9mm vs. .380 resizing

spacecoast · February 7, 2010, 04:51 PM

Using a hand press, it becomes painfully obvious very quickly that de-priming and resizing 9mm brass is much more difficult effort-wise than .380. Any plausible explanations as to why, since the cases are about the same size? The 9's are quite a bit harder than .45 ACP as well.

Sevens · February 7, 2010, 04:59 PM

9mm is a tapered case. Hard to tell by looking at it, but factory fresh spec 9mm is just a bit larger at the case head than at the mouth. Resizing 9mm is much like resizing .30 Carbine, but it's a little more difficult to tell.

Resizing tapered cartridges is more difficult across the board.

I am one of the few oddballs out there that uses a touch, I mean just a touch of lube when sizing 9mm. And YES, of course I use a carbide die. I also use it when I size 10mm and sometimes I use it for other handgun calibers, too. Not a lot! Just a touch. Sometimes I'll use it on some and skip a few and go without. It just absolutely makes the sizing operation smoother and easier.

And my tin of Imperial will last through the next 20 years, I think.

MR 8x57js · February 7, 2010, 08:50 PM

The 9MM brass is thicker in the mouth!

mete · February 7, 2010, 08:58 PM

9mm operates at higher pressure so it would have thicker case . It also has thicker case as it might be used in an SMG.

colospgsAVID · February 7, 2010, 11:49 PM

It will be ever more difficult to size a tapered case. IMO full length sizing a straight case is still basically neck sizing for the most part. I am like Sevens, in the fact that I will use a touch of lube in my sizing process on 9mm.

EDIT: Just makes it easier, less wear on the die, makes me feel better. Also of course carbide a die. If you do this you will need to clean and re-lube your die every so often. I clean all of mine fairly often.

Randy 1911 · February 8, 2010, 02:37 AM

If you compare the design drawings of 9mm and 380 acp you will see that the 380 is a smaller case diameter. Just a few thousandths, but smaller. You can't interchange the dies.

spacecoast · February 8, 2010, 06:09 AM

Quote:

You can't interchange the dies.

I wasn't doing that, just trying to find an explanation for the difference in effort required for what are otherwise very similar cases.

February 7, 2010, 04:51 PM	#1
spacecoast Senior Member Join Date: October 14, 2009 Location: Sunshine and Keystone States Posts: 4,461	9mm vs. .380 resizing Using a hand press, it becomes painfully obvious very quickly that de-priming and resizing 9mm brass is much more difficult effort-wise than .380. Any plausible explanations as to why, since the cases are about the same size? The 9's are quite a bit harder than .45 ACP as well.

February 7, 2010, 04:59 PM	#2
Sevens Senior Member Join Date: July 28, 2007 Location: Ohio Posts: 11,756	9mm is a tapered case. Hard to tell by looking at it, but factory fresh spec 9mm is just a bit larger at the case head than at the mouth. Resizing 9mm is much like resizing .30 Carbine, but it's a little more difficult to tell. Resizing tapered cartridges is more difficult across the board. I am one of the few oddballs out there that uses a touch, I mean just a touch of lube when sizing 9mm. And YES, of course I use a carbide die. I also use it when I size 10mm and sometimes I use it for other handgun calibers, too. Not a lot! Just a touch. Sometimes I'll use it on some and skip a few and go without. It just absolutely makes the sizing operation smoother and easier. And my tin of Imperial will last through the next 20 years, I think. __________________ *Attention Brass rats and other reloaders:* I really need .327 Federal Magnum brass, no lot size too small. Tell me what caliber you need and I'll see what I have to swap. PM me and we'll discuss.

February 8, 2010, 02:37 AM	#6
Randy 1911 Senior Member Join Date: May 7, 2009 Location: Western Arkansas Posts: 273	If you compare the design drawings of 9mm and 380 acp you will see that the 380 is a smaller case diameter. Just a few thousandths, but smaller. You can't interchange the dies. __________________ Been Reloading 27 Years NRA Member Member Old Fort Gun Club www.ofgc.org

February 7, 2010, 08:50 PM	#3
MR 8x57js Member Join Date: February 7, 2010 Posts: 36	The 9MM brass is thicker in the mouth!

February 7, 2010, 08:58 PM	#4
mete Senior Member Join Date: June 14, 2004 Location: NY State Posts: 6,575	9mm operates at higher pressure so it would have thicker case . It also has thicker case as it might be used in an SMG.

February 7, 2010, 11:49 PM	#5
colospgsAVID Senior Member Join Date: January 2, 2010 Location: Colorado Springs Posts: 188	It will be ever more difficult to size a tapered case. IMO full length sizing a straight case is still basically neck sizing for the most part. I am like Sevens, in the fact that I will use a touch of lube in my sizing process on 9mm. EDIT: Just makes it easier, less wear on the die, makes me feel better. Also of course carbide a die. If you do this you will need to clean and re-lube your die every so often. I clean all of mine fairly often.