Trimming & Annealing Case Necks

[Appleseed]

What is the correct way, anneal 1st and trim necks 2nd, or the vise versus?

[Elkbane]

Here's how I do it.

Deprime the fired cases.
Anneal them
Size them
trim them

One of the purposes of annealing is to get the neck/shoulder to consistent "softness" so that you get uniform base to shoulder dimensions when sizing. Once that is achieved, you can trim them to uniform length. If you trim them first, due to differential "springback", after sizing the annealed cases you'll put length variability right back into them. At least that's my theory (I've proved it to my satisfaction with WSM cases) YMMV......

That didn't read well... here's an explanation
(On WSM cases that need annealing, after sizing I can get as much at 1.5-2 thou headspace variabiity case to case - the "stiff" ones just don't size well, but the "soft" ones size OK - after annealing they are all w/i half a thousandth - If I trimmed first, that length variability would show up in the cases - some with long necks and some with short, which affects bullet release which is a function of neck tension and bearing surface contact along the length of the neck)

Elkbane

[Appleseed]

Shall term this method "A S T."

Off to the loading S H E D.

Thank You, B O E.

[R1]

I've had nothing but problems trimming and chamfering annealed brass. Cutting blades have a tendency to really bite and dig into soft brass. I now resize, trim, then anneal.

[Bad Water Bill]

IIRC back in 1965 when I got my Forster trimmer the instructions read and still do, trim or ream before sizing. Somehow my pilots and reamers will not fit in sized cases. Also the outside neck turning pilots will not fit in a sized 20 VT, 22 Hornet, 218 Bee, 221FB, 222, 223, 22-250 etc. What am I doing wrong that I must work them before sizing?

[Elkbane]

Here's my rationale for the statements I made above- choose a method that works for you.

I use the Forster trimmer in .22, 6mm, .284 and 30 cal. Without exception, all trimmer pilots slip-fit in sized cases but are "sloppy loose" on fired cased. If the case neck isn't tight to the pilot, you can get the case canted in the bushing which holds the casehead and trim the case neck on an angle. That, and the fact that headspace isn't similar case-to case, is why I ALWAYS trim sized cases.

If you think fired cases all have the same headspace - ask anyone who neck sizes only what symptom causes them to F/L size their cases. It's when "some" of the cases exhibit hard chambering. Well, if some chamber hard and some don't, then that means the shoulder is farther forward on some cases than others. If you trim to the same OAL dimensions (base to neck) in this condition, then size them, you'll transfer whatever length variation was in the headspace (Base to shoulder) to the total length of the sized case. For each his own.

WRT neck turning pilots - in order for them to fit you need a neck expander mandrel of the proper dimension. I usually size the case without the expander button, run them over the expander mandrel, then they fit well on the neck turning pilot.......
Elkbane