9mm trim length

B

bobc

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I am just getting set up for reloading 9mm. My foster trimmer only has one Collete (that wont fit 9mm)and collates are not available locally, so I went and bought one of those Lee case trimmers . My reloading manual lists 9mm trim to length at .751, the lee trimmer trims them to .744, is this OK or should I make a shim for the cutter so it will cut to .751? I will definitely have to make a handle for that thing 50 cases done 800 to go oh the blisters!
PS. yes I'm trimming my 9mm brass, yes I am that anal. ;)
 
I have never trimmed a pistol case, they get shorter when you shoot them. You are waisting your time trimming them.

Andy
 
I dont trim because cases are too long I trim so I get a consistent crimp. The first time I reloaded 45acp I had 5 boxes of brand new ww brass lengths varried by as much as .012" I did not have a trimmer then so I seperated them by length and adjusted my die for each length. The last thing I want is a lightly crimped bullet pushing back into the case and increasing pressures to the point wher it might blow up my pistol. Any way that is why I trim and realy I'm just wondering if .744" is to short for 9mm cases?
 
Good luck having blisters trimming the rest of your cases, but as the experienced handloader in here are telling you, trimming your cases for pistol calibers is a waste of time.
 
The only time I've ever run into a shooter who needed to trim pistol brass, it was Tanfoglio headstamped 9x21. The brass was probably fine, but the custom cut P9 barrel was likely short chambered.
 
bobc

All you want to do witht he .45acp is remove the belling. The cartridge calls for a taper crimp NOT a rolled crimp. The bullet is held tight be the walls of the case. The .45acp headspaces off the mouth of the case hence the absence of the rolled crimp. So Too, the 9MM.

You will never have to trim either cartrdige case. Straight walled cases tend to shrink not lengthen with resizing unlike bottle neck rifle cases.

As to consistency, I have shot mixed brass of varying lengths in .45acp and measured the velocities achieved and consistency with tests of cases of the same make and length and have found no noticeable difference in standard deviations or extreme spreads shot over my chrony.

Take Care

Bob
 
I Suddenly Feel Sick!!!

ALL THAT BRASS ALL THAT TIME!! YEA YOU LAUGH YOUR A## OFF. I went to the basement flared an empty 45 inserted a 200grn lead swc raised it till just before the crimp, took it out placed tip on reloading bench pushed down with as much force as I could and it did not budge.I always thought the taper crimp was the crimp at the end of the die I did not realize the die is capable of both types of crimp! THANK YOU ALL Very Very Much!! I'm feeling better now because I now have 800 9mm brass I DONT have to trim!!:dancingbanana: :dancingbanana: :dancingbanana:
Thanks again
 
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