I expanded the case mouths on two different straight wall pistol cases (about 100 each). With all of them a very tiny amount of brass shaved off the case mouths. It was almost unnoticeable looking at the cases. But the brass was ultra lightly piling up on the press. I only expanded just enough to get the bullets barely started. Is that normal? It was once fired brass for one of the cases and new brass for the other. Should I have lubed them? Is that a reason to chamfer case mouths?
Case Mouth Expanding
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nettlle
Contributing Member
Expanding is to prevent any small amounts of anything getting shaved off. Set your expander die to flare the case a little more.
Some possibilities:
Does the case expand smoothly & quietly or does it make a scraping sound?
The case may not be entering the expander plug perfectly centered. Or the expander plug in your die may be off center. Make sure to tighten the locking ring or locking screw to keep everything in place.
The particular batch of cases may have slightly thicker cases.
You can slightly chamfer the inside & outside of the case mouths. I had to chamfer my 500 S&W cases when they were new. Very little is required.
Does the case expand smoothly & quietly or does it make a scraping sound?
The case may not be entering the expander plug perfectly centered. Or the expander plug in your die may be off center. Make sure to tighten the locking ring or locking screw to keep everything in place.
The particular batch of cases may have slightly thicker cases.
You can slightly chamfer the inside & outside of the case mouths. I had to chamfer my 500 S&W cases when they were new. Very little is required.
There is a sound but not one that I would normally call a scraping sound. So yes, there is a friction sound, but in a mild way. All lock rings were tight and I tried fine tuning the adjustment both ways to no avail.
Otherwise the die is a brand new one by Redding. Nothing looks out of wack but I suppose one never knows just eyeballing it for straightness. All bullets ultimately seated beautifully.
Otherwise the die is a brand new one by Redding. Nothing looks out of wack but I suppose one never knows just eyeballing it for straightness. All bullets ultimately seated beautifully.
At what point exactly are you getting the shaving?
If it is while expanding the case mouth, deburr the inside of the cases first. Did you trim? If you did, you absolutely need to chamfer/deburr the cases, inside and out.
https://www.midwayusa.com/product/789334/le-wilson-chamfer-and-deburring-tool-17-to-45-caliber
If it is while expanding the case mouth, deburr the inside of the cases first. Did you trim? If you did, you absolutely need to chamfer/deburr the cases, inside and out.
https://www.midwayusa.com/product/789334/le-wilson-chamfer-and-deburring-tool-17-to-45-caliber
Longhorn 76
Member
I get the same sometimes with my Redding profile crimper. I think it is knocking the outer corner of the case neck. If I lightly chamfer the OUTER edge, it goes away.
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