S.e.e. ??

[racepres]

Was gonna put this under case forming...But... Not Funny
documented to my satisfaction. I inadvertently put 26 grains of W748 instead of 36gr. into the 8X57 with 170gr Boolit
Double checked the charge in fact... physically, Not the Book ... Obviously
If yer gonna be Dumb...ya better be Tough...Or, Use a 98 Mauser.. Only My Pride, and Confidence in my Old Feeble Mind, were Shaken....Oh...And Nerves!!!!
Only thing I can come up with is S.E.E. Powder was definitely W748...charge was double Checked (even if Wrong).. old Mauser is Not any Worse for Wear!!!!
I never had anything like that, and been reloading since 1979 or so...
Be Careful You Old Farts!!!!... (maybe younger guys too)
Almost too embarrassing to Share... But... gettin old is about Sharing...
311302

[BLAHUT]

?????????

[racepres]

?????????

Ok...Maybe Not SEE... What do You think Happened???

[Hannibal]

Can you post a few more pictures from other angles? Is the case exactly as it was when removed or have you done some cleaning/wiping on it?

Never saw a case head do something like that while in battery. Were you opening the bolt when this occurred? Something seem very odd.

[turtlezx]

i would think so how else would 10 grs under blow

[BLAHUT]

You state : I inadvertently put 26 grains of W748 instead of 36gr. : Lite load, blowing case ? Wrong powder ? Old and weak brass ? Head space ?
Was bullet stuck in barrel ? Plugged barrel ? Fired out of battery ? What little can be seen brass looks old and brittle ? ?????????

[Hannibal]

The thing is, if the rifle and barrel are undamaged yet the case head looks like that it couldn't have been in battery/bolt closed.

So either you had a hang fire and opened the bolt, the bolt wasn't in position/closed when fired or maybe ...... and this is a stretch but did the firing pin hang up and move forward when you started opening the bolt?

The last 2 situations would mean you definitely do have something wrong with your rifle.

[racepres]

Can you post a few more pictures from other angles? Is the case exactly as it was when removed or have you done some cleaning/wiping on it?

Never saw a case head do something like that while in battery. Were you opening the bolt when this occurred? Something seem very odd.
I can get more pics...tomorrow, or so.. case is at shop.
I believe the tearing etc you see happened when I forced (literally beat) the bolt open.. driving the case out after that was Not that big of a deal.. but, not for cleaning rod.. Dowel, and Hammer


You state : I inadvertently put 26 grains of W748 instead of 36gr. : Lite load, blowing case ? Wrong powder ? Old and weak brass ? Head space ?
Was bullet stuck in barrel ? Plugged barrel ? Fired out of battery ? What little can be seen brass looks old and brittle ? ?????????
Exactly as I stated... boolit exited.... Load Too Lite with Ball Powder!!! Nothing in barrel...I check religiously as we have Mud Daubers.
None of my Mausers can/will fire out of battery.. by now I believe I know enough to Close the Bolt!!!
Old brass...Yup... discolored but... the rest of that lot is still working Fine with 36.0 grains vs 26!!!
Headspace???? As Many cartridges as I have Fireformed... I sincerely Doubt headspace can/will/could do anything remotely resembling that!!

Nope... I'm sticking to SEE, caused by too light a Charge, until ??? a plausible answer surfaces...
Again nothing wrong with that Old VZ24!!! Still functions very well indeed...
And... the case got mis-shapen and torn opening bolt (Mausers extractors Are Tough as Chicken Lips)
this aint no Remchester.

[country gent]

Looks like the case gave out into the extractor cut in the bolt.

How was the bolt lidt. I would consider detonation. They didnt recommend light loads for a lot of the Winchester ball powders.

[racepres]

Looks like the case gave out into the extractor cut in the bolt.

How was the bolt lidt. I would consider detonation. They didnt recommend light loads for a lot of the Winchester ball powders.
Probably exactly what happend when the Case head let go.. Bolt discolored terribly (black, Not white like I expected), wiped off..
Edit; L>ooking again at rifle...silly me... no Extractor "slot" on a Mauser... but, thinking brass "flowed" out the unsupported face where the Ctg would come up from magazine..
I double checked just now, and that brass, does appear discolored rather badly...and though 36.0 gr should be a light load, the primer pockets seem loose... prolly retire that brass...as This was an unpleasant experience...and a reminder...My Mind Aint what it used to be!!! Gotta slow down.... smell the coffee...
I am currently wondering if I could reproduce such an event with lighter than recommended Charge... From a Distance If I tried it...

[LAGS]

I have seen several firearms that were damaged by Too Light of a reload.
It seems with some powders.
If the case is not up to the Minimum Charge for that powder.
The powder Flashes Over and creates excessive pressure.
A friend had that happen with a 22-250.
It blew the bolt apart and cracked the receiver.
To avoid that with intentional light loads , you have to put a filler in the case to take up the extra air space and keep the powder back against the primer.
Usually minimum loads are like 60% of the case capacity.

[murf205]

I had a 22-250 pull that stunt with 4320 and a 70 gr Speer semi spitzer. Smoke from the action and primer fell out with a middle of the road charge. After a long bit of searching, it turns out that the very long bearing surface of that bullet raises pressures very quickly. I still use that bullet in my 223 but I sneaked up on the load from WAY behind and I use BL-c2 now. I'm not sure what caused your event but those thrills, we can do without. WEAR THOSE GLASSES.

[racepres]

I have seen several firearms that were damaged by Too Light of a reload.
It seems with some powders.
If the case is not up to the Minimum Charge for that powder.
The powder Flashes Over and creates excessive pressure.
A friend had that happen with a 22-250.
It blew the bolt apart and cracked the receiver.
To avoid that with intentional light loads , you have to put a filler in the case to take up the extra air space and keep the powder back against the primer.
Usually minimum loads are like 60% of the case capacity.

No Fillers for me...Ever...and I would Not claim that (X) percent full was somehow magic...as 12gr of Red Dot with a Non gas check 170 boolit works very well indeed in that 8X57, again... no Filler.. Tho 26 gr of 748 is prolly around 50% of available space in that loading..
I try to treat Ball Powders with more respect...generally about 75 - 80% of available space..I just blew this one Ctg...actually more than one, but I pulled the remainder and re-charged appropriately!!!



I had a 22-250 pull that stunt with 4320 and a 70 gr Speer semi spitzer. Smoke from the action and primer fell out with a middle of the road charge. After a long bit of searching, it turns out that the very long bearing surface of that bullet raises pressures very quickly. I still use that bullet in my 223 but I sneaked up on the load from WAY behind and I use BL-c2 now. I'm not sure what caused your event but those thrills, we can do without. WEAR THOSE GLASSES.
Been wearing glasses since I arrived "Over the Hill", courtesy VA Thank You...

[405grain]

Just an FYI for those who suggest that this was caused by the rifle discharging while the bolt was partially open: 98 Mauser's are designed so this won't happen. There is a slot forged inside the bolt body that mates with a spade shaped extension on the face of the flange on the firing pin which retains the firing pin spring. Unless the bolt is fully closed the firing pin cannot move all the way forward, and the firing pin tip cannot extend beyond the bolt face.

An under charge of a slow burning ball powder can result in a pressure spike. This is less likely with fast or medium burning rate powders, but can occur with with small charges of slower powders. Under these circumstances the powder charge does not ignite uniformly. The abnormal ignition causes the pressure to build too slowly for proper burning. As the pressure finally builds up to the point that the powder charge finally fully ignites, this can cause supersonic shock waves to develop inside the case. It is these shock waves which can cause a rapid compression of the burning powder charge (which can cause an exponential increase in burning rate), and create a feedback loop which generates significant over pressure inside the cartridge.

The failure mode of the OP's cartridge is exactly what would be expected in a 98 Mauser. Unlike, say, a Remington model 700, the case head in a Mauser is not fully supported. With pressures that cause brass to flow, the case head can separate just in front of the extraction groove. The gas from this rupture would flow both down into the magazine well (where if it had swollen the magazine it would have probably cracked the stock), and also back the feed rails towards the shooters face. The flange on the front of the bolt shroud would have diverted the bulk of this gas, and a large portion of it would have passed out through the thumb cut for the stripper clips. This incident is a fine example of the excellent gas handling characteristics of the 98 Mauser, and also a reminder to remain diligent when reloading.

[Hannibal]

Just an FYI for those who suggest that this was caused by the rifle discharging while the bolt was partially open: 98 Mauser's are designed so this won't happen. There is a slot forged inside the bolt body that mates with a spade shaped extension on the face of the flange on the firing pin which retains the firing pin spring. Unless the bolt is fully closed the firing pin cannot move all the way forward, and the firing pin tip cannot extend beyond the bolt face.

An under charge of a slow burning ball powder can result in a pressure spike. This is less likely with fast or medium burning rate powders, but can occur with with small charges of slower powders. Under these circumstances the powder charge does not ignite uniformly. The abnormal ignition causes the pressure to build too slowly for proper burning. As the pressure finally builds up to the point that the powder charge finally fully ignites, this can cause supersonic shock waves to develop inside the case. It is these shock waves which can cause a rapid compression of the burning powder charge (which can cause an exponential increase in burning rate), and create a feedback loop which generates significant over pressure inside the cartridge.

The failure mode of the OP's cartridge is exactly what would be expected in a 98 Mauser. Unlike, say, a Remington model 700, the case head in a Mauser is not fully supported. With pressures that cause brass to flow, the case head can separate just in front of the extraction groove. The gas from this rupture would flow both down into the magazine well (where if it had swollen the magazine it would have probably cracked the stock), and also back the feed rails towards the shooters face. The flange on the front of the bolt shroud would have diverted the bulk of this gas, and a large portion of it would have passed out through the thumb cut for the stripper clips. This incident is a fine example of the excellent gas handling characteristics of the 98 Mauser, and also a reminder to remain diligent when reloading.

Could someone direct me to or post an image of such a chamber? This is something new to me so I stand corrected. Pardon my mistake and any confusion I caused.

Learn something new every day. And sometimes something old is new.

[Hannibal]

I can get more pics...tomorrow, or so.. case is at shop.
I believe the tearing etc you see happened when I forced (literally beat) the bolt open.. driving the case out after that was Not that big of a deal.. but, not for cleaning rod.. Dowel, and Hammer


Exactly as I stated... boolit exited.... Load Too Lite with Ball Powder!!! Nothing in barrel...I check religiously as we have Mud Daubers.
None of my Mausers can/will fire out of battery.. by now I believe I know enough to Close the Bolt!!!
Old brass...Yup... discolored but... the rest of that lot is still working Fine with 36.0 grains vs 26!!!
Headspace???? As Many cartridges as I have Fireformed... I sincerely Doubt headspace can/will/could do anything remotely resembling that!!

Nope... I'm sticking to SEE, caused by too light a Charge, until ??? a plausible answer surfaces...
Again nothing wrong with that Old VZ24!!! Still functions very well indeed...
And... the case got mis-shapen and torn opening bolt (Mausers extractors Are Tough as Chicken Lips)
this aint no Remchester.


Sorry for my mistake. As I said above I learn something new every day. Glad you are ok.

[rockrat]

Had that happen with a S&W 29, using AA#9 and too light a charge. Just a "pop" and a pinkish flash as the top of cylinder departed the gun.

[405grain]

The bottom of the bolt face on a Mauser is open so that it can strip cartridges from the magazine. There has to be a small open gap between the breech face and the bolt face for the claw on the extractor to reside. Because of these properties, the cartridge base is supported pretty well, but is not fully supported. For the best explanation on how the safety feature on the firing pin works, check out this video:
https://www.youtube.com/watch?v=XnHMBrtQNtE

Editing this post because I just had an afterthought. When I load cast rifle cartridges wild ball powders (like BLC-2) I use magnum primers. I think that this produces better ignition with ball powders. Generally, the fuller the case is the better.

[racepres]

405 has done a much better job of Explanation than I could have.. The brass certainly "flowed" such that it took a "club" to open the bolt!!! Making case Forensics difficult. Unlike rockrats experience... this was quite loud, and again like 405 says.. gasses went out the side (probably deflected by the bolt shroud, but I cannot "replay" it) and certainly down into the mag well...as black soot was evident there too.
Unnerving as all get out.. Again... Love My Mausers... Tho I may should treat them Better!!!!

[Hannibal]

The bottom of the bolt face on a Mauser is open so that it can strip cartridges from the magazine. There has to be a small open gap between the breech face and the bolt face for the claw on the extractor to reside. Because of these properties, the cartridge base is supported pretty well, but is not fully supported. For the best explanation on how the safety feature on the firing pin works, check out this video:
https://www.youtube.com/watch?v=XnHMBrtQNtE

Editing this post because I just had an afterthought. When I load cast rifle cartridges wild ball powders (like BLC-2) I use magnum primers. I think that this produces better ignition with ball powders. Generally, the fuller the case is the better.

OK. I understand all that and how it's supposed to function. I was hoping someone has a barrel outside the action or a cut-away view so I can see the unsupported area that's being discussed.

I appreciate your help guys. I'm always happy when I can increase my knowledge and understanding.

[racepres]

OK. I understand all that and how it's supposed to function. I was hoping someone has a barrel outside the action or a cut-away view so I can see the unsupported area that's being discussed.

I appreciate your help guys. I'm always happy when I can increase my knowledge and understanding.
I have more than one barrel laying around here..The entire web/head are unsupported by the Barrel..I would guess just here, that almost an eighth of an inch hangs out of the barrel.. I will measure tomorrow.. the Intermediate Mauser has a Cut out of a Safety Breach type extension, like a Remington...but Larger.. the good ole 98..Nope.. the bolt kinda surrounds the head.. but Not completely.. the Strongest part of the Cartridge is just kinda hung out in space,so to speak.. Never had that part fail, Until Now!!!
Maybe tomorrow I take pics of an Action, Bolt, Barrel... all layed out...I gots 'em around here...

[Hannibal]

I have more than one barrel laying around here..The entire web/head are unsupported by the Barrel..I would guess just here, that almost an eighth of an inch hangs out of the barrel.. I will measure tomorrow.. the Intermediate Mauser has a Cut out of a Safety Breach type extension, like a Remington...but Larger.. the good ole 98..Nope.. the bolt kinda surrounds the head.. but Not completely.. the Strongest part of the Cartridge is just kinda hung out in space,so to speak.. Never had that part fail, Until Now!!!
Maybe tomorrow I take pics of an Action, Bolt, Barrel... all layed out...I gots 'em around here...

That would be fantastic. Thank you for sharing your knowledge and experience.

I apologize if this is detracting from your message, I never intended to do so.

Be careful in the reloading room folks! Mistakes have consequences.

[Hick]

26 grains is down around 70% fill or even lower. IF you have below 70% in that case, and you are unlucky, you can get the powder lying sort of lengthwise in the case with the flash hole not covered in powder. When you do that you expose a whole lot more surface area of the powder to the flash of the primer. This can burn the powder faster and raise the pressures faster than normal. I haven't done the math for 8 x 57, but in a 30-06 case you can actually speed up the burning by a factor of 6 (yes-- six times faster). That will raise the pressure quite a bit.

[megasupermagnum]

How can you be so certain this was a high pressure event? Why is SEE always the go-to for anything that can't be explained with an overload?

It sure looks to me that you loaded a case 1 too many times, and got a case head separation. At least that should be at the top of your suspect list, and SEE should be way down the list after wrong powder, or headspace problem.

[racepres]

How can you be so certain this was a high pressure event? Why is SEE always the go-to for anything that can't be explained with an overload?

It sure looks to me that you loaded a case 1 too many times, and got a case head separation. At least that should be at the top of your suspect list, and SEE should be way down the list after wrong powder, or headspace problem.
Welp... I know surely that it was Not an overload...as I said...I pulled the rest...all the same 26 Gr...I am at least that careful.
Having had head separations from just plain too many full length sizings...I am confident...nope...Not that...especially since the remainder of that batch is not showing any ...zero, signs of case head separation..
All the headspace problems in the world do Not have such a result.. it does end up with head separation..Only if full length resized ...this has Never Been Full Length Resized.!!! Having as many Wildcats as I do "normal" ctgs...I do know some small bit about headspace.. Headspace problems...always result in Less Pressure... I do Not think Brass flows under Lower Pressure.
If SEE was my go to....I should think I would have had this experience 40 years ago
But... IDK ... Maybe Im a *******!!!!

For those casting doubt...Carry on Blissfully...for Careful people heed..Reduced (excessively) loads, really can be a problem...

[405grain]

A head separation is caused by improper head space. A case head failure with plastic deformation is caused by too much pressure. In this specific instance, what is being shown is what a secondary explosive event would look like. The OP said that he used a powder charge that was much lower than normal, so this is not an over charge event. Also, when a case is loaded too many times, the failure mode is usually case mouth splitting, not a case head failure.

[racepres]

A head separation is caused by improper head space. A case head failure with plastic deformation is caused by too much pressure. In this specific instance, what is being shown is what a secondary explosive event would look like. The OP said that he used a powder charge that was much lower than normal, so this is not an over charge event. Also, when a case is loaded too many times, the failure mode is usually case mouth splitting, not a case head failure.
Improper headspace Only results in separation, if, full length resized too many times.... Loose headspace is manageable..
But.. Nuther Story...different event..
I do In fact believe that this lot of brass may be getting "long in the tooth" maybe even brittle...I show No Notes of it being annealed.. I checked that because I wondered what the result would be if the head inadvertently got Annealed!! But... Like you... I believe there was a Moment of fairly high pressure..
Beyond that... I'm betting that a case full of 748 under an even close to proper cast boolit, could Not cause such "flow".. I sure hope I would have noticed when I checked the case after charging if it was that much fuller than the rest!!! But.. I am Older... My eyes aint what they used to be.. ETC... Sure glad none of the pulled down and rechargeg cases acted up!!!
Again... My mind is racing, concerning annealed case heads!!!!

[TNsailorman]

I knew the S E E doubters would show up sooner or later. I have yet to see (pun intended) anything to refute that a very low charge of some powders cannot be ignited along the entire length of the powder charge if the charge is lying below the level of the primer itself. Folks use to call it an "overpressure" wave meaning the powder ignited aling the top of the entire length of the charge and then hit the base of the bullet and traveled back sending the pressure skyrocketing. Most of the burning seemed to occur from the front of the charge backwards. You had hot expanding gasses travel both ways and slamming into one another creating a trememndous pressure point where they met. I can't prove this in a laboratory setting myself but I seem to remember that H.P. White laboratory did some testing of this very thing many years ago(it may have been in the 60's). If I remember correctly (possible) they concluded that it was possible but rare. Anyway, the argument will go on forever it seems with neither of the parties willing to give an inch. makes for some interesting reading at times and sometimes just plain boring. james

[racepres]

^^^ But, but, but
What do you think would result if the head of a case was inadvertently Annealed????
Sure that these were Not... but... got my mind Buzzing!!!

Edit; To be Frank (hope he don't mind).. I have always believed that small charges of Ball powder could Only result in Low pressure, and certainly a Stuck Projectile.. like any other powder!
But... I am now rethinking that

[megasupermagnum]

I knew the S E E doubters would show up sooner or later. I have yet to see (pun intended) anything to refute that a very low charge of some powders cannot be ignited along the entire length of the powder charge if the charge is lying below the level of the primer itself. Folks use to call it an "overpressure" wave meaning the powder ignited aling the top of the entire length of the charge and then hit the base of the bullet and traveled back sending the pressure skyrocketing. Most of the burning seemed to occur from the front of the charge backwards. You had hot expanding gasses travel both ways and slamming into one another creating a trememndous pressure point where they met. I can't prove this in a laboratory setting myself but I seem to remember that H.P. White laboratory did some testing of this very thing many years ago(it may have been in the 60's). If I remember correctly (possible) they concluded that it was possible but rare. Anyway, the argument will go on forever it seems with neither of the parties willing to give an inch. makes for some interesting reading at times and sometimes just plain boring. james

Awful lot of speculation there nobody can prove. I'm willing to give an inch. I have the same opinion I have always had. Loads are pressure tested all the time, entire books are filled with the results. Show me a pressure test that resulted in a SEE. Nobody in all these years has come up with the goods. What else am I supposed to think?

[TNsailorman]

Awful lot of speculation your part also. But yours is a fair statement. But I can turn it around and ask you to show me a pistol or rifle that was blown up by a very low powder charge and explain to me how such a thing can happen. So far no one has been able to completely disprove S E E or for that matter completely prove how it works, if it works. But it is a matter of record that some complete destructions of both rifles and pistol have take place with very low powder charges, especially with certain powder. That is the reason most manuals warn the reader about loading charge of certain powders below the recommended start charge they list. 296 being one and H110 another. I can neither prove or disprove the phenomenium one way or the other and neither can you. Blindly stating that every blown firearm is a result of an overcharge when you have no way of knowing whether the case held an overcharge or not is just not being rational in my book. But, everyone has to make up their minds about this and you are perfectly welcome to your opinion as well as those who have the opposite oinion. james

[Recycled bullet]

Sharpen a paper clip to a needle point.

Bend it/ angle it at the tip, just long enough that it will pass through the fired cartridge case mouth.

Use the poker to find uneven brass near the case head and web, deep inside the fired cartridge. It will feel striated or lumpy if there is a problem, not smooth.

You will feel the vibration through the pick if the point passes over a rough surface.

You will feel for impending case head separations.

[TurnipEaterDown]

I had the luck of disassembling a round that would not fire, but nearly did, and would likely have taken the gun apart.

6 mm on a improved 280 Remington case w/ 20° shoulder -- basically a lengthened 243.
Case will hold 70 gr AA8700 ball powder under a 100 gr bullet.

I was doing development work, 80 gr bullets. Rem PSP, 51.5 gr H4831, 78% case volume is what my notes show. F215GM.

Trigger pulled, click no bang, waited a minute, extracted round, took it home, disassembled by pulling bullet w/ press and pliers (extend round through press opening, clamp on pliers, reverse ram).

Powder was packed in neck & shoulder so tight that I had to use a a small std screwdriver to pick it out chunk by chunk. Considerable amount of that powder which remained in the case was no longer black, it was straw colored. Primer was fired.

Pretty obvious what happened: Primer went off, scorched a bunch of powder, powder extinguished after sufficient pressure rise to compact much of the charge in the shoulder & neck.

Had it not extinguished, I have 0% doubt that I would have had a blown up gun. I do not believe that material in the shoulder / neck would have been anything but an obstruction, had that powder reignited / experienced a delayed burn.

30 Years, I still have that bag of pulldown components from that load. Still have the rifle, and it shot I think 19 antelope. I use slower powders and more case fill now.

I also had Similar happen on a 500 Linebaugh Long w/ a charge of WC1680, that was at / Just below "published" start. In this instance the round was primed w/ a F155 and the powder didn't come out of the case burnt looking, just in a packed lump behind the bullet which had to be driven backward out of the forcing cone.

Heavily deterred "Slow" powders at reduced case fill, in combination w/ large case volume to bore ratio, are in my mind something to very much stay away from.

[Recycled bullet]

You should be able to feelhttps://uploads.tapatalk-cdn.com/20230307/bcc890e54ccc1b14e97323c731ae1625.jpg the groove forming that eventually leads to this split you are having.

Discard all the brass with the groove it's expired.

[racepres]

You should be able to feelhttps://uploads.tapatalk-cdn.com/20230307/bcc890e54ccc1b14e97323c731ae1625.jpg the groove forming that eventually leads to this split you are having.

Discard all the brass with the groove it's expired.

Assuming Case Head separation caused all that???
Kinda like assuming Excess Headspace causes High Pressure..
I have witnessed case separation both of the head, and of the complete neck from the shoulder...Neither was My ctg. But.. the Report was decidedly Less, and no other cartridge damage nor evidence of Excess Pressure.
No My forensics tells me that that Tear was caused After the Main Event, by either the claw extractor/and or by beating the Case out of the Chamber.. And...yes again, all of that lot has been checked with a Bent Paperclip for incipient separation... None evident.
I do have a 300 Savage round I obtained used/unknown, that split half way around on my first firing...Obviously I did Not check that one. Since only halfway split, I can feel the stretched area with my paperclip...I keep it handy to use as a test for feel, when checking cases. When I fired that case.. the report was Less, and zero evidence of excessive heat nor pressure..
I guess I understand the reluctance to believe in such events...I was resistant also. But, remained open minded, because I refuse to Assume it was the Fault of the reloader every time I have heard of such events.. But... yes the reloader Is in Fact at fault for either a too large or a too small, charge weight... Human Nature dictates that for Most, "It can Not Happen to Me", and "it is Obviously Your Own Fault".. Which It Is... but, explanations are sometimes difficult to swallow..
Obvious to the Casual Observer, that this was a Pressure Event. And I am satisfied it was Not an Overcharge. To The Point that I am tempted to Purposely charge a Full Caseful with that powder and boolit, and light it off (remotely).. But...that will Not satisfy the Naysayers, No Matter the Outcome.
Especially those that are convinced that excess headspace causes Guns to Blow Up..

[waksupi]

That doesn't look like SEE to me.

[unique]

"Powder was packed in neck & shoulder so tight that I had to use a a small std screwdriver to pick it out chunk by chunk. Considerable amount of that powder which remained in the case was no longer black, it was straw colored. Primer was fired."

I have had something similar happen with BLC-2 in 30-06 with light load. Click then nothing...pulled cartridge and powder 'melted' into glob. The bullet was lodge in throat. Had that powder ignited I would have had a problem. Win748 is similar to BLC-2. Ball powders are not flexible.

[racepres]

That doesn't look like SEE to me.
By all means..what has your Experience Been??
Please do Not say headspace... I will explode!!!

[Recycled bullet]

Respectfully racepres I assume nothing.

I see a broken cartridge.

I hope you were not injured.

I hope your rifle is undamaged.

[megasupermagnum]

Here's the problem. There is a long list of things it could have been. You don't think it was headspace, and you don't think it was an overcharge. That's fair. That doesn't mean you just throw up your hands and claim it's from some obscure phenomenon that hasn't been repeated in a lab.

That's like saying you saw a giant hairy beast walking on 2 legs in Iowa. Black bears don't live there, so it must be sasquatch.

[dverna]

I do not reloaded enough CF rifle to have experienced something like this. I doubt more than 10k out of the 500k reloads I have under my belt. Plenty of light pistol loads but common opinion is that SEE is not possible with fast powders.

I do not worry about SEE in rifle cases as I never experiment with loads lighter than book starting loads.

Arguing about SEE is not new. But it would only matter if it occurred with a book load.

People might try things during shortages when they cannot get the proper powder but, in general, there is little reason to do so. In this case, the OP made an honest mistake and it resulted in a possible SEE. I do not know if a SEE happened but I presume using a published load is going to be safe.

[racepres]

Respectfully racepres I assume nothing.

I see a broken cartridge.

I hope you were not injured.

I hope your rifle is undamaged.
Nah...all good.. Thank goodness for strong Rifles for weak minds!!! LOL


Here's the problem. There is a long list of things it could have been. You don't think it was headspace, and you don't think it was an overcharge. That's fair. That doesn't mean you just throw up your hands and claim it's from some obscure phenomenon that hasn't been repeated in a lab.

That's like saying you saw a giant hairy beast walking on 2 legs in Iowa. Black bears don't live there, so it must be sasquatch.

The Thing is...I Know it was a Severe Under Charge.. Now What???


I do not reloaded enough CF rifle to have experienced something like this. I doubt more than 10k out of the 500k reloads I have under my belt. Plenty of light pistol loads but common opinion is that SEE is not possible with fast powders.

I do not worry about SEE in rifle cases as I never experiment with loads lighter than book starting loads.

Arguing about SEE is not new. But it would only matter if it occurred with a book load.

People might try things during shortages when they cannot get the proper powder but, in general, there is little reason to do so. In this case, the OP made an honest mistake and it resulted in a possible SEE. I do not know if a SEE happened but I presume using a published load is going to be safe.
It was 10grains Under the Start Load.. so was less than 50% of a 100% load density.. I also truly believe that if we Pay close attention, and stay with Published Data...All is Good
And... I surely do not be concerned if my Pistol/Shotgun powders are Low Density...Published loads Again!!!
By Now ...everyone has at least Heard, that lower than recommended loads of Ball Powder are Bad JuJu.. I concur!

[Larry Gibson]

It has all the elements of a classic SEE. An expanded primer pocket like that is proof, not speculation, of a high/excessive pressure event. In that cartridge 26 gr of 748 is less than 50% fill. Classic SEE, they do happen.

[Hannibal]

I'm hoping some additional photos will be posted simply so I can understand this better. After further explanation I think the case head damage was likely caused by the force required to open the bolt.

The split/cut in the side of the case is the thing in particular that I don't understand at this point in the discussion.

[super6]

Excuse me for not knowing what S.E.E means I am assuming It is detonation, That can not happen in a cartage Unless there is a deflaguration first, Other wise A detonation wood have blown you and your gun to pieces, And a run back and a shock wave is possible with deflaguration Think M80. A low powder charge is ripe for this. Just my 1 cent worth.

[racepres]

I'm hoping some additional photos will be posted simply so I can understand this better. After further explanation I think the case head damage was likely caused by the force required to open the bolt.

The split/cut in the side of the case is the thing in particular that I don't understand at this point in the discussion.
Yea... I understand that... it took a Club to open the Bolt!! The Mauser Extractor did indeed try to extract the round.. extractor is still good... jus no Case in the place for it to get ahold of !!
I drove the Case out with a Dowel..the dowel did Not push against the Mouth of the case... it pushed on what was left of the Web... The Lack of smoke/soot at that split tell me that tale.. ripped when extracting...any other splits in a fired case have Always been smoked quite Black, in and all around the "split"..
Maybe I get more pics later today...

[Larry Gibson]

How many cartridges had been fired prior to the SEE?

[racepres]

How many cartridges had been fired prior to the SEE?...
None, Just that one...Hard as it may be to believe..
Thinking about it...it is my custom to carry ammo Boolit Down, and the Mauser gets loaded Muzzle down.. I may have exacerbated the situation by inadvertently having the powder as far away from the primer as possible.. I did Not fire any more tho to quantify that!!! the remainder were pulled...and My Mistake was revealed!!
BTW I shoot out the back door, so My Bitter Half has heard at least her share of GunFire... she showed up in a Kinda hurry, saying it sure didn't Sound Right.. Most of the "noise" was right at the receiver...vs at the Muzzle.

[TurnipEaterDown]

Excuse me for not knowing what S.E.E means I am assuming It is detonation, That can not happen in a cartage Unless there is a deflaguration first, Other wise A detonation wood have blown you and your gun to pieces, And a run back and a shock wave is possible with deflaguration Think M80. A low powder charge is ripe for this. Just my 1 cent worth.

SEE = Secondary Explosion Effect.

To me, what I Nearly experienced, and related in earlier post in thread, is fairly well described by this nomenclature. "Secondary" being key to me.
Being convinced that on two occasions I had a circumstance occur, whereby if powder had remained near the ignition point and then completed rather than extinguishing after dwelling near the ignition point, "secondary" has relevance.

Powder must reach a temperature to ignite.
To reach specified temperature, a specific amount of energy must be input to raise a critical mass of the powder to the self sustaining combustion point (ignition).
This amount of energy varies w/ initial temperature, and other factors such as how much energy is wasted in things like moving the powder around the case and heating the case. Also, though not relevant directly to the powder, insufficient / borderline energy can be put into a primer to get rapid combustion of the primer compounds.
As the amount of powder is reduced in the case, combustion energy from the primer has an increasing number of 'places to go' rather than directly into powder grains to raise their temperature. Hence, reduce the powder, make it more difficult to ignite.

As the primer releases its energy (combustion) the powder is heated directly, and as the pressure is raised in the case (primer solids turning to gases and occupying more space) the gases in the case (residual air) raise in temperature simply by compression. Both of these effects initiate combustion of the powder in the case. To what extent which, I am betting on direct heating from primer combustion being dominant.

Every different thing that primer energy heats has a different temperature rise per unit mass, given a specified amount of energy absorbed. Specific Heat Capacity is what I remember the term is. As to where the powder lies on the relative scale, I have never looked, but I would bet a couple boxes of doughnuts that it is very much less than the brass of the case.

Powders using deterrents to slow initial burning rate (make them more "progressive") tend to increase energy input demand to initiate self sustaining combustion.

I really doubt that the conditions for a borderline ignition event would be easily replicated in a lab with enough control and repeatability to affordably understand it, or publish it. Maybe government funding of a grad student would afford that, but no reloading company is going to spend money on that. This is just a statement of speculation, but one from a person who has extensive lab experience, background in combustion, has been paid by the government for research, and has worked in a 'low profit margin' industry. The reloading company personnel who understand this loosely, as well as experienced people in the field will just say: '...don't do x,y,z...'

Whether the OP's event was SEE, or something else, or better described in other words, I think there is little proof.
However, part of the case head is disconnected from the rest of the cartridge, and it appears as if there is plastic flow around the interface to the rest of the original head. These are not signs of separation from thinning of the brass above the solid head from improper die set up or head space. It is pressure that flows brass like that, either to a point of direct separation or displacement such that the bolt rotation to open completely shears the chunk of head from the remainder of the case. Takes high pressure to do that.

Me, I would immediately discontinue the use of that load, and interpret what else to not think of doing in the future.

[405grain]

Well said. As a retired research and development engineer I concur with TurnipEaterDown's assessment. For the general public it is difficult to comprehend the power that's involved in a supersonic shock wave. Smokeless propellants are designed and intended for rapid combustion, not detonation. When an internal abnormality occurs that leads to the formation of a shock wave, this can cause an exponential pressure spike. As a mental experiment, lets examine what happens when an energetic material is detonated and creates a supersonic shock wave. C4 is an explosive material, not a flammable material like gun powder, but it will generate a shock wave upon detonation. Let's place a 1 pound blob of C4 on top of a stick that stands about 4 or 5 feet above the ground. Now let's place that stick about 10 feet away from a dump truck. When the C4 is detonated what happens to the truck? It gets messed up, that's what happens. Why did the truck get smashed up? Because the detonation of the explosive caused an expanding shock wave that compressed the air until it was harder than steel. Think about that: it made the air harder than steel.

This is clearly not what occurs inside a cartridge case, but is an example of how, if a shock wave is created it will set about an unfavorable chain of events, ie: rapidly increased rate of combustion with dramatic increase in pressure. It is not surprising that neither bullet or powder manufacturers don't have (or at least don't publish) test results that may have recorded a S.E.E. event. Why would they intentionally destroy their testing apparatus to create a load that is far outside any recommended loading applications? Remember "Absence of evidence is not evidence of absence". As far as getting full disclosure from ballistics labs, anyone care to outline the reason that Blue Dot is not recommended for the 41 magnum, or with 125 grain bullets in the 357 magnum? I know that this question is far off topic, but is does show that sometimes powder testing labs play their cards close to their vest. I think that the OP's under charge of a ball powder caused a flash over that resulted in the very rapid combustion of the powder charge, resulting in too high of a chamber pressure. If you think that there's no evidence for such an event, the OP put a photo of it in the first post. If the firearm was able to withstand the pressure generated, this is exactly what a secondary explosive event would look like. All are welcome to their opinions, and without laboratory testing the results will have to remain inconclusive. Outside of government funding for some possible military application, I can not see anyone investigating this phenomenon: it would cost money to destroy the equipment that labs would need for other purposes.

[unique]

"Powder was packed in neck & shoulder so tight that I had to use a a small std screwdriver to pick it out chunk by chunk. Considerable amount of that powder which remained in the case was no longer black, it was straw colored. Primer was fired."

I like this line so I will stay with it...nitrocellulose is straw color. Ball powder has a deterrent coating on the outside of each ball of powder as well as graphite (the back). Ball shape burns digressive and only way to make it progressive is to slow the initial burn rate by adding deterrent coating. Anyway, if the powder is straw color then that means the powder burn rate is likely faster since deterrent coating is at least partially burned off. I believe a shock wave may be part of the equation...regardless ball powders are not flexible and reduced loads are inviting trouble.

Relative to shock wave, it you take a primed only case and fire it in a rifle, a shock wave will travel down the barrel then reflect off the end of the barrel and return to starting point...this is not conjecture but wave theory.

So what could have possibly happened: primer fired and pushed bullet and powder out of case; powder did start to burn but volume increase from movement causes reduce pressure; powder burns slower but now is packed in bore and bullet lodged in bore; powder movement stopped by bullet lodged so powder begins to burn faster (increasing pressure) and with a reduced deterrent coating even faster and with possibly return shock wave super duper fast.

[racepres]

"Powder was packed in neck & shoulder so tight that I had to use a a small std screwdriver to pick it out chunk by chunk. Considerable amount of that powder which remained in the case was no longer black, it was straw colored. Primer was fired."

I like this line so I will stay with it...nitrocellulose is straw color. Ball powder has a deterrent coating on the outside of each ball of powder as well as graphite (the back). Ball shape burns digressive and only way to make it progressive is to slow the initial burn rate by adding deterrent coating. Anyway, if the powder is straw color then that means the powder burn rate is likely faster since deterrent coating is at least partially burned off. I believe a shock wave may be part of the equation...regardless ball powders are not flexible and reduced loads are inviting trouble.

Relative to shock wave, it you take a primed only case and fire it in a rifle, a shock wave will travel down the barrel then reflect off the end of the barrel and return to starting point...this is not conjecture but wave theory.

So what could have possibly happened: primer fired and pushed bullet and powder out of case; powder did start to burn but volume increase from movement causes reduce pressure; powder burns slower but now is packed in bore and bullet lodged in bore; powder movement stopped by bullet lodged so powder begins to burn faster (increasing pressure) and with a reduced deterrent coating even faster and with possibly return shock wave super duper fast.
Assuming the Boolit did Not exit!!! What if it Did escape the bore?? Course... It may have been ejaculated...(always wondered how to use that term) when pressure went thru the roof....

[MT Gianni]

Winchester recommends 46 gr as a starting load with a 170 gr jacketed bullet with 308, and WW 748. How did you arrive at your 36 gr load?

[racepres]

Winchester recommends 46 gr as a starting load with a 170 gr jacketed bullet with 308, and WW 748. How did you arrive at your 36 gr load?

8X57,, 170 Lead...Older Lyman Cast Handbook

BTW At 36 gr the load is Light, the mouth don't seal, as evidenced by too much black soot.. I will be Upping that loading...Next time!
Tho, Mine is a Plain Based Boolit, and I do Not desire more FPS...So, prolly stick with Unique and/or 2400, but my stash of 2400 is dangerously low!!!

[waksupi]

By all means..what has your Experience Been??
Please do Not say headspace... I will explode!!!

SEE will usually result in a blown receiver or barrel.

[racepres]

SEE will usually result in a blown receiver or barrel.

You gots no Large Ring Mausers huh?? Never even heard tell of one Blown Up

[Hannibal]

You can find plenty with a few minutes of searching the internet.

Not everything one sees on the internet is true but I know an overpressure event when I see one.

[racepres]

You can find plenty with a few minutes of searching the internet.

Not everything one sees on the internet is true but I know an overpressure event when I see one.

All Good... But... I only find small ring Mausers Blown Up... Link Please...

[beemer]

Years back I was shooting a 91/30 and got tired of the corrosive ammo and the recoil. I was working up a lighter load with Win 760. I wish I had kept the info as well as the case and bullet. Anyway I loaded five rounds and fired the first, it was a a click bang. The second one the primer went off and nothing, I stopped and walked away. The bullet never left the case and the powder was glob that had to be dug out of the case. Knowing what I know now the first shot would have scared me. I don't use light loads with ball powder, good stuff but it has it's place.

As we get older we learn, anything don't feel, look, or sound right we investigate and wear safety glasses. But the best we can do something will eventually sneak up on us. I am thankful no one was hurt.

I saw a really bad over pressure event in a Swedish Mauser. The case had been formed from I believe a military 30-06 case and had been overcharged with 4320 and a 140 gr bullet of some type. The bolt had to be hammered open, the primer was gone, primer pocket was enlarged and the case looked like it had a belt on it. Brass extrudes at what, 75,000 psi ? The rifle survived apparently intact as the guy is still shooting it years later. He threw the case away but I dug it out and kept it, I look at it occasionally.

I believe it was H.P. White Labs that did a experiment with SEE. I have the report here somewhere. The rifle was a 6.5 X 55 Swed Mauser and lighter loads of slow burning powder. The long rough throat let the bullet start, the pressure dropped and the bullet stopped creating a bore obstruction. The long bearing surface of the bullet played a part. The pressure trace showed a rise then a drop and a spike. I need to look that up.

[waksupi]

All Good... But... I only find small ring Mausers Blown Up... Link Please...

Spoon feed yourself.

[racepres]

Spoon feed yourself.
Well Put... Google is your Friend... Not Mine... I care less... I still havent seen a Large Ring Mauser Blown Up.. So, Will Remain Ignorant!!
Thanks

[405grain]

I don't think there's any gun ever made that can't be blown up. However, when it comes to Mauser's that have been damaged by dumbness, the small ring Mauser's outnumber large rings by far. If you respect the strength of the action and use cartridges in the pressure range that it was designed, for small rings are great. Hordes of large ring actions have been chambered for magnum cartridges, so you're a lot less likely to see a large ring come apart than a small ring. Most of the photos that I've seen of Darwin Award small rings have been of Swedish Mausers. I think the problem here was that people thought that these actions were made of "special steel", so they could take the pressure. Yes, the composition of the metal might have been better, but those actions were designed for use with the 6.5x55 Mauser. I wouldn't exactly consider the military load 6.5x55 a high pressure round, at least not compared to many of today's modern cartridges. Bubba can turn any gun into a pinata, but I think its a lot more likely with a small ring than a large ring.

[racepres]

OK. I understand all that and how it's supposed to function. I was hoping someone has a barrel outside the action or a cut-away view so I can see the unsupported area that's being discussed.

I appreciate your help guys. I'm always happy when I can increase my knowledge and understanding.
Got a couple poor pics... will try to get a shot of Why the 98 won/cant discharge out of battery, but, a video would be best for that.. HTH
311419
311420

[racepres]

@Hannibal
Here is a couple shots with my attempt at explanation...
311421
First is the cocking piece as it is without bolt in battery.. Note the abutment in front of the Nose...would halt forward (up) motion f cocking piece which is directly attached to the Firing pin on other end of bolt..
311422
This is what it would look like if Bolt was about halfway closed.. either the motion of the Cocking piece/firing pin would be interrupted... or More likely, the "ramp" would force the bolt fully closed..
so that it would look like this
311428
Cocking piece/firing pin all the way forward, and as be seen... the bolt handle Must be all the way into locked/firing position.

HTH Somewhat

[Kestrel4k]

Starting with facts but then going into my opinion;


W748: ball powder, heavy deterrent coating, hard to ignite. Checking a few sources briefly, all suggest a magnum primer.
Significant undercharge in this specific situation; the resulting lower initial pressure makes complete ignition of the charge more difficult.
Boolet pops out of case, lodges in bore just ahead of the case.
Firmly constrained volume now permits full ignition of the remaining charge; burn rate of powder increases with increasing pressure.
Obstructed bore, overpressure event.

I have done much with reduced loads, but never with ball powders for this very reason.

I would very much recommend reading the following brief thread, for a greater understanding of the limitations of W748:
http://forums.thecmp.org/showthread.php?t=236414

Edit:
Note posts #7 and #9; in particular, the problem load in that thread had only 70% loading density.
A rough QuickLoad check indicates a 60% loading density for this erroneous load.

[M-Tecs]

Starting with facts but then going into my opinion;


W748: ball powder, heavy deterrent coating, hard to ignite. Checking a few sources briefly, all suggest a magnum primer.
Significant undercharge; the resulting lower initial pressure makes complete ignition of the charge more difficult.
Boolet pops out of case, lodges in bore just ahead of the case.
Firmly contstrained volume now permits full ignition of the remaining charge; burn rate of powder increases with increasing pressure.
Obstructed bore, overpressure event.

I have done much with reduced loads, but never with ball powders for this very reason.

I would very much recommend reading the following brief thread, for a greater understanding of the limitations of W748:
http://forums.thecmp.org/showthread.php?t=236414
Note posts #7 and #9 in particular.

That would be the most likely chain of events.

[racepres]

Starting with facts but then going into my opinion;


W748: ball powder, heavy deterrent coating, hard to ignite. Checking a few sources briefly, all suggest a magnum primer.
Significant undercharge; the resulting lower initial pressure makes complete ignition of the charge more difficult.
Boolet pops out of case, lodges in bore just ahead of the case.
Firmly contstrained volume now permits full ignition of the remaining charge; burn rate of powder increases with increasing pressure.
Obstructed bore, overpressure event.

I have done much with reduced loads, but never with ball powders for this very reason.

I would very much recommend reading the following brief thread, for a greater understanding of the limitations of W748:
http://forums.thecmp.org/showthread.php?t=236414
Note posts #7 and #9; in particular, the problem load in that thread had only 70% loading density.
Agree with all except the % of load was well under 70%... more closer to 50%
Note.. This was Purely Operator Error... too Light a Charge for the powder in use..stated in very first post. Just a mistake.. Not the Intended loading...
Now a couple more shots just to get feel for the What I believe the case is telling us..
311429
this is where the case was most probably positioned in relation to Bolt at time of firing... the missing rim would be under the extractor in this example...purely Fictional... but my best guess...
311430
This is where I am thinking the extractor tore the Rim Off of the slightly damaged case (yea some stab at Humor)
311431

From this angle i would Note that the Neck and front of shoulder are Not that far Oversize as compared to what I been Shooting!!!
And Finally...No the Projectile was Not in the bore Post Mortem...

[Kestrel4k]

Are magnum primers being used ?

[Cap'n Morgan]

I had the same experience with a Swedish Mauser 96 many years ago. You can read about it here:

https://castboolits.gunloads.com/showthread.php?31989-6-5X55-in-a-Krag

I was using the ammo, with the same head stamp as Dutchman posted in the thread.

[Hannibal]

Agree with all except the % of load was well under 70%... more closer to 50%
Note.. This was Purely Operator Error... too Light a Charge for the powder in use..stated in very first post. Just a mistake.. Not the Intended loading...
Now a couple more shots just to get feel for the What I believe the case is telling us..
311429
this is where the case was most probably positioned in relation to Bolt at time of firing... the missing rim would be under the extractor in this example...purely Fictional... but my best guess...
311430
This is where I am thinking the extractor tore the Rim Off of the slightly damaged case (yea some stab at Humor)
311431

From this angle i would Note that the Neck and front of shoulder are Not that far Oversize as compared to what I been Shooting!!!
And Finally...No the Projectile was Not in the bore Post Mortem...

I appreciate your follow-up on the events and the pictures posted. What I failed to understand in your first post was that I didn't understand the problem that you had when you extracted the case. I appreciate what you've posted as follow-up.

So far as the destruction of large ring Mausers I cannot find an example where the action can be unmistakably identified as a large ring Mauser, so I've not posted what I've found. They are definitely robust but I'd not want to bet it's not possible to destroy one.

And as for whether the actual cause was a S.E.E. event or not I'll leave that discussion to others more versed in such things than myself. Obviously the problem was a combination of a very light load and ball powder which you plainly stated from the outset.

Anyway, glad you and the rifle escaped unscathed. And thanks for starting the thread. It's been a very interesting discussion and food for thought.

[racepres]

Are magnum primers being used ?

Yes...as a Matter of fact...tho I was sure they may Not be necessary.,.. I pretty much use Only Magnum Primers with Ball Powders...except AA powders, just because when I first discovered Accurate powders they specifically stated that Magnum Primers were Not a Necessity, nor recommended, with their product..
Remington 9-1/2's

[Larry Gibson]

Starting with facts but then going into my opinion;


W748: ball powder, heavy deterrent coating, hard to ignite. Checking a few sources briefly, all suggest a magnum primer.
Significant undercharge in this specific situation; the resulting lower initial pressure makes complete ignition of the charge more difficult.
Boolet pops out of case, lodges in bore just ahead of the case.
Firmly constrained volume now permits full ignition of the remaining charge; burn rate of powder increases with increasing pressure.
Obstructed bore, overpressure event.

I have done much with reduced loads, but never with ball powders for this very reason.

I would very much recommend reading the following brief thread, for a greater understanding of the limitations of W748:
http://forums.thecmp.org/showthread.php?t=236414

Edit:
Note posts #7 and #9; in particular, the problem load in that thread had only 70% loading density. It also is more tnan like what occured in the OPs "event".
A rough QuickLoad check indicates a 60% loading density for this erroneous load.

This is essentially the correct chain of events for an S.E.E. This what most likely actually occurred in the OPs "event".

BTW; smokeless powders in cartridges do not detonate. Also, the "wave theory" has never been proven. The above series of events have been proven to be the cause of S.E.E. and have readily been produced with psi measured since the mid '80s.

[unique]

This is essentially the correct chain of events for an S.E.E. This what most likely actually occurred in the OPs "event".

BTW; smokeless powders in cartridges do not detonate. Also, the "wave theory" has never been proven. The above series of events have been proven to be the cause of S.E.E. and have readily been produced with psi measured since the mid '80s.

I agree most powders would be difficult if not impossible to detonate. However, high NG powders like Bullseye will most certainly detonate under the right circumstance.

Relative to 'wave theory', just to be clear, I think most reasonable individuals would agree that wave theory as a science is well established. Norma/Bofors writeup on powder discusses the 'see' phenomenon and mentions pressure wave as a factor. I mentioned this earlier in this thread; when a cartridge fires, or for that matter a primer only, a pressure wave travels up the barrel, reflects off the end of the barrel (that is what waves do when there is impedance discontinuity) and travel back to source. It isn't all that difficult to see (no pun intended) how a pressure wave could make a bad situation (plugged bore and smoldering powder) into a catastrophic situation. The "wave theory" has never been disproven.

[GregLaROCHE]

Is there any chance that case got annealed completely, including the case head?

[racepres]

I agree most powders would be difficult if not impossible to detonate. However, high NG powders like Bullseye will most certainly detonate under the right circumstance.

Relative to 'wave theory', just to be clear, I think most reasonable individuals would agree that wave theory as a science is well established. Norma/Bofors writeup on powder discusses the 'see' phenomenon and mentions pressure wave as a factor. I mentioned this earlier in this thread; when a cartridge fires, or for that matter a primer only, a pressure wave travels up the barrel, reflects off the end of the barrel (that is what waves do when there is impedance discontinuity) and travel back to source. It isn't all that difficult to see (no pun intended) how a pressure wave could make a bad situation (plugged bore and smoldering powder) into a catastrophic situation. The "wave theory" has never been disproven.
I studied Exhaust system for internal combustion engines diligently.. my quection in this regard is, "how did yer Wave get past the Boolit to reach the Muzzle??" if it was contained by the case my input would be that the wave sure was a Short one!!! But.. I did Not study Ballistics!!


Is there any chance that case got annealed completely, including the case head?

I brought this up previously.. and that kind of thing is as Possible as an entire batch being Undercharged... obviously.. would Less Powder cause such an increase in pressure, yet the rest of the lot (was only 20 rounds) Not be affected when charged to the proper (10.0 full grains) ?? Meaning only one case was improperly annealed???? again.. I surely do Not know that.. all I can say is.. I do Not have a record of Annealing that lot, and I usually keep track, And, based on the considerable effort to raise the bolt and then Tear the rim like it did.. just how soft could that case have been??

[Recycled bullet]

You shot the piston out as the head gasket failed.

[racepres]

You shot the piston out as the head gasket failed.

Yea... I buy that.. especially if you could get enough slow powder in the case to create an overpressure purposely..
In this case... I would say this Pressure event May/Might have been caused by??? Some force that I do Not understand, that can make a Small Charge create More Pressure than an Overcharge could have!! Perhaps (in theory anyway) assisted/influenced by the projectile becoming an obstruction at some point... Certainly at some later point, the Pressure was enough to Ejaculate the Projectile..
In the Piston head gasket scenario... The Projectile/piston, would Not necessarily have cleared the cylinder... It don't in any of the Engines I am aware of...Even utilizing Nitro Methane... Now we getting outside the scope of Ballistics..so if you (RecycledBullet) want to discuss some of the Stuff I have learned about IC circumstance..I am available certainly.. Even PM me..

[Recycled bullet]

Guns and bullets are my favorite engines.

[Recycled bullet]

I think it's just absolutely wild the ride we send the bullets on.

The bullet gets forcibly threaded in the barrels rifling twist under pressure of many tons and still can be shot safely and accurately and cleanly and very fast.

I am just absolutely amazed that it is even possible to do this with home made powder coated bullets.

When I fix or cut new threads in metal in the shop there's the back and forth, clean and lube and remove chips, back and forth until it's nice and usable.

[Recycled bullet]

Maybe you need faster burn rate quickness rifle gun powders for safety with reduced loads.

3031 and 4227 have been very reasonable and predictable for me in 308 and 30-06.

[racepres]

Maybe you need faster burn rate quickness rifle gun powders for safety with reduced loads.

3031 and 4227 have been very reasonable and predictable for me in 308 and 30-06.
You sir are absolutely correct... this was Not intentionally a reduced load...it was supposed to be a book starting load... Operator Error is the root cause of the entire event, and this aftermath as well!!!
I'm beginning to believe I may should have kept this whole mess to myself, as I did Not intend to cause Drama... My Intent was to warn folks to remain diligent in your reloading procedures...What I did Not realize is that I may have caused people to feel somehow threatened, or even accused!!! Accidents Happen, be Careful Out There.

[Recycled bullet]

You don't have any control over the thoughts or actions of others. If someone else is some how triggered by your sharing your thoughts or opinions or actions that's on them, that's not on you.

If I did not want to read your post I would just look some place else.

Thanks for sharing, that I may learn from what happened to you, to try to avoid that happening to me.

[Larry Gibson]

I agree most powders would be difficult if not impossible to detonate. However, high NG powders like Bullseye will most certainly detonate under the right circumstance.

Relative to 'wave theory', just to be clear, I think most reasonable individuals would agree that wave theory as a science is well established. Norma/Bofors writeup on powder discusses the 'see' phenomenon and mentions pressure wave as a factor. I mentioned this earlier in this thread; when a cartridge fires, or for that matter a primer only, a pressure wave travels up the barrel, reflects off the end of the barrel (that is what waves do when there is impedance discontinuity) and travel back to source. It isn't all that difficult to see (no pun intended) how a pressure wave could make a bad situation (plugged bore and smoldering powder) into a catastrophic situation. The "wave theory" has never been disproven.

As I stated in cartridges smokeless powders do not detonate, that includes Bullseye. In "special circumstances" some do but not in cartridges.

The "wave theory" causing hign pressure excursions/detonations in cartridges is just a theory which has never been proven. The Norma/Bofors writeup was simply that, a writeup based on assumptions that have since been disproven when the real cause of S.E.E was discovered and easily replicated, I.E. proven. I'm not saying the wave theory is incorrect in theory but as it relates to a high pressure/S.E.E. excursion in a cartridge it is incorrect.

[Larry Gibson]

You sir are absolutely correct... this was Not intentionally a reduced load...it was supposed to be a book starting load... Operator Error is the root cause of the entire event, and this aftermath as well!!!
I'm beginning to believe I may should have kept this whole mess to myself, as I did Not intend to cause Drama... My Intent was to warn folks to remain diligent in your reloading procedures...What I did Not realize is that I may have caused people to feel somehow threatened, or even accused!!! Accidents Happen, be Careful Out There.

I appreciate you bring this incident to the forum. I also appreciate your honesty in reporting it and accepting your own responsibility in this incident. Your warning is well taken and should be listened to by others. We all can make mistakes and sometimes we get away with them. We should, hopefully, learn from not only others mistakes but our own also.

Thanks again,

[TNsailorman]

I totally agree with Larry on this. If we don't admit our mistakes, we are doomed to repeat them. If we care about the people we are around, we need to share our mistakes with them and maybe, just maybe, we can save them some grief or injury. No need for to feel bad or apologise. james

[Hannibal]

You sir are absolutely correct... this was Not intentionally a reduced load...it was supposed to be a book starting load... Operator Error is the root cause of the entire event, and this aftermath as well!!!
I'm beginning to believe I may should have kept this whole mess to myself, as I did Not intend to cause Drama... My Intent was to warn folks to remain diligent in your reloading procedures...What I did Not realize is that I may have caused people to feel somehow threatened, or even accused!!! Accidents Happen, be Careful Out There.

As others have posted I'm glad that you started this thread. No one ever learns anything if everything goes perfectly. Mistakes are how we learn where the limits are and the truly smart ones will learn from your experience.

Again, thanks to you.

[racepres]

Thanks you Guys... I am Not Butt Hurt anymore!!! LOL
I really did want to share in hopes this is Not repeated...especially by Me of course!!!!!

[unique]

I studied Exhaust system for internal combustion engines diligently.. my quection in this regard is, "how did yer Wave get past the Boolit to reach the Muzzle??" if it was contained by the case my input would be that the wave sure was a Short one!!! But.. I did Not study Ballistics!!



Ah, a great question. The wave is not traveling through the bore. The wave is traveling through the metal of the barrel. It is well known that a barrel vibrates when fired. Very similar to taking a piece of rope and giving it a good snap.

That vibration is a wave traveling the length of the barrel. This is why barrel bedding makes a difference. If you made the barrel really long the wave would die out before reflecting (again think about a really long rope which you snap). There are more complexities to this as you can get a wave reflection right near the cartridge as well but trying to keep this simple.

Anyway, a wave will reflect off the end of barrel and back to the source; this is not conjecture but well established. Now a partial of that wave passes through the metal bullet to the powder packed next to the bullet and still smoldering. Is this when 'see' happens? Maybe.

The possibility of wave reflection near the cartridge exists and would likely involve a much stronger pressure wave so maybe 'see' happens under this condition. (I would explain but that would take couple more paragraphs of wave transmission theory and everyone will glaze over if they haven't already).

Can a 'see' happen without a pressure wave? Maybe. I wouldn't rule out any of these possibilities as there are a lot of nuances that occur when cartridge is fired. They happen whether we recognize them or not.

[racepres]

Ah, a great question. The wave is not traveling through the bore. The wave is traveling through the metal of the barrel. It is well known that a barrel vibrates when fired. Very similar to taking a piece of rope and giving it a good snap.

That vibration is a wave traveling the length of the barrel. This is why barrel bedding makes a difference. If you made the barrel really long the wave would die out before reflecting (again think about a really long rope which you snap). There are more complexities to this as you can get a wave reflection right near the cartridge as well but trying to keep this simple.

Anyway, a wave will reflect off the end of barrel and back to the source; this is not conjecture but well established. Now a partial of that wave passes through the metal bullet to the powder packed next to the bullet and still smoldering. Is this when 'see' happens? Maybe.

The possibility of wave reflection near the cartridge exists and would likely involve a much stronger pressure wave so maybe 'see' happens under this condition. (I would explain but that would take couple more paragraphs of wave transmission theory and everyone will glaze over if they haven't already).

Can a 'see' happen without a pressure wave? Maybe. I wouldn't rule out any of these possibilities as there are a lot of nuances that occur when cartridge is fired. They happen whether we recognize them or not.

Pretty Complicated...Extremely hard to Verify and/or Quantify... With IC Exhaust...testing the Theory is King!!! No Worky??? No Likey!!!!

[super6]

I appreciate your humor, No worky No likey. LoL. I will use those terms again.

[unique]

Pretty Complicated...Extremely hard to Verify and/or Quantify... With IC Exhaust...testing the Theory is King!!! No Worky??? No Likey!!!!

Well I now better understand the root of your difficulties.

[Hannibal]

Well I now better understand the root of your difficulties.

Not sure what this means?

I try things for myself. If they don't work for me then I don't keep trying the same thing and expect the results to change.

No worky no likey. Sums it up well with a bit of humor added.

You no likey?

[racepres]

Well I now better understand the root of your difficulties.

No, You would need to see the Pile of Exhaust systems under my bench, to really understand!!!

[Shiloh]

Was gonna put this under case forming...But... Not Funny
documented to my satisfaction. I inadvertently put 26 grains of W748 instead of 36gr. into the 8X57 with 170gr Boolit
Double checked the charge in fact... physically, Not the Book ... Obviously
If yer gonna be Dumb...ya better be Tough...Or, Use a 98 Mauser.. Only My Pride, and Confidence in my Old Feeble Mind, were Shaken....Oh...And Nerves!!!!
Only thing I can come up with is S.E.E. Powder was definitely W748...charge was double Checked (even if Wrong).. old Mauser is Not any Worse for Wear!!!!
I never had anything like that, and been reloading since 1979 or so...
Be Careful You Old Farts!!!!... (maybe younger guys too)
Almost too embarrassing to Share... But... gettin old is about Sharing...
311302

Your fortunate it was a Mauser.
My guess is this was a good education for you. Stay safe.

Shiloh