What blew up my gun?

[normyt]

My guess would be a reduced load. The primer goes of and starts the bullet down the barrel, but the powder delays in igniting. When it does, the bullet has stopped and is now an obstruction in the barrel. The powder explodes and causes EXTREME pressures! Almost did that with my .223 years ago playing with reduced loads. Luckily it only destroyed the brass and blew gas out the vent hole.

But wouldn't the bullet have still be lodge in barrel?

 

[normyt]

i have not read through this entire thread, but have you pulled the bullets and checked the powder on the remaining handloads? I have seen varied failures from others, and while not always the case, we do find loads that were made with the wrong powders.

I pulled all remaining reloads from this batch (approx. 20)
Powder looked like powder in 1lb bottle (not powdered or anything)
Case length were all between 1.88" & 1.91" ( in spec.)
All cases had 34.6gn of Varget except 5had 35gn, 3 had 36gn & 1 had 37gn
I went back to Hornady Load Book and 34.6gn is absolute Max for 55Gn V-Max bullet
The loads I've been making are for 50Gn V-Max bullet. (which I used previously)
Max amount of Varget I could get in a 22-250 case is 39gn
Looks like I've been living on the edge for quite a while.

 

[normyt]

Looking back at my records.
I was originally reloading 35gn Varget & 50Gn Hornady V-Max bullet.
In Feb 2016 I bought a Scorpion Red Hot scope calibrated for 55Gn bullet.
So I started reloading with 35gn Varget with a 55Gn Hornady V-Max bullet.
This is over max load per Hornady Load Book (34.6gn for 55Gn bullet)
Once I got that scope sighted in I probably shot minimum 300-400 rounds.
As per my previous post my remaining reloads after incident varied from 34.6gn to 37gn
so I thinking maybe after that many overloads rifle may have developed some kind of metal fatigue until that one bullet.
Any thoughts on that theory?

 

[K1W1Spada]

I pulled all remaining reloads from this batch (approx. 20)
Powder looked like powder in 1lb bottle (not powdered or anything)
Case length were all between 1.88" & 1.91" ( in spec.)
All cases had 34.6gn of Varget except 5had 35gn, 3 had 36gn & 1 had 37gn
I went back to Hornady Load Book and 34.6gn is absolute Max for 55Gn V-Max bullet
The loads I've been making are for 50Gn V-Max bullet. (which I used previously)
Max amount of Varget I could get in a 22-250 case is 39gn
Looks like I've been living on the edge for quite a while.

So glad you were not seriously hurt.
From your last photos I think I can see evidence of stress fractures over time.
The split faces of the action should all be a single bright steel color if the failure occurred in one horrendous pressure event.
The pics seem to me to show very dark patches with brighter steel edges a sure sign of pre-existing stress fractures.
This could match up with your findings of higher than intended loads over time.

There has been much speculation on the exact cause with no definitive answer.

My suggestion (if you have the means) is to get the action assessed by a metallurgist, It may be showing signs of fatigue cracks (difficult to say exactly from the pics supplied but the suspicion is there)

If there were cracks developing It would have severely weakened the action.
Thus the pressure required to cause the failure would have been significantly less.

 

[jbs2014]

First off, I'm very pleased to know the OP wasn't injured. That is always a possibility in our sport and wearing the proper safety equipment always makes things even safer!

I very much doubt that any one of the suggestions (bullet weld, long case, bullet jam, case head seperation, etc.) would have caused such a catastrophic failure. To be honest, even a full charge of Varget wouldn't be quite that bad, either... at least for a few shots (although there should be indications, hard bolt lift, flattened out primers). Loading on the hot side (plus!) as a way of life? Clearly not so good for the rifle or brass! Actually, my first thought was an oversized bullet, although that should have been obvious and difficult to chamber.

I have had, at some point or another, each of the situations mentioned and never had much more than a blown primer or a bit of difficult bolt lift. Complete case head seperations weren't even noticed until just the case head ejected. Probably the worst mistake I've made while reloading was using the max data for a 210 gr. and loading a 250 gr. bullet in my .338 WM. That one set me back some and certainly got my attention! The entire primer was blown out of the case, although the case did extract ok. Them Ruger folks build a tough rifle! Figured that one out right quick and have been doubly cautious ever since!

I've had ammo that I couldn't get to release a bullet with an inertia puller (one did, finally but it took 20 minutes of smacking that hammer on the ground). There were misfires but no hot shots. I finally got smart and seated them a bit deeper first. Bullets were cold welded to the case. Long bullets, long cases, usually a bit of noticeable difference in recoil, enough to start me to checking, anyway.

While not impossible by any means, "powdering" a load of rifle powder is a whole lot harder than most people think. Back when I had my shop I used to tumble loaded ammo (especially lead pistol loads) in a large thumblers tumbler over a hot plate! I lubed the cases prior to loading, then tumbled them in clean corn cob grit to get the lube and bullet wax off... sometimes I'd leave it run overnight. Never had any problems with the powder (and yes, I pulled bullets to check).

If you stop and think about it, there are a lot of things that can go wrong rolling your own, enough that the lack of problems and injuries is a testament to the fact that our firearms are tough and generally speaking, we are all amazingly safe reloaders. Overall, I think we should all be proud of our safety record... and remember to double check everything to maintain that record.
Cheers,
crkckr

I had thought about oversized bullet at first as well.

So what do you think caused his rifle to explode like that?

 

[antelopedundee]

I've heard of use of hot loads over time stretching an action, but that would seem to make more sense if the lugs were in the rear but not up front altho a stretched action may not be dangerous. I'm inclined to speculate that the case was way undercharged. Would be interesting to get a beat up gun and try half loads with gun being fired from a horizontal, vertical and pointing down position.

 

[Barrelnut]

But wouldn't the bullet have still be lodge in barrel?

Maybe, maybe not. Bullet may have hit the ground 1 foot in front of you.

 

[MNbogboy]

As K1W1Spada mentioned in his post there may have been previous damage.
Having spent 20 years in heavy equipment failure repair and the next 30 in mechanical engineering including more failure analysis. Often photos were used showing obvious clues (ie; staining, crystalline abrasions etc). In this case the heavy soot may be hiding something or deceiving as to making any conclusive answer.
The photos do show that the sides of the bolt nose & extractor were blown completely off with the bolt in battery when the case ruptured. The brass that impaled itself inside of the receiver shows it was in correct position at the moment of impact.
My thought is that at that moment the receiver split allowing violent upward thrust of the bolt. (Imagine shooting the inside of the receiver at point blank with a steel & brass projectile at 22-250 velocities [or more].)
It would be interesting to enter all scenarios into a FEA program. If I wasn't retired I could do that but don't have the program and a computer big enough to run them anyway. It could show a step by step failure starting with the case head/web at xxx pressure.
The case and part of its rim left in the barrel also corresponds with the parts of the bolt nose left intact. Another reason why I believe the brass failure first preceded the rifle damage.
Imho,
Randy

 

[kiwikid]

After reading pages 151/152 of the Norma reloading manual I wonder if this may have been caused by lack of powder and what is sometimes referred to as a Detonation. Apparently this was proven by the Krupp Commission 1888 and although it is normally associated with magnum cartridges and slow burning powder I wonder if it could happen in a 22-250 with Varget powder. I would like to post the info here from the Norma manual but it is covered by copyright and is a whole page long. There is mention of this info in this link for those that wish to read it.
https://gunsmagazine.com/our-experts/handloading/true-confessions/

 

[woodsmanlw]

Looking back at my records.
I was originally reloading 35gn Varget & 50Gn Hornady V-Max bullet.

35gr Varget is my standard load for 55gr bullets but they are Nosler BT, so different bullet and different base but they should be comparable as the weight is by far the largest variable, followed by ogive shape, which affects distance to lands. The thing is, even if your rifle failed from stress fractures would a standard load do that kind of damage? Interesting possibility. I'm still leaning toward too little powder and detonation. You have an interesting situation that I wish you didn't have to arrive at it in such a dangerous and expensive fashion.

 

[sw282]

Norm. l think the only chance of finding an answer about your gun is..
SEND IT BACK TO SAVAGE..

 

[Barrelnut]

After reading pages 151/152 of the Norma reloading manual I wonder if this may have been caused by lack of powder and what is sometimes referred to as a Detonation. Apparently this was proven by the Krupp Commission 1888 and although it is normally associated with magnum cartridges and slow burning powder I wonder if it could happen in a 22-250 with Varget powder. I would like to post the info here from the Norma manual but it is covered by copyright and is a whole page long. There is mention of this info in this link for those that wish to read it.
https://gunsmagazine.com/our-experts/handloading/true-confessions/

Great read.

 

[Littlehud]

Understood, but car makers deliberately crash cars to see what happens in real world accidents, so I expect somewhere that gunmakers maybe have tried similar, tho I've never seen where a gun writer ever did an article about it. I can't claim to have read them all tho.

I had a room mate years ago that went to work for a gun manufacture in Utah. They built 45 win mag. pistols. They would put the equivalent of 5 times the max load, and put a solid barrel instead of a bored out barrel and fire it to see if the frame would hold up. It did some damage but the frame held.

 

[LongestShot]

I had a room mate years ago that went to work for a gun manufacture in Utah. They built 45 win mag. pistols. They would put the equivalent of 5 times the max load, and put a solid barrel instead of a bored out barrel and fire it to see if the frame would hold up. It did some damage but the frame held.

I'm amazed that they were able to get 5 times the normal amount of powder in the cartridge.