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I am not shooting the messenger or anyone else, I may have read his post incorrectly but don't think so some one screwed up on the reload. Rio7

I think you're right about that.

Just wonder what he did.

DF

The velocity makes it quite clear, that it was an overload.

Dusty,

Would you mind sharing the load for the 180 grain bullet loaded into a 30-378?

The Retumbo bottle lists a 180 grain bullet over 113 grains of Retumbo in the 30-378. My ballistics program indicates that the pressure is close to 70,000 PSI, but not quite there. It indicates that's a safe load.

I locked the bolt on an FN Mauser with an overcharge in my 6.5x55. I was able to open the bolt with some effort, the primer was blown.

We figured with QL that is was around 80K+ psi.

This sounds like a lot more presssure than that.

DF

One of the other posters on that board said his BP estimated the pressure at around 100,000 PSI.

Just some thoughts:

Light charge and S. E. E.

Last warm up load might of been a squib load, leaving a bullet in the barrel. I have seen this before.

Barrel obstruction. Snow, mud, ice. Maybe a cleaning rod left in the bore.

Wrong powder.

Overcharge

100,000psi? He is lucky the rifle did not turn into shrapnel.

Worst blow up I have seen was a Carcano. Shooting mil-surp ammo, bullets were pulled and replaced with long soft nose. Case mouths were loose. A live round was chambered, then ejected. The bullet stayed in the throat, not noticed. Next round chambered had another bullet ahead of it! Pieces of steel and stock splinters everywhere. The shooter was badly burned over the face.

He stated the velocity reading on the shot fired, so obviously not a obstructed barrel.

Several...dozen years ago I was visiting with a custom action manufacturer who just happened to pick Bryan, TX to open up shop. We talked about a lot of things, but I mainly listened. He told me he proofed his actions at 200,000 PSI. I think he said his proofing was among the highest, but, other manufacturers sometimes proofed theirs to 100,000 PSI. At the time I had already purchased a Hall G action. If I've ever seen an action that absolutely would not come apart it was that Hall G action. It might destroy the bolt and barrel, sending one down range and the other through the shooters head, but the main part of the action would survive a nuclear strike.

I had to vigorously "tap" the bolt handle on that Hall G action one time. I was shooting a 30-378 using 180 grains Nosler Partitions over a charge of IMR 7828. I'm not sure why I loaded those rounds with that load of 7828, but it obviously was way too much. That wrapped up the day. I took the other rounds home and pulled the bullets and reloaded them with a sane charge of H50BMG.

I met a reloader/shooter at Dr. Kenneth Knotts gun smith shop in Castor, Louisiana not long ago. His brother had blown up a rifle. They dismantled the rest of that batch of hand loads and found that someone (probably a kid) had come along and dropped primers in the already primed brass sometime between the priming and the powder addition. So much for leaving your half finished loads unattended. Here's hoping it wasn't a saboteur. I've never thought to try an extra primer.

Wow...

That would do it.

Those primers would be like a REAL fast burning powder, probably worse than having a pinch of Bullseye in there.

DF

DF's explanation seems the most logical to me.

Damn, he screwed up somewhere, don't believe it was the powder.

I use Retumbo in my 300 win mag under 230 gr Berger OTM's at 2850 fps, also use it to drive 300 gr 338 cal Accubonds to 3000 fps, both loads are extremely accurate, stable and dependable, have never had anything weird happen using that powder.

I think he put the powder charge he was using under the 190's into the case and put the Berger 230 on top of that.

This is what I think too.

Barrels have been known to split in extreme cold and this is why many barrel makers will not do pencil thin ones out of 416 stainless. I don't know if this would affect the action too possibly it could as the steel is less resilient in extreme cold.

It'd be like the second stage booster on a Saturn V rocket.

What troubles me is that they destroyed the action. Typically you remove the barrel, or at least wreck the barrel by parting
just in front of the action to the minor dia. of the threads. use a barrel vise and an action wrench on the outside of the action.
you should be able to at least see if you set the lugs back, then maybe just replace the bolt.

just saying...