223 case length question

[RVenick]

I finally bought a AR15 and I am going to start loading 223. I have some range brass that I have picked up over time. I started to process some it today. I ran it thru the tumbler. I got my caliper out and started checking case lengths. Here is where my question comes in. I know from my manuals that the min/max is 1.750/1.760 respectively. Out of the 270 cases I checked 68 were too short, most by only a few thousanths but a few were as short as 1.740. Are these any of these cases not usable? I will for the most part be using these cases for plinking and playing at the range I am not into hole in hole accuracy but at the same time don't want them all over the place.

 

[Schwabee1]

Clean the cases then run them through you full length sizing die before you waste your time measuring their length. They will get a little longer when sized, then worry about trimming them shorter.

 

[Walkalong]

Yep.

Size them first, then measure them. Trim to 1.750, load em, and shoot em.

 

[RVenick]

Thanks for the replies I should be getting my die set later this week and will proceed from there.

 

[Damon555]

Even after you size them don't worry about the short ones....Unless it's a very large amount. A few thousandths short won't hurt anything.

 

[Shawn Dodson]

The "short" ones expanded to the diameter of the gun's firing chamber when the cartridge was fired, which caused the case to "shrink" in length. When you size them you'll push the case walls back to specified diameter and they'll "grow" in length as a result.

Cheers!