Separate names with a comma.
Discussion in 'Long Range Hunting & Shooting' started by normyt, Sep 9, 2019.
But wouldn't the bullet have still be lodge in barrel?
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.
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?
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.
I had thought about oversized bullet at first as well.
So what do you think caused his rifle to explode like that?
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.
Maybe, maybe not. Bullet may have hit the ground 1 foot in front of you.
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.
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.
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.
Norm. l think the only chance of finding an answer about your gun is..
SEND IT BACK TO SAVAGE..
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.