For those that load 223 Rem/5.56 for semi autos

[cptdco]

if you watch the video, note that the outside diameter of the case-trimmer (inside diameter of the power adopter) is the same as the deburring / chamfering tools made by (I think) RCBS and others.

 

[bgrafsr]

I use the Dillon case trimmer for my semi-auto brass. Sizes and trims in one step and it's quick.

 

[Win75]

Sir, when I was competing with the AR, I full-length resized and trimmed after each firing (not necessary for a bolt gun). I do the same for Garands, M14 types, etc. FWIW, the Palma bolt gunners I know follow a cycle of four or five neck sizings to one full-length resize, and then repeat the cycle.

For trimming and case checking, I used a cheap piloted Lee hand trimmer and a Wilson case gauge. Many high power guys use powered case trimmers such as the Gracey or Giraud, but they're expensive--really not cost-effective unless you're dealing with thousands of cases.

Hope this helps, and Semper Fi.

Ron H.

I don't shoot AR's in competition but I do shoot quite a bit so the above answer fits me also.

I neck size for my bolt guns and only check the length occasionally.