Case length for 9mm

[no_agenda]

For some reason my spent cartridges are measuring form .740-.749 yet Lyman lists lengths .751-.754. What's going on? Is it my caliper (brand new lyman stainless steel)? Or is this ok? I am measuring federal once fired brass. Thanks.

 

[helg]

Do you measure the brass after sizing? The sizing makes brass longer. If it was fired from a loose chamber, the difference before and after sizing may easily be .01".

 

[no_agenda]

No it is before sizing them

 

[rjbishop]

Read your reloading manual front to back? Your 9mm brass is still easily in spec- it will likely stay that way for several firings. Rarely need to trim straight case pistol brass.

For the record, Max length for 9mm Luger is .754, and trim length is .744.

 

[1SOW]

My 9mm (1000's) read about .748-.749 'after' resizing. I shoot a CZ with a fairly tight chamber and recover my brass. Some have been fired "many" times.

The Lee manual says a new case is .754. Maybe my dig caliper is off too.

I've reloaded and shot many 1000's of these with no problems, but I load at the lower end of the charts for comp.

If I was going to load very hot rounds, I might look deeper into the question .

 

[918v]

9mm brass varies in length all over the place. I had some R-P brass that measured as short as .739" and some FC that measures as long as .756". You should measure brass after sizing.

 

[no_agenda]

Thanks for the info guys, I'm slowly but surely gettin the hang of this...

 

[Seedtick]

You will find that a lot of pistol brass will actually get shorter after firing it. This is more noticeable the larger the firing chamber is. Not a problem though.

ST

 

[Walkalong]

Yep. Shorter when fired, longer when sized. Measure after sizing.

Easiest thing to do is not measure any of them and quit worrying about it. I know I don't. Load em and shoot em.

I trim all revolver brass to get a more comsistent crimp. I never worry about auto brass.

 

[The Bushmaster]

9mmX19 case length? A lot of worry about nothing. Load'em...Shoot'em...Load'em again. Can't remember the last time I measured a 9mm case. Can you Walkalong?

 

[Walkalong]

Nope