What blew up my gun?

[antelopedundee]

I think you might have found it. My scale drifted a lot (.8 gr) without my knowing it. I sent it back for recalibration, but I check and verify with a beam scale and trickle if too light, nowadays.
My 22-250 is running just below max for my manual, at 35.6 gr. of Varget and running 3600 fps on a 55 gr. Sierra bullet.
Impossible to double load these cartridges but 2-3 grains more than max is too hot, certainly.
All in all, I changed 5 things in my reloading, as I was taught poorly by another reloader and a lot of bad advice online from other articles, forums....not this forum!
I never go over book max now as I just look for another primer or powder. Call me "chicken.."
I might be leaving an accuracy node on the table, but it's not worth the risk to me. Breeching two primers on a 7 mag taught me a valuable lesson, even though I didn't have heavy bolt lifts at .5 gr over, it eventually got me. Was on the ragged edge and never, ever knew it until that one crappy day. Never again.

On the Hodgdon website for the 6.5-06 with 129 grain bullet they list a charge of 42.0 grains of IMR 4831 as giving 51,000 psi and 47.0 grains as giving 62,700 psi. I'm using 54.0 grains with no sign of excess pressure. Something is wrong with their data. I contacted them and they assured me that the pressures were correct altho they did not verify that the charge weights were correct. Frankly these data are not consistent with either .270 Win or .25-06 loads using similar weight bullets. I'm at 54.0 grains of IMR 4831 with a 117 grain bullet in a .25-06.

Just goes to show that you should take all of that data with a grain of salt.

 

[emp1953]

I would say barrel obstruction. Unless you loaded 35g of pistol powder, I can't think of anything that would cause a pressure spike like that.

You didn't just pierce a primer or lock the bolt shut. It needed to vent pressure and it wasn't coming out of the front so it banana peeled the barrel. Any chance you put a round that was not 22-250 in the chamber?

I agree on the pistol powder. 35g of red dot would blow anything up. Take a couple rounds apart and check them out carefully. It does sound like barrel obstruction.

 

[Bob Wright]

On the Hodgdon website for the 6.5-06 with 129 grain bullet they list a charge of 42.0 grains of IMR 4831 as giving 51,000 psi and 47.0 grains as giving 62,700 psi. I'm using 54.0 grains with no sign of excess pressure. Something is wrong with their data. I contacted them and they assured me that the pressures were correct altho they did not verify that the charge weights were correct. Frankly these data are not consistent with either .270 Win or .25-06 loads using similar weight bullets. I'm at 54.0 grains of IMR 4831 with a 117 grain bullet in a .25-06.

Just goes to show that you should take all of that data with a grain of salt.

I go to:
-The bullet mfr data on powder reccomendations
-I cross check the powder mfr data
-I take a look at burn rates as they rank.
Then I stay low and work up, but not exceed the max charge of the higher pressure of that data set.
You bet there is loading book errors, and I rely more on powder mfr data.
It's the trust factor and I don't trust one data set....
Powders I didn't ever try, suddenly became go to powders once I found them to be true to the data provided.

 

[1953greg]

Ok here's what i found out this afternoon, I'm an idiot but a live one

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.

4.5g is a lot too much but i doubt that alone would cause that failure
dont kno and dont intend to find out
but back n the day jus for chit n giggles i hav loaded 220 swift w/ 3031 case full to bottom of neck bout 42g jus to see how much it could handle. crep up 1 grain at a time. all i got were sticky bolts, blown primers, and ruptured cases.
and thats prolly 5 grains too much.
and 3031 is a tick hotter than varget
obtw.....it was a stevens...aka savage...and still shoot it today

 

[emp1953]

On the Hodgdon website for the 6.5-06 with 129 grain bullet they list a charge of 42.0 grains of IMR 4831 as giving 51,000 psi and 47.0 grains as giving 62,700 psi. I'm using 54.0 grains with no sign of excess pressure. Something is wrong with their data. I contacted them and they assured me that the pressures were correct altho they did not verify that the charge weights were correct. Frankly these data are not consistent with either .270 Win or .25-06 loads using similar weight bullets. I'm at 54.0 grains of IMR 4831 with a 117 grain bullet in a .25-06.

Just goes to show that you should take all of that data with a grain of salt.

I always get my data from as many sources as I possibly can and see what looks reasonable and what does not. I find a chronograph an invaluable tool to tell you a whole lot about your reloads. If there was a squib load or a primer only load, after firing it, when you looked at the chrony and saw a big fat zero. it should prompt you to look for a bullet that didn't come out of the barrel.

 

[couesaddict]

One thing that makes me seriously nervous is using a single scale, I still use a digital but I throw it on my beam scale as a sanity check before dropping it in a case. Once you see just how bad it can go it's sobering in a big way!

Had a heck of a time about a month or two in with my digital scale with the same issue. Called them and they said to clean it with windex to kill the static that had built from powder flowing down the tube. Made a huge difference. Did that and went to double checking everything with the beam. Even clean and free of static the two scales don't agree too well. I trust the beam the most.

 

[DSheetz]

I am glad you found a problem so that you can fix it . I am very cautious when I reload . I check my powder thrower before I put any powder in to make sure there isn't any already in it . I weigh every charge and put it in a case then put a bullet in point down in the case and check that case before I seat the bullet . I had an incident with a 17 hmr when I went to chamber a round the tip of the bullet caught and the bullet was pushed back into the case dumping powder in the action and chamber . I caught it when it happened and didn't try firing it . I'm glad I was paying attention as it really didn't feel like any thing wasn't the same and have been told that is why not many 17 hmr's are semi auto .

 

[simo hayha]

Ok here's what i found out this afternoon, I'm an idiot but a live one

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.

I knew you were on the hot side before this info.

Now put bullet weld on top of a hot load and boom.

Bullet weld is a chemical reaction type situation. Google it good thread on accurateshooter

Benchrest guys will load long. Then bump the bullet back the day before a match. Thus avoiding bullet weld

 

[simo hayha]

If your brass was long and pinching the bullet. The bolt would have been hard to close.

 

[antelopedundee]

Had a heck of a time about a month or two in with my digital scale with the same issue. Called them and they said to clean it with windex to kill the static that had built from powder flowing down the tube. Made a huge difference. Did that and went to double checking everything with the beam. Even clean and free of static the two scales don't agree too well. I trust the beam the most.

Which scale comes the closest to accurately weighing a bullet? A 140 grain match bullet for instance.

 

[couesaddict]

Which scale comes the closest to accurately weighing a bullet? A 140 grain match bullet for instance.

Beam is the most consistent. It doesn't seem to vary much at all with barometric pressure like the digital does either. With all this being said though, I find it hard to believe the overcharge based on the pulled bullets could blow a rifle apart like the op's. I've never done it, thank god, so I don't have any insight on the root cause. Spooky to say the least!

 

[MNbogboy]

Beam is the most consistent. It doesn't seem to vary much at all with barometric pressure like the digital does either. With all this being said though, I find it hard to believe the overcharge based on the pulled bullets could blow a rifle apart like the op's. I've never done it, thank god, so I don't have any insight on the root cause. Spooky to say the least!

The pressure exceeded what the brass case head was capable of holding. Once the case head let go it was like a grenade going off between the bolt (which held) and the barrel. Most actions can't relieve that much gas & shrapnel at the same time. When a primer blows there is also high pressure gas but not in that volume.
Pressures are dictated by the brass case, in the case of a savage there is "unsupported" brass. If you look at the bolt head you can see how the brass "took out" the weakest parts of the bolt head. As the gasses "rushed" by the bolt lugs the also wiped the rear baffle off the bolt head. The rifles are really strong for holding the forces they were intended with a lot of safety factor. Brass too is designed to hold so much but safety factors are not as high.
If you get a sticky bolt lift or ejector mark you are stressing your brass way beyond what it was designed for. If you ever blow a primer you are now playing with fire (excuse the pun). It is a totally scary experience. At that point you are right next door to what happened to normyt our OP.
A consensus among several reloading manuals & data is where you want to be unless you have pressure measuring capability.
All it takes is one defective piece of brass and it may injure or kill you or an innocent bystander.

 

[crkckr]

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

 

[duke75]

Went shooting yesterday, shot about 5 shots and on 6th shot this happened.
Reloads from a couple years ago , store in ammo box in a shooting bag.
Rifle is a 22-250 Savage Model 10
Bullets are 55Gn Hornady V-Max
35GN of Varget Powder
Been doing this recipe for approx. 4 years, have never had problem.
No signs of over pressure until this incident, happily no injuries/casualties (except gun,LOL)
Any Ideas out there

View attachment 148591 View attachment 148592

Are these reloads loaded by you, or were they purchased? It appears that you encountered an overloaded cartridge more so than a under load, the photos show tremendous pressure build up that is indicative of an overcharge. The Savage Model 10 is not as robust, as say a Win. Mod. 70, which probably not have failed. Personally I wouldn't own a Savage, and do check your loads more carefully if you were responsible. This incident could have resulted in your death and those standing nearby. You were very lucky. Thank God I would and do.