.38 spl cases with a cannelure

I was always under the impression that the ones with the single line, towards the top were for regular bullets, and the ones with double lines, or more near the bottom were for factory flush seated wadcutters.

I have 45 colt, 45acp, 38spl, 357 mag all with the same thing.
 
Can I cannelure a pistol case?
Yes, short straight cases like the 9mm and 45 ACP can be cannelured to keep the bullet from shoving back into the case during feeding. A light cannelure is all it takes. (too deep a cannelure will shorten case life and is unnecessary).

Gentelman i hope this is of some help Thank You
 
I always thought it was a racing stripe

I always thought it was a racing stripe

Decorative, but serving no function. However, the notion 68fan voiced about it being there to prevent setback (or seating a bullet too deep) might have merit. Is there a narrowing of the diameter at that point on the inside of the case?

Lost Sheep (visiting his parents in Yuma, a far cry from Alaska....it's HOT)
 
Out of the thousands of .38 special cases that I have handled, I have seen hundreds of these cannelures. Many of them were so close to the case mouth that they would have been in the center of the bullet shank. Others were towards middle, end, doubles, so forth. Some of them were reeded, some of them were not reeded. If you look inside the case, you will find that there is only the tiniest protrusion, and they will probably not do squat for preventing bullet setback. In fact, if they could prevent bullet set back, why wouldn't Semiauto rounds have them?

There is absolutely no use for them. They are a decorative feature that may have had some actual purpose at some point, but they are decorative, and that is why they have been eliminated in modern ammunition.
 
You are all looking at the roll marks after they have been fired. In many cases, factory ammo will have the marks and they are quite deep. After firing, I imagine any mark is going to be ironed out by the pressure so there is no telling how deep it was on the unfired brass. On the other hand, they are also shallow on some factory ammo.

I have some recent manufacture Winchester .44 Mag that has the "roll mark" (for lack of a better term), but it isn't broken (dotted) like most. I would compare it to what the case would look like if you took a copper pipe cutter with a dulled blade and rolled it around the case. The indentation is deep, but it is too far below the base of the bullet to think it would prevent setback.

Another example is some .45 Colt that has a broken roll mark, and, again, it is deep.

On some .45 ACP Federal Hydra-shok I have, the roll mark is there, but it is faint and couldn't possibly create an indented ring inside the case like the above two examples. (This is "modern" ammo, so I guess it hasn't been eliminated entirely, brian.)

There may be more than one use for the markings. Setback prevention is a possibility, but as I, and others, have said, they are usually too far down the case to think that was the intention. If the roll mark is near the top, I can see how it would be a substitute for, or an extra added strength, crimp.

If the roll mark isn't indented at all, it may be an aid in the manufacturing process. Maybe each case is spun to check for run-out. Who knows?
 
Mal,

I've purchased many hundreds of new rounds of .38 with those "cannelures."

I've found them on target .38s with no crimp and on +Ps with tons of crimp and in rounds with both lead and jacketed ammo.

Rarely are they in a position to do anything positive about bullet setback.

"If they are shot out of a lever action rifle (with a tubular magazine) then you need to worry about bullet setback."

Sorry, I don't buy that, either. I've yet to fire any .38/.357 ammunition out of a lever gun that generates anything nearly enough recoil to make bullet setback a worry.

And, I've been seeing those marks on cases since the middle 1970s, when I first started buying ammo.

At that time lever action rifles in .38/.357 were pretty much nonexistent.
 
Mike said:
Mal,

I've purchased many hundreds of new rounds of .38 with those "cannelures."
...
Rarely are they in a position to do anything positive about bullet setback.
Click to expand...

Agreed, and that's why I said, "Setback prevention is a possibility, but as I, and others, have said, they are usually too far down the case to think that was the intention" among other statements negating the setback theory.

There is a reason for the rings, we just haven't discovered it yet. No manufacturer in their right mind would include an extra process in the manufacture of their cases if it was unnecessary. I seriously doubt it is a "decoration".
 
shooters love their gimmicks and gadgets. These marked cases differentiated themselves from the others visually. With some of the people I've known, that little ring, or a dab of red primer seal, or even a black coated bullet will make the thing more appealing, and more valuable.

It took a single operation to roll engrave those things into a case, and it may have even been done during another operation. It couldn't have added even the slightest bit of real cost to the shell, but I'm of the opinon that it added intangible value to the entire company's line, by making that individual cartridge look better, and more high tech.
 
Another vote for "racing stripe"?

briandg said:
...shooters love their gimmicks and gadgets. These marked cases differentiated themselves from the others visually. With some of the people I've known, that little ring, or a dab of red primer seal, or even a black coated bullet will make the thing more appealing"...
Click to expand...

Lost Sheep
 
shooters love their gimmicks and gadgets. These marked cases differentiated themselves from the others visually. With some of the people I've known, that little ring, or a dab of red primer seal, or even a black coated bullet will make the thing more appealing, and more valuable.
Click to expand...

I don't see this as a possibility either on account of the inconsistency of placement. I have boxes of factory ammo with these rings in different places on rounds from the same box.

I think this is why it's so strange. If these marks were in roughly the same place, we could surmise that whatever purpose it serves is the same on every round. However, that's not the case.

This is really funny though. I love threads like this. Somebody asks about something that I've wondered about as well, I expect it to be answered quickly by someone in the know, then it stumps everyone.
 
A .45-70 is quite the different critter.

It has markedly more recoil than a .38 or .357.

As others have noted, bullets moving FORWARD is often more of a problem with cartridges traditionally chambered for revolvers than bullet setback.
 
I was told the rings are there as a means of identifying different loads. But as was noted, if they are different in a box of new rounds that theory is out the window. I have seen these on many caliber cases. None of them was ever deep enough to have any effect on setback
 
I think this is why it's so strange. If these marks were in roughly the same place, we could surmise that whatever purpose it serves is the same on every round. However, that's not the case.
Click to expand...

I don't see this as a possibility either on account of the inconsistency of placement. I have boxes of factory ammo with these rings in different places on rounds from the same box.
Click to expand...

I'm not sure I understand your point there.

What you are saying just supported the "decoration" theory, in that what probably happened is two different lots of brass got mixed on the production lines. If there was a genuine need for the roll marks, that brass would have been separated by SKU number, and never mixed.

If there was a genuine purpose for it, other than decoration, I don't believe that the inconsistency of placement would be so common.

I'd also like to toss in that these are loaded at a factory, and the machines are (were) set up by men and micrometers, so they certainly aren't used as reference points for loading, like "powder to here, bullet to here..."

If there was a genuine purpose, they would be more consistent in location and usage, and most importantly, the manufacturers themselves would be touting them in their advertising as being important, and giving their reasons for using them.

"look, our brand has roll marks on the cases, which the other guys don't, so our ammo is better because**** and theirs isn't."
 
I was told the rings are there as a means of identifying different loads. But as was noted, if they are different in a box of new rounds that theory is out the window.
Click to expand...

That is the most logical answer yet, but still flawed. Manufacturing wouldn't need them, as those things are run in lots of millions of cartridges, and barreled and packaged as lots, rather than like a beer bottler who just has to change pumps, flush his system, and change labels if he changes from IPA to lager. If they were for end user identification a consistent system would be in use, like the military has.

It isn't entirely wrong, though, because a roll marked case could be easily picked out among a selection of standard hollow points, for example.
 
"If they are shot out of a lever action rifle (with a tubular magazine) then you need to worry about bullet setback."

Sorry, I don't buy that, either. I've yet to fire any .38/.357 ammunition out of a lever gun that generates anything nearly enough recoil to make bullet setback a worry.
Click to expand...

Sorry, my personal experience is different. With a tube full of 10 rounds, you now have more than 10X the bullet weight, plus the magazine spring pressure, even with negligible felt recoil. I have seen it happen myself. A gentleman at a match was experiencing audibly different report between shots in his rifle. He emptied the magazine, and there it was, some of the rounds were set back, others not. Those that were set back were visibly not crimped as much as those that were not.

Whether the case cannelure is there for that reason remains to be seen, but I was responding to a statement that we don't need to worry about setback in 38/357 cartridges. My experience refutes that, and I don't want anyone to think that it cannot happen to them.

Andy
 
For 45 long colt, and 45-70 I was told that the rings are there for reloading.
The lines give the proper depth for black powder.
45/70, Instead of having to measure every load. To get the 70 gr of black powder you fill the case to the line and seat a paper patched bullet. I actually measured this once and it came out to be very close to 70 GR. I have no idea what the normal load was for BP in Long colt to prove that it’s possible.
I don’t know if the first 38's that came out were black powder or not.
But the ring around the 45/70 and LC are different than what is on the photos. One possibility could be to add strength to the case. A vertical line added to a curved structure does add strength.
It could also be as simple as they have been doing it for so long with tooling that is also very old, why fix something that’s not broken.
 
Came upon this old thread doing a search for the explanation of those little rings on several batches of .38 and ,357 brass in my bench. At first I was amused by all the guesses as to what they were for, then I found myself disappointed that no one really knew what those suckers were for!
I agree that some of the rings are way too far down to be an internal stop for bullet seating. We have seen them all over the place; single rings, double rings, serrated and solid rings - surely someone knows why the manufacturers went to the trouble and expense of putting these in and in so many different locations. Damn!
The reason I even searched in the first place, is while I was sorting these out, it kept going around in my head that somewhere in my murky past I had read that these rings were there to identify the pressure that the case was rated at. What? :confused:
Well, that's why I did the search, to dispel that ugly tale with the truth. But it seems the answer may be buried in the X-Files somewhere: ("The Truth is Out There.")
Anyway, if somewhere on this forum the real reason (or best -sounding theory) has been expressed, someone please direct me. :D
 
You must log in or register to reply here.
Back
Top