Tell me what you think causes this.

[Aussie_bob]

Ok Guys will attach a pic of a .223 case the primer was blown out and it seemed to have a large flash hole what do YOU reckon would be the cause of the ridge on the case.

 

[Forum Boss]

Wow--a new belted mini-magnum.

Has to be extreme overpressure. If if wasn't a situation of the wrong powder, I'd guess a barrel obstruction,patch left in bore?) or some serious internal flaw in the case.

This does illustrate that in almost all bolt-action designs, there is an area of the case that is unsupported.

 

[KHGS]

Bob, what brand of case, what powder & what was the bullet weight?
What rifle was it? looks like a fair bit of unsupported case in the chamber.
Keith H.

 

[Cochran]

The first Winchester Heavy Varmints, before the recall, had excess unsupported case and would do that or worse. I know from experiance.

Jeff

 

[Aussie_bob]

Well i was assured it was brand new Lapua Brass and this was its first fireing. Some of the other cases were also showing signs of doing the same thing.
This particular old bloke is a pain in the preverbial forever haveing problems and will not listen i believe he has headspace problems as well as over charged. Different people have offered to help him but he knows best.
The action is an Omark and has a conversion piece fitted, Keith you would have seen these, LLoyd Neilson from up here made them i do not know much about it i would have liked to get one of the other cases and knocked the primer out as the one in the photo had blown the primer and it had a very large flash hole.
Wouldn`t let me have a case thats why i took the photos.
Will attach the one of the flash hole you may be able to see it.

 

[Aussie_bob]

Didn`t take the attachment so will try again here.

 

[KHGS]

Bob, I would be suspicious of the integrity of the barrel fit. I have seen this very thing many times with Omark's & adapters, the rash of "back-yard" barrel fitters we have in OZ can't seem to get their heads around the more complex turning required to fit barrels to Omarks,with adapters) & have them feed .223 cartridges successfully. One of the very reasons why I am reluctant to supply blank barrels to customers without being sure of who will ultimatly fit them.
Keith H.

 

[Aussie_bob]

Well that is exactly what we have told him that he needs to get it seen to i have a sneaking suspicion that he bought the rifle with a couple of barrels and has just screwed this one on by himself.He may be sending it to Brisbane to be looked at with the brass at least i hope he is.

 

[AckleymanII]

There is no doubt that you have a problem with the chamber on this rifle. It appears that there is a step in the chamber that is the equal of a belted magnum. As the case head swells to fill out the larger section in the barrel, the primer pocket swells out as well.

DO NOT FIRE THIS GUN AGAIN UNTIL YOU HAVE HAD A GUNSMITH REMOVE THE BARREL AND CHECK IT. You can take a chamber cast and check it yourself.

Best wishes and good luck!

 

[RAVEN]

Aussie_bob
I hope this person is not shooting next to anyone that rifle is unsafe and the person should not be allow to fire it until the problem has been rectified by a competent G/Smith
now there's a job for U KH

 

[USAPatriot]

There is no doubt that you have a problem with the chamber on this rifle. It appears that there is a step in the chamber that is the equal of a belted magnum. As the case head swells to fill out the larger section in the barrel, the primer pocket swells out as well.

DO NOT FIRE THIS GUN AGAIN UNTIL YOU HAVE HAD A GUNSMITH REMOVE THE BARREL AND CHECK IT. You can take a chamber cast and check it yourself.

Best wishes and good luck!

That's my thought as well. Headspacing? I don't see how. If it was long enough to cause that bulge the bolt wouldn't close. It almost looks like chambering was started with a larger reamer, the error discovered, the proper chambering accomplished but the bad section was never cut out. Depending on the gun and the size of his pinkie finger, he may be able to get the finger up in there and actually feel enough of the chamber to confirm it's cut wrong. -Rod-

 

[Aussie_bob]

Don`t worry once it was noticed, he was told to pack it up and don`t bring it back till its fixed.
I know if he brings it to a shoot i am running i will want proof its been fixed.