Posting this for a friend but a lot of great minds here.
Remington 700 .270 Win stock rifle. Remington stock 270 win ammo (not reloads). Had been functioning fine and shot several rounds from the same box of ammo prior to this one (with stock accuracy as expected). This round detonated (misfire) and sprayed shooter with brass, powder and blowback (no major injuries thankfully). The bullet cleared the barrel (barrel clear) but locked the action up tight. Bolt removed (with great difficulty and breaking lever off) and this is what the case looked like after. Bolt neck fractured. The case primer pocket is 5x expanded. Dents in the case neck occurred while removing case from action. Any thoughts?
Is there any bulge in the barrel that could indicate an obstruction ?
Sounds like no because of the previous ok shots.
Do you have any enemies ?
Did you lay the gun down by sliding it muzzle first where it could have picked up an obstruction just before that shot ?
Check the bore out for any signs of heavily smeared copper in one spot . In this case it would have to be very close to the muzzle otherwise the barrel would have split .
Did your ammo ever be in a place unattended so that someone could have set you up with an overload ?
If the round was taken out of a new box of ammo it sounds like the powder load was the wrong type way too fast or spiked , maybe an act of vandalism by some disgruntled employee.
Don't shoot anymore of the box or batch that it came from.
If there is no indication of any fault on your part then report it to the manufacturers and go from there .
There is another possibility and that is a faulty weak case head that just gave up .
From what you have said it sure looks like faulty and or way over pressure ammo .
Location: SOCIALIST CONTROLLED TERRITORY OF NEW YORK
Re: What the heck happened here...???
Is the bore clear? Looks like you had an obstructed bore and the rem action did its job and held together. Glad you were not hurt. Save everything! unfired ammo, brass do not touch the rifle. Contact ammo manufacture and Remington.
See that is what you get for shooting factory ammo. Partly kidding. The only ammo mishaps I have ever had was with factory ammo. Keep that box the ammo came in and call the company RIGHT NOW so they can get that lot # recalled and pay for your rifle. Call Remington and tell them the facts. Thank God you were shooting a Remington 700 because of it's strength.
The barrel looks to be intact no bulge, no obstruction. An obstructed barrel would cause a very different explosion and would not explain why the base of the case blew out. It was a remington stock gun with factory remington ammo. The gun was shooting off the bench at a range and previous shots were fine and the round immediately preceding went bang with no hint of problems. Everything is going back to remington. I agree that the problem seems to be with this single round (wrong powder, spiked). I just wanted to see if anyone had an issue like this before or could at least tell me what exactly happened according to the laws of pressure.
On another note, I had the polymer tips falling off a box of winchester 7mm silvertips. Unexplained flyers were suddenly explained. Never shot factory ammo again. Likely never will again.