I had my Redfield scope rebuilt and I mounted it and bore sighted it on my Ruger M77 270 win. I was sighting it in when the Seventh round I fired blew powder back in my face and smoke came out the trap door magazine. I was using a led sled and hearing protection. I didn't notice any difference in recoil and with my hearing protection I couldn't hear any different sound. I couldn't open the bolt or move the safety. I called a friend that knows about guns. we disassembled the gun removed the trigger,safety. We still couldn't move the bolt. He called a friend that shoots competitively and builds rifles. He told us what was wrong and that the ammo was probably an overloaded or wrong powder. We removed the scope, put the barrel in the vise, used a rubber mallet to force the bolt up to the open position then put a rod down the barrel and used the mallet to hammer the bolt and brass cartridge out. The brass cartridge had blown off the shoulder and neck. It looked like a straight wall cartridge. The primer was gone and the primer pocket was enlarged. The base of the cartridge was deformed. The barrel was clear no obstruction's. The bolt was covered with black soot. We cleaned everything and tried one of the empty casings to try the bolt action and everything worked fine. We looked inside the chamber and didn't see any problems. I called the manufacturer Barnes Bullets and they are sending me a email questionnaire to fill out and they would obviously like the remainder of the bullets back so they can test them. Anyone else ever have something like this happen to them?

How did the primers look on the first six? Any signs of excess pressure? I don't think it is possible to double charge a 270 but I am not an expert.

Nope , and I hope I never do.

Scary stuff.

all the other six looked and shot nrmal

No bulge in the barrel from a bullet being stuck? I guess anything is possible but like I said, I don't think a 270 has the case capacity to hold a double charge but maybe I am wrong. Had that been fired in an auto the outcome would probably have been a lot worse.

Its rare but sometimes factory ammo causes a problem. I bet barnes makes it right. They will likely want the unfired ammo. Maybe the rifle.

Do you remember if the bolt closed normally or was there some resistance?
And did you check the head stamp on the case?

Glad you didn't get hurt! That could of been serious.

I was shooting a few factory loads in my 308 and had a case crack about an 1/8 inch ahead of the rim. Also happened 3 times in one of my 222. All factory loads had powder charge come out of the back of the bolt. More reason to reload

No bulge in the in the barrel

They want the rest of the box , lot number and sku number and any shot cartridges. They haven't said anything about the rifle. I was just able to make contact with them yesterday.

I don't remember any resistance while closing the bolt. I didn't check the head spacing. I've had the rifle for 40 years. my wife bought it for me ,new not used. I shoot it maybe three to ten shots a year and clean it after hunting season which is two weeks long. I clean it with Hopes 9 solvent and use gun oil to lubricate it for storage. I have never had any problem with this rifle. In 1991 I was shooting Winchester ammo that had five missfire and it was the ammo problem not the gun as I had it checked by a gunsmith.

Certainly looks ammo related.

Also, there are better barrel cleaning products on the market. Hoppes 9 won't remove any copper build up.

Make sure the chamber is clean of all dirt,and possibly rust.
A dirty chamber makes excessive pressure

Just remembered something similar happened to my buddy’s wife but worse. Her 22-250 basically blow apart. She was prone shooting prairie dogs and the back of the bolt blew out of the back of the rifle (Remington 700) the bottom of the stock exploded the gun was destroyed. Remington ammo. They wanted the rifle and the ammo that was left. They actually gave her a different rifle in the end. She very lucky she didn’t get hurt.

My rifle is very clean and no rust anywhere and the trigger assembly is clean and lubricated . No rust anywhere.

I've only used copper ammo for a few years now (Barnes-Only) and shot less than 60 rounds of it through my rifle.

I know a shotgun barrel can bulge, but is it possible to bulge a rifle barrel and not have a catastrophic failure?

Bulges in barrels are caused by an obstruction in the barrel. I don't think that was the issue in this case.

I understand. I just didn't think you could bulge any rifle barrel because they're much heavier/thicker than a shotgun barrel. I've bulged a shotgun barrel, so I know it can happen with them.