Trimming question

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hadmanysons

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After trimming a bunch of 30-06 cases to length today, using the Lee trimmer in a power drill, I chamfered and deburred. I was careful not to create a "knife" edge but when it came time to seat a bullet I noticed that some of them were a little stiffer to seat than the others. Upon closer inspection I notice flakes of the copper jacket on and around the case mouth. Did I cut to sharp and edge on the mouth or not enough? What did I do wrong? This didn't happen to the brass that didn't need trimming.
 
What are you using to chamfer the inside of the case neck? If you are using a standard cut chamfering tool you might need to consider switching to VLD tool.
 
I am using the Lee chamfer tool that came with the Challenger Kit. I'll admit it's a little crude but I was careful to make it as smooth possible.

Why is the VLD tool that much better?

There were shavings sticking to the inside but I wiped them out with a Q-tip.
 
It takes a sharp edge to shave jacketed bullets. Find it, eliminate it. One reason I always tumble after trimming and chamfering/deburring. Helps tone down edges by getting rid of very fine pieces of brass hanging one and polishing off those corners just a hair. You have to start with a good job of trimming/chamfering/deburring of course.
 
Part of my process after chamfering and deburring is to shoot a blast of air through the primer hole and make sure the case is clear of everything.

I have compressed air available in my shop and I just sit there with a big bowl of brass and blow them out. I pick up maybe 4 cases at a time and just shoot a quick blast through each case. It's amazing what comes out sometimes.
 
Sooooo.... Am I doing it to much or not enough? Sorry about the mspaint picture here but my camera wouldn't focus on the case mouth for some reason. That's a close approximation of how much I am chamfering and deburring.
 

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Chamfering should be done very sparingly...just enough to remove the sharp edge inside and outside of the case mouth. The remaining flat surface should be virtually the same thickness as the case. Otherwise, for one thing, it will be difficult to get a good crimp.
 
I know it's hard to do, but I try to avoid a "knife edge. I just want the corners off to avoid shaving the bullets and to guide them a bit easier. I'm not even sure if it's worth doing the outside at all. It should never touch the bullets in the first place. At least in theory.

Basically what tootaxed said, but worded different. Hope I helped.
 
"Way too much! GFM WOODCHUCK is correct...the outside doesn't really have to be chamfered at all. But I guess I have a thing about sharp edges...I just touch the outside enough to dull it. Thinking about it, same with the inside edge!:scrutiny:
 
I'm not even sure if it's worth doing the outside at all. It should never touch the bullets in the first place. At least in theory.

With brass that has not been trimmed, it's not a big deal, but with trimmed brass I disagree for a couple of reasons.

After trimming there will be a jagged edge inside and out, with little shards etc clinging to the edges.

Those pieces will come off sooner or later, possibly in your chamber or barrel.

If you are crimping, it will interfere with the crimp, as well as at least partially shaveing off those little pieces getting into dies etc.

After trimming brass I always deburr and chamfer, as well as tumble to get rid of little clinging pieces of brass and further smooth the edges that have been deburred and chamfered.

But I guess I have a thing about sharp edges...
Me too.
I just touch the outside enough to dull it.
I also just touch it a little. I do it enough to remove trash from trimming and just take off the 90 degree edge left from trimming. I only lightly do the inside as well.
 
I use the Lee in a drill also, and after trimming I use an RCBS chamfer tool to debur in & out (I also use an RCBS flash hole tool). I have learned through experience to just "touch" the neck and avoid the knife-edging mentioned. If you leave burs, or sharpen the neck it can scrape the bullet. I used to use a Lee chamfer tool but it was a bit too conservative for me; the RCBS tool can be too aggressive with a heavy touch. It's a matter of what you can use comfortably and get the job done. Done correctly, trimming need not leave burs, but tumbling is always an easy follow-up.
 
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