Here'a a basic question about case trimminglength.... I know case length should not exceed the spec listed in reloading manuals, but how short can you trim it?

WHAT DOES YOUR RELOADING MANUAL(S) SAY?

When your reloading manual says "Minimum Trim Length" They mean it. Don't trim any shorter than the "Minimum Trim Length"

ZM

P.S. Just between you, me and the fencepost. please re-read the part of your reloading manual that has the step-by-step instructions for assembling your own ammo.

If your manual doesn't show a "minimum trim to length" or a "trim to length",(some don't,and the "0.010 rule of thumb" isn't shown in any of my 7-8 manuals)it should give you a "max CASE length"(not the max CARTRIDGE length).Take the MAX case length and trim 0.010 . Example, the max case length for 308 Winchester is 2.015-trim it to 2.005 minimum.The max case length for 30.06 is 2.494-trim it to 2.484 minimum.
And regardless,if you don't know,DON"T hesitate to ask.
Jeff

I suggest you do not trim more than to minimum length. My chambers allow much longer cases than the specs indicate, leaving a small portion of the bullet unsupported in the neck of the chamber. Not desireable, so I do not trim until cases reach maximum length in my chamber (wich only happens with cases reformed from another calibre with longer cases).

You can buy a little steel/lead calibre size plug from Sinclair to measure the actual case length your chamber will allow. In my experiende most chambers are longer than specs. indicate, but you have to measure, do not make guesses about this crucial dimension.

Tron

Thanks. I have been scouring my Nosler #4 manual. I didn't find the "minimun trim to length" anywhere in there. I didn't even see where the max trim length was given. Can I assume that the max length is the case length portion of the diagrams for each cartridge?

Yep,the case length of the diagram is max,actually the # 4 is one that I was citing that doesn't give the trim to length.If you fire any factory ammo,you may find that even after resizing,its shorter than the minimum length. Don't worry about it,it'll stretch.Oh yeah,always size or resize the case before trimming,even with new brass.You should pick up a couple more manuals,if you only have the one,for cross reference.Hodgdons # 27 is good as it shows a good variety of powders and bullets.And theres a lot of load data at the powder co. websites and some of the bullet co.s.
Jeff
http://www.hodgdon.com/data/index.php
http://www.alliantpowder.com/
http://www.imrpowder.com/