Why do some 45 Colt cases have rings?

[feets]

I've been looking at my Colt cases. All of these were purchased as loaded ammo. Why would the manufacturers put grooves around the cases? Was it simply to control bullet movement with the light charges used in these things? If that's the case, why aren't all of them set like that?

The two cases on the right are Remington. The two on the left are Winchester.

http://a1.sphotos.ak.fbcdn.net/hphotos-ak-ash4/392307_310664595619278_100000272212256_1222368_214 251807_n.jpg

I have other cases with grooves higher up.

Sorry, but it's been too long since I bought the ammo to know which loads they were.

[Dale53]

You have it correct - the cannelures are to prevent deep seating of bullets. For reloading, of course, most of us would prefer NO rings.

Dale53

[feets]

What's interesting is that some of those cases have the cannelure at a good height to set some of my long pointy bullets deep enough to keep them barely inside the cylinder.

Most of the ringed cases end up being used for plinking loads.

[220swiftfn]

Magtech Cowboy loads have the case cannelure too, I believe that they do it to prevent setback in a lever mag tube.......


Dan

[Mohillbilly]

Exactly my .45 winmag ammo has them too , and it is to control bullet set back .

[mpmarty]

The ones with rings are married or engaged?

[KYCaster]

I've been told it's to identify different loads at the factory. The same bullet shape, but different weight will have the cannelure in a different location or none at all, making it easy to identify the load by sight.

If it were there to prevent bullet set back, why don't they put it on all the cases?

Jerry

[MtGun44]

Almost certainly the cannelured cases would have been originally loaded with a cast
or swaged boolit without a crimp groove. For example, the swaged Rem and Win versions
of 454190 which has no crimp groove and slopes rapidly. They were originally kept from
pushing in too much be a full load of black powder under the boolit.

Bill

[41 mag fan]

The ones with rings are married or engaged?

Good question. They could of came from one of those same sex states.