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BCB
02-28-2016, 02:07 PM
A 445 Super Magnum shot in a Contender…

I have fired hundreds of rounds through this barrel and have never had the problem shown in the picture included…

The case split almost exactly in the middle. The front part stayed in the chamber but I was able to get it out with a hook I bent on a piece of wire…

The load was only 9.0 grains of TiteGroup with a 429650 that was seated within a hundredth of an inch of the rifling and I have shot it before—no pressure signs at all…

Actually, the primer can partially be seen in the picture…

Did the case just fatigue and finally let go? They have been reloaded at least ½ dozen times and it is a Starline casing…

The group is what it shot at 50 yards…

Any thoughts?...

Der Gebirgsjager
02-28-2016, 02:19 PM
Yup..my guess would be that it just got tired. How does the other brass look when examined with a magnifying glass? Did it separate at a cannelure in the case? Over the half-dozen loadings of the case's life where hotter loads used? Possibly just this one case is an early failure, but I'd keep an eye on the remaining cases of the same batch and inspect them closely before each reloading.

Wayne Smith
02-28-2016, 05:42 PM
As the German guy above said!

BCB
02-28-2016, 06:05 PM
Yup..my guess would be that it just got tired. How does the other brass look when examined with a magnifying glass? Did it separate at a cannelure in the case? Over the half-dozen loadings of the case's life where hotter loads used? Possibly just this one case is an early failure, but I'd keep an eye on the remaining cases of the same batch and inspect them closely before each reloading.

It didn't separate at a cannelure...

Some of the brass may have been loaded warm when I first got the barrel, but not much more and then only a time as I simply didn't enjoy the recoil. It is vicious with a hefty charge of H-110...

I am hoping it was just an isolated case also...

Guess I'll take my wire hook with me to my shooting range the next time just in case more decide to let go...

Even though the case failed, the 50-yard group isn't all that bad...

Thanks...BCB

BK7saum
02-28-2016, 11:29 PM
Instead of a wire hook, try a bore brush. Run it into the chamber and pull backwards. I've removed a few separated cases that way.

Brad

Wayne Smith
02-29-2016, 03:15 PM
Save the hook to check the rest of your fired cases for internal creases. These will show where the next one will break.

BCB
02-29-2016, 03:47 PM
Save the hook to check the rest of your fired cases for internal creases. These will show where the next one will break.

That I have already done...

Didn't feel any grooves inside the cases I checked...

The unfired ones will test themselves...

BCB
03-09-2016, 09:00 AM
Several more cases. I am now beginning to wonder if this is actual case fatigue...

Maybe an ever-so-slight defect in the chamber allowing the brass to minimally weaken at the same location each time it is fired?...

Bearbait in NM
03-09-2016, 02:48 PM
BCB,

If you do a google on "incipient case head separation" you will find this issue with bottleneck rifle cases. It is an issue with excessive headspace. It happens when the front part of the case grips the cylinder wall hard at ignition, pressed hard into the neck portion of the chamber, and the back "half" of the case gets thrust against the breech. The brass stretches and weakens at this juncture. I have never seen this with straight wall cases, but most certainly have with bottleneck cases.

But, your first picture shows some interesting scratches or rings on the surface of the brass. Is it possible that there is some roughness or irregularity in the front portion of your cylinder that is "gripping" the case at ignition? Perhaps this happens after the chamber gets dirty? Just grasping here, but as your case looks like a case head separation, perhaps the finger points to a similar mechanism?

Craig

M-Tecs
03-09-2016, 02:58 PM
It may be a headspace issue. If it is you can shim http://www.bellmtcs.com/store/item.php?pid=1022&cid=290 or seat your bullets out far enough that you have to snap the action closed.
http://bulletin.accurateshooter.com/2013/01/case-head-separation-causes-and-how-to-spot-problems/

BCB
03-09-2016, 03:42 PM
Yep, I'm familiar with headspace separation with bottleneck cases--been there and done that!!!...

Of all the straight walled cases I reload for, I have never had this happen to any of them...

This may remain a mystery...

Thanks...BCB

M-Tecs
03-09-2016, 03:57 PM
Headspace can be an issue with all cartridges. Separations with bottleneck cases are the most common but it can happen with straight wall cases also. Higher pressure straight walled cases have much more of an issue than low pressure cases. I don't know if its possible to get a lower pressure round like the 45 ACP to head separate. My first 45 Colt Contender would do it with warm loads unless I jammed the bullet into the rifling.

I love Contenders but headspace with them can be an issue.

Good info here. http://www.lasc.us/bellmHeadspace.htm

BCB
03-10-2016, 04:01 PM
Headspace may be the problem, but I also find that hard to accept with a straight wall case. It headspaces on the rim, although I suppose the depth of the place the rim sets could be too deep…

This 445 SM was a 44 Magnum in the beginning and I had Bellm chamber it to 445SM. Since he writes much on headspace and his tools to adjust or determine that, I would be quite disappointed that his rechamber would not be of correct headspace. After all, the straight wall case would only have a problem with the rim thickness. And since the 44 Magnum and the 445 SM have rim thickness of 0.06” there should be no problem—Unless the barrel was made incorrectly from T/C. Although I never had problems with the 44 Magnum splitting cases. Yet, I got the chamber redone to 445 SM because the accuracy for the 44 Magnum was 5”+ at 100 yards with the barrel ‘scoped. Absolutely terrible accuracy…

The pics I show of the cases being split are interesting. The length of the case from the rim to the split of both cases is within 0.002”. That is amazing for a case failure. I still think it has something to do with the chamber at the area the case separates…

The barrel has been a problem from day one in that it had no accuracy when it was a 44 Magnum. Accuracy improved some when rechambered to 445 SM but now the cases separating is a problem. These cases have been fired with “warm” loads, but never maximum. I am now shooting 10 grains of TiteGroup and the 429650 which produces around 30K pressure—not at the upper end of the 445 SM…

Don’t really know, but I do know that getting rid of this barrel might not be too much of a problem for me!!!...

Thanks all…BCB

Joni Lynn
03-10-2016, 04:16 PM
Just to satisfy curiosity can you show a close up photo of the side of the action on your gun? I'm not trying to waste your time, I have a reason to ask.

BCB
03-10-2016, 05:07 PM
This what you were looking for?...

Joni Lynn
03-10-2016, 05:11 PM
Yes, thanks. Where the horizontal meets the vertical of the breech if there is a small wavy area in what some call the elbow area it indicates frame stretch and means that frame is done. Hopefully the other side is perfectly smooth as well.

rking22
03-10-2016, 05:52 PM
I have had 44mags seperate exactly the same way in my Browning M92. Most likely headspace issue, hopefully not the frame "springing"! Those cases that seperated should have shown an inner "ring" that could be felt with a sharpened hook and a wire. Check your other cases, especially if any were fired in another gun that may have had headspace issues. Also may be a rough area in the chamber holding onto the front while the rear stretches to takeup any normal headspace. Sure can be a bear to get out of the chamber when they seperate like that!

Bearbait in NM
03-11-2016, 01:43 PM
BCB,

Just to add more confusion on top of the already discussed headspace possibility, now that you noted TG. When working with Tightgroup in my 454, for the top side of low end loads using lead, I found that I would get cases sticking, on ejection. These were clearly not 65k pressure loads as would be excessive in my FA 454. They should have been around the 25-30K mark. Max book charges for this fast powder. Something about the pressure and Tightgroup and maybe the alignment of the sun or moon was causing them to stick. If the front of the case was sticking, would the back part rebound back and possibly behave like the bottleneck situation?

As I posted above, and others have noted, if the front of the chamber is grabbing the case, this might happen. If you have this situation, and you are getting behavior with Tightgroup like I was seeing, perhaps a compound situation? The hard way to check this might be to remove the extractor from the TC. Fire a round, and punch the case from the chamber. Compare the resistance felt against loads with other powders. Or compare the growth to the OAL of the fired cases with this load to another powder load?

Craig

BCB
03-12-2016, 08:46 AM
Well, I shot 15 rounds yesterday with not a separation…

I tumble those cartridges and observed them well before I will reload them again—I don’t see any signs of pre-separation (is that a word!!!) and the inside doesn’t seem to have the start of separation when I use a bent paper clip to check that…

These reloads can be loaded to touch the rifling as the 429650 is certainly long enough. So, the case head is tight against the face of the receiver…

I did check Hodgdon data for the 44 Magnum and a 320 grain boolit and it says 9.2 grains of TG is maximum. I am only shooting 10 grains in the 445 SM so that shouldn’t be a radical load. Extraction is easy. The extractor moves the case about 1/4 inch when the barrel is opened and the case is easily removed with my fingernail...

I’ve used the same frame for the 30-30 Winchester and the 7-30 Waters with no problems at all. Some of the 30-30 Winchester cases have literally been loaded nearly 20 times. I do headspace these rimmed cases on the shoulder and the boolits touch the rifling—not much room for anything to move when the primer is struck…

So, I’ll fire the rounds I am going reload this morning and see what might be again…

Then, I think I will get a dozen new pieces of brass and shoot them and keep accurate records of how many times they have been fired…

Still, I am a bit amazed at how precisely these cases separate at the same location…

More to come—maybe…

Thanks all…BCB

BCB
03-13-2016, 01:22 PM
Went to my range yesterday and finished shooting a box, ~20 rounds, of the 445 SM…

Accuracy is around 1.5” to 2.0” at 100 yards, but occasionally that goes haywire also—in the lousy direction…

One case completely separated, and 2 cases had visibly defined rings at the location the separation would likely occur the next firing…

Packed up the fired rounds and the Contender and went home. Place the rounds in a Ziploc bag with a note included and placed it in the section of my shelves for 44 caliber ammo—NO MORE 445 Super Magnum and the Super 14” for me. The barrel was a problem when it was a 44 Magnum and it is a problem now that it is a 445 Super Magnum—‘nuff said…

Oh by the way, the pic included is the round I was shooting today from the same Contender frame. The good ol’ well proven dirty-thirty cartridge. A 311041, CCI 250, 35± grains (thrown charges) of surplus WC-860 for a velocity of 1330 fps. (The wheel weight I found by the roadside!!!) The case has been annealed at least 2 times and maybe 3 times. When the expander plug starts to squeak, get out the torch. Put the case in a socket that is hooked to a variable speed drill, turn it with a propane flame on it, let it get cherry colored, and then dump it in water. Some will condemn getting it cherry red color, but hey, it works for me and always has…

I have groundhog-sized steel silhouettes at my shooting range. They are at 100, 150, 200, and 250 yards. With the know holdovers, I rattled each one 4 times. Started at 100 yards and worked out to 250 yards. Then reversed the order…

Didn’t really like the 445 Super Magnum anyhow!!!...

Thanks all…BCB