting...

 

[AK Hunter]

The neck needs to seal the chamber on firing. Most will.

SAAMI minimum is 1.900" Below, watch for gas/pressure getting to the top of the should or onto the case body. Dents in the case shoulder or body are not good.

This (photo) mostly happens with big magnum cases, slooow powder, lite for caliber bullets & low bullet hold/neck tension.

View attachment 1111028

That dent should fire form out, I have done it on 7.62x54r brass with heavy dents.

 

[FROGO207]

My standard answer is what I learned from an old reloader some years after I had started and this question came up. As long as you have at least one caliber of bullet sidewall in contact with the cartridge neck you will have enough neck tension to hold your bullet safely. Crimping the bullet if you do that will be different at that length but as a rule I do not crimp anything unless it is used in a tube fed firearm or a revolver.

 

[kalielkslayer]

Just my opinion but I strive to get everything as consistent as possible. I’m upset if I can’t trim to within .0025” of each other. I don’t even like that much variation but have learned to accept it.

 

[Bfh_auto]

My standard answer is what I learned from an old reloader some years after I had started and this question came up. As long as you have at least one caliber of bullet sidewall in contact with the cartridge neck you will have enough neck tension to hold your bullet safely. Crimping the bullet if you do that will be different at that length but as a rule I do not crimp anything unless it is used in a tube fed firearm or a revolver.

I learned the same thing. I've been flamed for stating it in the past. But I've not had it fail me.

 

[BigBlue 94]

I learned the same thing. I've been flamed for stating it in the past. But I've not had it fail me.

The same theory applies to fasteners too. A 1/2" bolt needs about a half inch thick nut for proper holding strength.

 

[FROGO207]

The same theory applies to fasteners too. A 1/2" bolt needs about a half inch thick nut for proper holding strength.

Those pesky rules of thumb LOL. There are many in the trades I have picked up over the years.

 

[flatsticks]

Thanks for the advice everybody .

No cannalure to deal with which is a good thing .

No pressure signs previous but will keep and eye out for them and just shoot them at the range instead of hunting .

 

[Varminterror]

The “one caliber of bearing surface in the neck” mythos is pure bunk. It’s a cute rule of thumb, but really doesn’t hold water by any physical construct or any results on target.

 

[Walkalong]

It does, however, in general, pay to have enough bullet in the case/neck tension to hold bullets securely for most things besides target shooting.

 

[Varminterror]

It does, however, in general, pay to have enough bullet in the case/neck tension to hold bullets securely for most things besides target shooting.

Absolutely - but my point is that such really doesn’t have anything to do with the diameter of the bullet.

A 416 Stroker with a 500grn bullet seated to 1 caliber has 3.3x greater neck contact than a 223/5.56 seated to 1 caliber, but shoots a bullet with around 6.5-10x greater moment of inertia. 308win has about 80% greater contact over the 223/5.56, but 2.3x greater inertia. One end of this spectrum or the other is either grossly under gripping or grossly over-gripping, because the proportionality of inertia to gripping area isn’t constant.