Sizing Question

[otisrush]

Setup/Context: 9mm; RCBS Carbide Dies; Single Stage Press

The other night I noticed I was getting a few rounds that weren't dropping into my case gauge all the way. I rechecked my sizing die and noticed that the bottom of the die wasn't quite to the shell holder. So I adjusted the die down until it touched the shell holder per RCBS instructions.

I still get an occasional case that won't quite go all the way into the gauge after sizing. What's the deal? Are there some cases that just won't size like they need to?

OR

 

[BigBore45]

Try running them through the sizer again and see what happens. If they fit your gun and have good neck tention its no problem to use them. Some brass springs back more than others, some brass may be to thick and your expander is taking it to far. Might also need a small base die set or mill a bit off of the shell holder.

 

[misterarman]

Could be a length issue but with 9mm I don't find much overlength.
Could also be case bulge from an unsupported chamber.
Or what I find most often is the extractor is damaging the rim or leaving marks to prevent the case from going into case gauge all the way.

Not an expert on solving problems but it sure seems I'm overly experienced at encountering them.

 

[Free&Cold]

Are you talking about sized cases not fitting or finished cartridges?
If cases, check length.
If cartridges, check length and amount of taper crimp (check diameter of case just at neck).
If cartridges it could also be the diameter of the bullets or thickness of brass causing the diameter at the neck to be too large.

Good luck. Happy 4th of July.

 

[higgite]

Try inserting the cartridge into the gauge "backwards" to check rim size. Sometimes the rim is too big to let the cartridge go all the way into the gauge, but still works fine in a pistol. At least, that's been my experience. ymmv

 

[moxie]

"Might also need a small base die set or mill a bit off of the shell holder."

Never seen small base die for pistol brass.

 

[Walkalong]

Assuming you are talking about sized and not loaded brass failing the gauge.

I lose about 10% or so of range brass because it will not size down enough to pass my Wilson case gauge. Could be over pressure loads, sloppy chambers, who knows. No big deal, I have lots of it. That said, the same brass that failed the gauge, unless it is just horrible, will chamber in all but one of my 9MM handguns, an EMP with a SAMMI minimum chamber. Anything that fails the case gauge (Always near the case head) will jam up the EMP, but run in other guns. I toss it because I don't know what it will be fired in.

Over pressure can cause a bit of a bulge near the case head as well, enough to resist sizing. I don't want that brass. I figure it it has been stretched enough to resist sizing I don't want it, even though there are ways to get it sized down. I have plenty of 9MM brass, so I have this luxury.

Lee makes an undersized 9MM sizer that might help a little and save a case or two. I use my regular Lee sizer though, and have no plans on getting a Lee "undersized" sizer.