This could have ended a LOT worse

J-B Welder, I can explain the failure rather easily. this was a failure of your brass. it was brittle and/or fatigued. this failure is called a "dog bone split". it is tell-tail of brittle brass or over worked brass. this happens to brass once the back half of it has been sized too many time and it just will not be elastic enough to take the pressure. do not believe this is your gun's chamber. I have seen this a great many times even before I was a gunsmith and saw this professionally. I have this happen to me a lot on used brass I get in and sell out of my shop. someone brings in their husband's/dad's old brass and there is a few pieces that have more than 7 reloadings on them and they just do not survive much longer. I have had it frequently happen on my test fire factory loads over 30 years old.
 
J-B Welder, I can explain the failure rather easily. this was a failure of your brass. it was brittle and/or fatigued. this failure is called a "dog bone split". it is tell-tail of brittle brass or over worked brass. this happens to brass once the back half of it has been sized too many time and it just will not be elastic enough to take the pressure. do not believe this is your gun's chamber. I have seen this a great many times even before I was a gunsmith and saw this professionally. I have this happen to me a lot on used brass I get in and sell out of my shop. someone brings in their husband's/dad's old brass and there is a few pieces that have more than 7 reloadings on them and they just do not survive much longer. I have had it frequently happen on my test fire factory loads over 30 years old.
Thank you to all those providing reassurance that this was not due to excessive pressure. I still consider it to be due to multiple errors on my part, most notably not sufficently educating myself about brass and not inspecting these cases thoroughly enough.

I'm curious about these dog bone splits. If they happen to full-charge cartridges are they more dangerous than what this turned out to be? Can they damage the bolt or chamber?
 

Almost 28.5 (link) vs. 25.0 (OP) according to above link with .243 & 80 Hornady SSP. More citations needed.

Or .6 of max 38gr. for .243W with 80 cup & core bullet for 22.8. (Hodgdon data). 22.8 at .6 of max (Hodgdon data) vs. 25 OP.

OP's charge weight well within limits.

Defective brass (1), soft annealed head/web (2, range brass?), wrong powder (3), deteriorating powder (4, corrosive nitrous oxides) or erratic detonation effect (5, doesn't happen every time).

Brass is hardened by working to reduce crystal size then annealed to soften at neck/shoulder to enlarge crystal size making the brass more ductile for holding bullets. Excessively soft brass at head is possible. Increased work hardening via normal firing/use would enlarge primer pockets by exceeding brass elastic limits causing primers to fall out. The OP did not indicate loose primer pockets.

The acceptable SAAMI pressure limits for the .243 Win are less than 60,000 psi. I fail to see how normal firing would make the brass "fatigued" without enlarging primer pockets.

Smokeless powder undergoes continual decomposition and corrosive components result. Possibly those "test fire factory loads over 30 years old" had that happen.

If that range brass is not clean & shiny , I'm not picking it up - recycle only.
 
Last edited:
Could something similar to what the OP posted cause a rifle to explode?

I have picked up brass on a M249 range before that had damage similar to what the OP posted.
No, it is practically impossible for a low pressure round to blow up a rifle unless there are other issues like a bore obstruction.
All the talk of S.E.E. (Secondary Explosion Effect) has NEVER been produced in a lab.
I have used many reduced loads with H4895 at 60% of a max load without issue.
Tried a reduced load with H4350 in a 300WM and had hangfires, no S. E. E. or other nasty stuff, just click….boom.
On my pressure trace, I have witnessed secondary peak pressure that is above 80,000psi just as the bullet leaves the muzzle, nothing happens to the brass. Unsure what causes it, but it has been suggested that it is the plasma igniting on bullet exit. The graph it produces is rather strange looking.

Cheers.
 
So would this be happening to older loaded cartridges also? How long would you consider it still safe? I have some older ammo and wonder if I should just pitch it or not? Also, what about ammo hoarders? The guys that brag about having 10's of thousands stored for the big one. Are they at risk of this happening during a heated fire fight?
 
Secondary Explosion Effect

Says in this article that at least one ballistic lab has reproduced it at will. It's a known, and now proven, phenomenon.

OP, in my opinion you did three things wrong:
1 and 2- What you sent that girl out with was unproven and unknown. "New" used brass and an experimental load.
3- You sent her out with a rifle that was specifically dangerous to her. Even if her dad wants to ignore the risks, he wouldn't be doing it with my rifle.
 

Says in this article that at least one ballistic lab has reproduced it at will. It's a known, and now proven, phenomenon.

OP, in my opinion you did three things wrong:
1 and 2- What you sent that girl out with was unproven and unknown. "New" used brass and an experimental load.
3- You sent her out with a rifle that was specifically dangerous to her. Even if her dad wants to ignore the risks, he wouldn't be doing it with my rifle.
I can almost agree with you completely. I don't feel the load was entirely experimental. As I stated, I followed the powder manufacturer's instructions closely, and have fired at least 30 rounds of this load in this gun without incident. That's in addition to the rounds fired during load work up. I don't know how many rounds you think it takes to "prove" a load, but in my mind it was no longer experimental.
 
Last edited:

Says in this article that at least one ballistic lab has reproduced it at will. It's a known, and now proven, phenomenon.

OP, in my opinion you did three things wrong:
1 and 2- What you sent that girl out with was unproven and unknown. "New" used brass and an experimental load.
3- You sent her out with a rifle that was specifically dangerous to her. Even if her dad wants to ignore the risks, he wouldn't be doing it with my rifle.
I know of that article and also the S.E.E in question.
It has NEVER been proven using canister grade powder.
I have seen 3 such rifles that were an unknown pressure event that burst the firearm…after extensive analysis, all 3 had either a partial bore obstruction or the WRONG powder was used.
The S.E.E. in question was with military 50BMG and 20mm cannon powder in quantities of half or less than half case fill.
It is very difficult in normal circumstances to get a powder to FLASH IGNITE, also Nick Harvey is known to bend the truth somewhat to answer reader questions.

Cheers.
 
As I mentioned in the Free Components for Kids thread, I let my friend borrow my .243 for his daughter to try out, and gave them some reduced load rounds as well as some full-strength (not max) loads. Well, Monday morning I got a text from Stewart with the words "We had a little problem" and this picture.

View attachment 287736
I called him right away and was relieved to learn that nobody was hurt. In fact, he said nobody noticed anything until his daughter opened the bolt and the spent case did not come out. Wisely, they put the gun aside and moved on to shooting his wife's .308. Later in the day, a cleaning rod easily did the trick and they were able to get the case out of the chamber with just a couple of taps.

When I met Stewart to get my gun back, we took a look at the bolt face. Here are a few pics from different angles, before and after cleaning it with some Hoppe's No. 9 solvent.
View attachment 287746 View attachment 287747View attachment 287750View attachment 287751

I did not see anything that stood out to me, but those with more expertise and experience might notice something important that I missed. I don't have a bore scope and therefore can't really get a good look at the chamber. I think it might be a good idea not to shoot the gun again until I have a gunsmith take a peek in there and tell me if there was any damage.

Stewart's wife happened to be videoing her daughter shooting, and she sent me a slo-mo of the shot. In it, you can see a puff of smoke come out near the bolt. Nobody, not even the shooter, noticed the puff of smoke as it happened; they only saw it when they looked at the video later. Unfortunately, I can't figure out how to attach the video, but if I did you'd see she's a lefty shooting my right-handed gun, without safety glasses, so the fact that smoke was the only thing expelled around the bolt is doubly lucky.

So after profusely apologizing to my friend repeatedly, and thanking whatever supreme power in the universe it was that saved me from a lifetime of remorse for maiming a child, I naturally started to think about what caused the incident. The two most likely things would seem to be too much powder or faulty brass. Here are the particulars of the load:

Bullet: Hornady #2430 80 grain FMJ
Seating depth: 0.035" off lands
Powder: 25.0 grains of H4895
Primer: WLR
Case: Winchester Super-X

The powder charge was based on load data from the Hodgdon and Sierra websites, since my Lyman 50th edition didn't list H4895 for 80 grain jacketed bullets. Hodgdon showed starting and max loads as 35.0 and 38.0 grains respectively, and Sierra indicated 32.8 and 35.4. As many of you know, H4895 is a powder specifically noted by Hodgdon as being suitable for reduced loads. Using the instructions from their website, I multiplied the maximum load (38.0 grains) by 60% to get 22.8 grains as a starting load. I actually started my load work up at 23.5 and eventually found that I got good results between 25.0 and 25.3 grains.

The brass was purchased online from an individual, not a retailer. The seller indicated they were new primed brass, but they varied quite a bit in their condition. Some were shiny bright like new, and some were corroded inside. In fact, during load development about a quarter of them failed to fire, which I attributed to primer corrosion. Of the remaining brass after that, I set aside the worst of them, and the ones that had what I judged to be mild corrosion I decapped, wet tumbled in Lemi-Shine and Dawn (no media) and put fresh primers in them. Since then I have fired 30 rounds of this load in this gun without incident.

I use a single stage press to reload and weigh each charge with a Lyman Micro-Touch 1500 digital scale. When loading fired brass, I inspect each case before sizing/decapping, after tumbling, and after bullet seating with a small hand lens, rotating the case a full turn each direction while checking the neck/shoulder area and again looking at the base. Because these were supposedly new cases, it's quite likely that I did not give them the thorough inspection I normally give to fired brass. I honestly don't recall. As I noted above, the corrosion was on the inside of the cases, not on the outside. Would an inspection of the outside of the cases have made me reject any of them? Can't say for sure, but I still should have given them a thorough look. Maybe I should have discarded them immediately, as I couldn't really get a good look inside. Several people told me they should be good to shoot, but they were going on my description of the corrosion, not first-hand observation. It may be unlikely that the corrosion created a weak spot in the case, but it's not impossible. If it was enough corrosion to make the primer go bad, who knows what it did to the case?

After weighing a powder charge and pouring it into a case, I immediately seat the bullet, as recommended in the Lyman reloading manual. Some people like to charge all their cases at once and then seat their bullets, but I feel the Lyman procedure makes it less likely to double charge a cartridge. Does that mean I couldn't have put a double charge in one or more of them? Absolutely not. In this instance, a double charge would have been 50 grains, 12 grains (32%) over book max. Not as bad as doubling a max load, but still a significant overload.

Typing all that out, checking my reloading notes, etc. helps me to go over things in my head and get them all straight. Having done that, here are the decisions made and lessons learned:
  1. Always inspect every case, regardless of it's initial apparent condition. Even new cases can have flaws that made it past the Quality Control department of the manufacturer.
  2. I can no longer trust this particular bunch of brass, because I can't definitively determine the cause of the case rupture. Accordingly, I'm going to put my new-to-me collet-type bullet puller to use and disassemble all these rounds, re-use the powder, bullets and primers, and chuck the brass. It's just not worth the risk. If after pulling the bullets it's obvious which cases are virgin brass I might save those, but any that don't look brand new are out.
  3. Re-double my efforts to make sure I am not interrupted or distracted during loading, especially during the charging/seating process. I don't recall any interruptions that may have caused me to double charge a cartridge, but my memory sucks these days so it's a very real possibility.
  4. I'm having serious second thoughts about letting other people shoot ammunition I reload, at least until I'm more experienced. It felt awesome to think I was helping a youngster choose their first gun and shoot their first deer; I don't even want to imagine how I would have felt if Caleigh had been disfigured, blinded or worse.
I would be interested to hear what other things jumped out to people that they think I should be considering or changing in my reloading habits. Any thoughts are welcome.

Thanks for reading. Hopefully others pick up something useful from my experience.
Reduced powder loads can be dangerous because more horizontal powder surface is exposed to the primer flash causing detonation and pressure spikes. In my experience, achieving less recoil for new shooters, loading Trailboss Powder is a safer method because it fills the cartridge and creates deflagration (controlled burn and gas that pushes the bullet out of the barrel). Hope this helps.
 
Reduced powder loads can be dangerous because more horizontal powder surface is exposed to the primer flash causing detonation and pressure spikes. In my experience, achieving less recoil for new shooters, loading Trailboss Powder is a safer method because it fills the cartridge and creates deflagration (controlled burn and gas that pushes the bullet out of the barrel). Hope this helps.
Not when using H4895, it is a powder that can be reduced safely. I did it myself after working at the ADI plant here in Australia where it is made. It goes by AR 2206H here.
It is the only rifle powder I know of that can be reduced 40% safely and performs perfectly fine without the need for fillers and other such nonsense.

Cheers.
 
Hello good people, young man I don't think I would worry about your reloading you appear to be doing things well, as I read more like some of you good people I have had the same thing happen and it was from old brass also had some old loaded ammo and it blew smoke out of the bolt, when I ejected the round it threw out the bottom piece and I was amazed the base up about a half inch was separated perfect as one would have cut it. Keep doing what your doing just be careful on buying the older brass if possible..
 

Says in this article that at least one ballistic lab has reproduced it at will. It's a known, and now proven, phenomenon.

OP, in my opinion you did three things wrong:
1 and 2- What you sent that girl out with was unproven and unknown. "New" used brass and an experimental load.
3- You sent her out with a rifle that was specifically dangerous to her. Even if her dad wants to ignore the risks, he wouldn't be doing it with my rifle.
I don't know enough to have an opinion on S.E.E., however the article reads like a FOF story (Friend of a friend). "However, in more recent times S.E.E has been reproduced at will in at least one ballistic laboratory. " which lab?
 
Not when using H4895, it is a powder that can be reduced safely. I did it myself after working at the ADI plant here in Australia where it is made. It goes by AR 2206H here.
It is the only rifle powder I know of that can be reduced 40% safely and performs perfectly fine without the need for fillers and other such nonsense.

Cheers.
Interesting tidbit. Thank you for sharing
 
I don't know enough to have an opinion on S.E.E., however the article reads like a FOF story (Friend of a friend). "However, in more recent times S.E.E has been reproduced at will in at least one ballistic laboratory. " which lab?
It was the Norma lab. Testing 50BMG and 20mm cannon powder, which are a powder similar to US869, US970 etc, which are a canister powder but swing in burn rate too much to be sold to the general public.
Contrary to people's observations and assumptions, to be sold as a canister grade powder, it MUST stay within +/- 3% of the ORIGINAL powders burn rate as shown in a calorimeter bomb, if it falls outside of these parameters it can ONLY be sold as BULK.
People bandy about that powder in canisters are blended…no they are not.
Worked where it's made, if it doesn't come up to snuff, it never sees the shelves. Believe me, when we're talking a train load of powder, they're striving to get that powder the same every batch, because bulk powder gets bid on, not just sold at a particular price point.
Anywoo, there you have it.

Cheers.
 
Top