Can someone tell me...

[chevy_dmax]

What the knurled ring or dotted band is for and actually called on like a .38 special or .357 mag casing? It kind of looks like a dashed line/ring/band around the case, say about a half inch from the case mouth (.357 mag). I've seen it on other brass too, even autos like .45 acp.

I originally thought it was something to control the bullet seating depth, but cannot find any reference to it anywhere. I've been searching the net, including here, for 2 days off and on.

I can't find a picture right now off hand, but I'm sure with the caliber (heehee) of people here, they can answer it.

Anyways, thanks in advance. I'm not too awful new here; I just don't post much at all. Also, I've only been reloading a few years, so I am still new compared to most on here. I am a little embarrassed to be asking what I assume is very simple question as I usually can search my way to most any information...this has whooped me though.

Bill.

 

[ReloaderFred]

It's called a cannelure. It was originally intended to keep a soft lead bullet from seating deeper into the case, but now has been relegated to more of a decoration. I've even seen cannelures applied near the base of the case on some .38's, which would serve no other purpose than decoration, or possibly identification.

Cannelures used to be common, but many companies have eliminated them, as it's just another step in the manufacturing process. If it's not needed, which is the case with proper neck tension and jacketed bullets, then there was no need to continue doing it.

Hope this helps.

Fred

 

[chevy_dmax]

Thanks, that makes sense. I would have never guessed it to be called a cannelure, go figure.

I have had some .357's become sticky to chamber after seating due to this cannelure cuasing the case to ever so slightly protrude there.

Thanks again,

Bill.

 

[G36Rick]

I actually have some .38's and .357 cases that have two cannelures one lower at the case and one higher...I'll dig through my bin and see who manufactured them and take a few pics.

 

[G36Rick]

Sorry guys,hard to see the cannelures.My digital camera doesn't have a macro lens.However,One case is a R&P and the other is a PMC both .38 Special.

 

[chevy_dmax]

I'll look tonight too, I'm not sure what cases for sure.......I do know some of the .357's are federal, nickel plated.

Thanks for the replies all.

Bill.

 

[Sediment]

The one on the left has the Cannelure, the one on the right does not. Both are .45 ACP, different weights and manufacturers.

478932[/ATTACH]"]

 

[chevy_dmax]

I'm refering to a cannalure on the brass itself. Thanks though.

Bill.

 

[Sediment]

Doh! My bad. Well at least a newbie reading this thread will know what a Cannelure is

 

[ReloaderFred]

That is a cannelure on a bullet, used for crimping into. He's asking about the cannelures on cartridge cases.

They're both formed the same way, but have different purposes.

With my C-H cannelure tool, I add crimping cannelures to bullets for special purposes, such as crimping into for 357 Sig and 9x25 Dillon, both of which have very short necks and little in the way of neck tension.

Hope this helps.

Fred

 

[ReloaderFred]

Don't be typing while I'm typing! That's rude..........

Fred

 

[Walkalong]

Yea Fred. Don't do that.

 

[chevy_dmax]

Well thanks to everyone for reading and for the replies. I found this (hope linking to this is okay) http://www.corbins.com/hct-1.htm

If you scroll down, its the last picture on the bottom right, its states right next to the picture, as ReloaderFred did, that it was/is/can be used to keep straight walled pistol bullets from seating deeper from the result of feeding the rounds. I also deduct from heavy recoil too, as this would sort of be a reverse roll crimp on the slug and still leaving the mouth of the case for use to headspace in auto's(?).

Its use has become completely apparent to me and I thank everyone. My problem I'm having with the sticky .357's is due to either:

1. The plated bullets being slightly longer than just pure lead, causing the bullet to be seated a few thousands deeper than the cannelure forcing it to slightly bulge there.
2. The casings' cannelure is too high to seat 158 grain slugs and could have been originally cannelured for a lighter slug.

I will have to do some more testing and get back to everyone.

Thanks again,
Bill.