quote:

Originally posted by D Humbarger:
BTW the bullets he was using were 130 accubonds & AA Mag Pro powder. Also that's a Hart barrel

I think it is correct to say that 'that WAS a Hart barrel'....Lucky his face was not blown off!

quote:

Originally posted by Bobster:
I'm inclined to accept the "flash over" theory. A reduced load of hard-to-ignite powder lies spread out along the side of the case. Then the primer flash passes over the top of the powder rather than through it. The pressure from the primer detonation pushes the bullet into the barrel to some point; creating an obstruction. There is a delay in the ignition of the powder and it begins to burn, creating an overpressure event.

But if got a 270 Win with 55 grains of 4831 and a 110 grain bullet seated hard into rifling and fired it you would get a very low pressure load.

quote:

The M700 action is plenty strong, but when you bore out the chamber paper thin, it is an accident waiting to happen IMHO.

It just seems like it is being "hot-rodded" with these super-fat magnums and over-stressing the design.

Wby barrel/thread is same as Rem 700 and 378 based calibres are bigger diameters than WSMs. Surely there has been a lot of hot rodding of the 30-378.

Here's a prophylactic method of being sure that this incident is not repeated:

USE.FACTORY.LOADS.

I am going to take a stab and say it was the barrel that let go at normal pressures.

Stainless barrels have a history of doing this.

quote:

Originally posted by wildcat junkie:

I always throw the charge from the measure into a clear plastic prescription bottle, dump that onto the digital scale tray, check the weight & trickle if needed, then dump the charge directly from the tray into the case filler funnel. I then seat a bullet before throwing the next charge.

I do it close to the same way, no powder throw for me even though I have one. on rifles (I don't even load handguns now) I pour into a glass bottle (smaller than a RX bottle) and then onto the scale, adjust it as needed, straight from the scale to the funnel into the case. every few rounds I recheck the scale to make sure it's still zeroed.

yes, I am slow.

Red

quote:

Originally posted by mauser93:
Here's a prophylactic method of being sure that this incident is not repeated:

USE.FACTORY.LOADS.

The Sakos that blew up were with factory ammo.

quote:

I'm inclined to accept the "flash over" theory. A reduced load of hard-to-ignite powder lies spread out along the side of the case. Then the primer flash passes over the top of the powder rather than through it. The pressure from the primer detonation pushes the bullet into the barrel to some point; creating an obstruction. There is a delay in the ignition of the powder and it begins to burn, creating an overpressure event.

I also subscribe to this theory but maybe with a twist. I have experienced hangfires, both pronounced and just perceptible, when loading cast bullets in my 404 with lower charges of slow powder and have also experienced this phenomena when working up loads for a 10.75x63 bolt action and a 10.75x47G double using jacketed 44 cal bullets swaged to 10.75cal. Again these latter two were with low starting charges of powder.

My 404 has a lot of freebore and with my very accurate load of AR2209 (H4350) powder I need a wool wad seated on top otherwise without a wad, I get a very slightly perceptible Kboom. With a wad, no problems at all, just a straight Boom. Von Gruff who also posts here uses the same identical bullet and powder charge as I do (it was his worked up load) but no wad in his 404 which he has chambered with very minimal leade into the throat.

In some ways this bears out the theory that perhaps the bullet is being forced into the rifling by flash over primer pressure (the K) before the powder charge is ignited (the Boom) which when it is there is then essentially a bore obstruction condition.

Maybe due to the less resistance of cast bullets there may not have been any cases of "detonation" reported where low charges of slow powder have been used when loading cast?

The twist to my theory is that apart from the physical condition of primer ignition induced bullet movement into the bore, the initial flash over of the primer may also serve to remove the burning rate protective coating on some or all of the powder spread along the length of the case and hence when the powder does ignite, we have essentially a very fast burning powder behind a bore obstruction, creating what we call for want of something else, "detonation".

It seems impossible that the same powder with intact burn rate coating will react differently just due to low charges. I think it is a combination of the factors I have outlined above, coming together to create the physical and chemical conditions for detonation.

Forgot to add that neck tension and crimp may also have some bearing on creating detonation conditions.

Would it be safe to presume that those 3 pics were a re-creation of the destruction as there is no blood or finger on the bench?

that not a shooting bench is the photos. Thats the tail gate of my truck. He had the accident the week prior & brought the gun over to show me.

quote:

Originally posted by D Humbarger:
A long time friend of mine accidently dropped a underloaded charge of a slow burning powder into a 270win short mag. Sierra told him the load had to be below the book minimum for this to occure. first 2 shots went inside a 1/2".
The 3rd & the one that wrecked the gun hit 1" from the other two. The barrel landed about 15 feet down range. The scope parts allover the damn place. All he lost was the index finger
on his left hand. He was lucky

failure

The picture of the exploded case reveals that the neck and shoulder are pushed into the case. This suggests that the chamber let go first and back pressure from the barrel blew the case in. I suspect the bullet did act as a bore obstruction a short ways in front of the chamber. The bullet began to move during the over-pressure event and exited the barrel just after chamber rupture, but before the barrel moved. This would account for the on-target performance and destruction of the rifle.

Did your friend have the luck to have a surgeon sew his finger back into place?

If I knew how, (I already use Photobucket, but would have to join Shutterfly) I'd download those pics, enlarge them, print them and hang on the wall of my reload bench as a constant reminder not to take anything for granted.

quote:

Originally posted by Doc:
truly remarkable. hence, this is why I take a flashlight after powder charging to assess uniformity visually, and also why I weigh each charge to this day.

Me too Doc!

too much damage. The doc said he could save it but it would be for looks only. It would never work again & Probably be more of a nucience. So they took the rest of it down to the thumb.

Odd things happen. I haven't experienced anything like this, or been around it either. LUCKY FOR ME. I have seen several rifles and pistols blown apart with double/overcharges, but nothing like this. Sorry for your friends hand,and his rig!

The Blue dot blown up rifle, had to have a plugged barrel, or something, LOL!! for Hot Core!

Jerry

quote:

Originally posted by Doc:
truly remarkable. hence, this is why I take a flashlight after powder charging to assess uniformity visually, and also why I weigh each charge to this day.

quote:

Originally posted by Bobster:
Based on those photos, it looks like Remington needs to make a large ring 700 to handle those short mags. There can't be more than an 1/8 th of steel around the chamber.

quote:

Originally posted by ar corey:

quote:

Originally posted by Bobster:
Based on those photos, it looks like Remington needs to make a large ring 700 to handle those short mags. There can't be more than an 1/8 th of steel around the chamber.

Help me out here....how much larger in diameter is a short mag case than a normal magnum case?

quote:

Originally posted by vapodog:


Help me out here....how much larger in diameter is a short mag case than a normal magnum case?

Belted is about .512 in front of the belt and WSM and RUM are about .550" on the solid head, a little bigger than the 404 Jeffery.

However, 378 Wby calibres are about .58 in front of the belt and the Mark V has the same barrel thread as Rem 700 although the threaded section is much shorter. There must of have been a lot of 30-378 loads shot since it became a facry round in 1998 and also available in the lower price Mark V Synthetic.

quote:

Originally posted by eagle27:

The twist to my theory is that apart from the physical condition of primer ignition induced bullet movement into the bore, the initial flash over of the primer may also serve to remove the burning rate protective coating on some or all of the powder spread along the length of the case and hence when the powder does ignite, we have essentially a very fast burning powder behind a bore obstruction, creating what we call for want of something else, "detonation".

If this issue of reduced loads of slow powders is factual then your explanation, at least in principle, would be a possible answer.

quote:

Belted is about .512 in front of the belt and WSM and RUM are about .550" on the solid head, a little bigger than the 404 Jeffery.

However, 378 Wby calibres are about .58 in front of the belt and the Mark V has the same barrel thread as Rem 700 although the threaded section is much shorter. There must of have been a lot of 30-378 loads shot since it became a facry round in 1998 and also available in the lower price Mark V Synthetic.

precisely.....and .020 on a side isn't the culprit here. If it were we'd have seen a lot of WSMs and RUMs blown to smitherenes.....

I'd wager this load would have taken this action apart if it was 1/8" thicker.....

There have been experiments that lodged a .308 cal 180 grain bullet in the barrel and blown out by firing another 180 behind it.....as hard as this is to believe it's an actual test done by (IIRC) Weatherby.....and IMO the Rem 700 is superior to the Wby MarkV!

quote:

Originally posted by Hot Core:
And here is another disaster caused by the same thing and this was a seafire "recommended"(aka Guessed At) Blue Dot Load.

Hot Core, Please, PLEASE, get your facts straight before maligning another member of this forum. It is true that seafire has kindly put together some Blue Dot loads for the use of forum members, but that does not make him guilty for the results of other people's unfortunate mistakes. The original poster in that thread admitted in the first sentence of his first post that it was a double charge; moreover, he did not even mention seafire in any of his posts in that thread (I just checked it). To take an example like this and say that seafire recommended it is completely unwarranted. It seems to me you owe seafire an apology.

I agree with Davis above. In fact, it might appear that Hot Core has some kind of personal agenda here......



.

I re-read this and looked it more, I think the real question is:

would this have happened to a mauser?

With the web of the cartridge unsupported, as they are in most Mausers, you can only imagine how much worse this would/could have been.

Jerry

I know the man that this happed to he said that the brass was once fired nickel that was given to him and that it had crud in it. He showed his freind. The freind pulled his reloads and found cobwebs in the bottom of the case.