Blew up my 629 today..embarrassed

[Calliope]

Glad the OP is OK and thanks for posting.

I used Titegroup for many years in my IHMSA Field Pistol loads, but I always charge 50 cases at a time and inspect them in a loading block.

One reason I've avoided progressive presses is that it's too easy to seat a bullet without seeing the powder charge.

I have to see that powder charge before I seat a bullet.

 

[fredj338]

I don't understand the thinking behind using such small charges of fast burning powders in such large cases. The potential for a catastrophic double-charge is too great.

Ya want light loads , use .44 Special or Russian brass.

If ya single charge your cases , do a block of 25 or so and visually compare powder levels.

A double or triple charged case becomes obvious.

TG in the 45acp case is hard to see a double. I shy away from & urge noobs to as well, any powder that won't fill a case 1/2 full. Then a double, or just as bad, a squib, is easily seen.

 

[scooter123]

IMO you have NOT found the cause of your mishap. Consider the change in case volume caused by those 3 small particles of corn media. I would expect that it's less than about 3% of the total available case volume.

The following is a gross over simplification because it's been over 40 years since I took Differential Equations but if you assume an infinitesimal slice of time it should be valid. That is Boyles Law states that in a change in volume relationship P1xV1=P2xV2. So assume that P1 = 30,000 PSI, a pressure distinctly on the high side for a near starting charge as you stated you were using. To make math real simple we will assume V1 = 100 and V2 is 5% lower at 95. So the effect on pressure of that reduced volume versus the ideal volume will equal 30,000 X (100/95) or 31,579 psi.

Now, consider the effect of doubling your powder charge. If we assume that the powder doesn't get pushed into Detonation the result should behave in a pretty linear fashion. So, best case you double the pressure to 60,000 psi. Unfortunately "faster" gunpowders tend to behave more like black powder and with any ignition process when the pressure and temperature reach a specific point that ignition process can be tipped over the edge from Burning into Detonating. In your case I suspect that is what took place.

 

[jeffreybehr]

Dutch, I too am sorry to read of your kaboom and am glad you're OK.

What this reinforces for me is reloading rule #1 which includes the three most-important parts of the reloading process--concentration, concentration, and concentration. Surely you didn't see this double charge while you were reloading, yes? Which means maybe that you weren't concentrating on your reloading...or--HORRORS--you don't look at EVERY powderdrop to see what's in the case.

And, same as others, and I've written this before, I simply don't use powder charges that can double- or triple-fill the case. Worst case for me is using a powder-and-weight combination that can be dispensed into the case but that the bullet won't seat over.

Again, I'm really glad that you're OK. Maybe we all learned something from your misfortune.

 

[Culina]

deleting my comment since I just noticed someone resurrected a necro-post

 

[dutch686]

Scooter 123 you may be right. I am not a math guy so I have to preface what I say with a maybe or "to the best of my knowledge". Thank you for the information.

 

[dutch686]

Scooter 123 you may be right. I am not a math guy so I have to preface what I say with a maybe or "to the best of my knowledge". Thank you for the information.


And just so the topic doesn't get too far off track. I didn't have a double charge of titegroup. That was the disconcerting dilemma of the accident. I was using a charge just above the minimum charge.

Thanks all for the well wishes everyone.

 

[fredj338]

Scooter 123 you may be right. I am not a math guy so I have to preface what I say with a maybe or "to the best of my knowledge". Thank you for the information.


And just so the topic doesn't get too far off track. I didn't have a double charge of titegroup. That was the disconcerting dilemma of the accident. I was using a charge just above the minimum charge.

Thanks all for the well wishes everyone.

After the fact, how can you be sure there was no double charge? People make mistakes, equip can malfunction??

 

[dutch686]

As I pulled the components apart I weighed each powder charge. No double charges

 

[jeffreybehr]

As I pulled the components apart I weighed each powder charge. No double charges

How can you pull the components of a fired cartridge apart?

 

[dutch686]

I didn't I pulled apart the remaining cartridges I had loaded. I agree it would be hard to pull apart and measure the fired cartridges.

I know it's a long thread, but go back and read it. That way you won't have to ask questions like this.

Pulling apart fired cartridges, smh

 

[dmar]

This may rate up there as one of the great unsolved mysteries; who killed Kennedy, who/what made Stonehenge, is global warming real, etc. Truth is, you probably will never know. I really don't think it was a few kernels of corn cob that did it. Somehow, you overcharged a round. God knows, it happens.

Also, as an off topic question that I've had over the two years since reading this post, do you own another 686? If not, have you considered changing your screen name...? Seriously, I've had this question since I first read your post.

And yes, I'm very glad you didn't get hurt, and I'm thankful that you shared your story. It's good for all of us re-loaders to be reminded of what could happen to us...

 

[nagant]

thanks for posting this. Can't imaging what you went thru! I weigh my finished rounds and now have even more incentive!

 

[novalty]

thanks for posting this. Can't imaging what you went thru! I weigh my finished rounds and now have even more incentive!

Do NOT go by finished round weight to determine if you have overcharged a case. There are too many other variables to rule out and overcharge. Case weight and bullets weight alone can get you a wide variance from round to round. If you think you overcharged, then you need to pull the round apart.

 

[fredj338]

How can you pull the components of a fired cartridge apart?

Bullet puller??

 

[Rick_A]

I think the biggest mistake a reloader can make is to assume an accident was not their fault.

I at least double check my charges but will never as foolish to assume that I can't make a mistake. I will continue to do my best to avoid one.

 

[scooter123]

Dutch, based on the results I cannot see any other cause than a double or triple charge. Unfortunately all it takes to produce a double charge is just a moments distraction at the wrong moment. Even waving off a pesky mosquito that snuck in through an open door could have you forget to rotate a turret/progressive press and drop two charges into one single case. If you are single staging you could pick up that charged case you set down to wave off that bug and then pick it up again to charge it a second time. And unfortunately a revolver case is deep enough that a double charge of a low volume powder such as Titegroup wouldn't be noticeable at a casual glance.

This potential problem area is one reason why I still single stage all of my ammunition. Because it allows me to put every charged case into a tray specifically so I can take an LED penlight and look into every single case in that tray. Only after I have done that check two separate times do I start placing bullets on the charged cases.

 

[rsrocket1]

IF you had 8.7g Titegroup in a case that had 0.3" taken up by other incompressible stuff, you could reach a peak pressure of 70,000 psi. Never having used corn cob, is it anywhere near as solid as walnut shells?

If you still have those cartridges loaded from when you had the kaboom, I would pull all of them apart and redo them. You already found one empty and one nearly double charge and you have evidence of trapped media that may be in other cases. You could salvage almost all the stuff you pull apart and you would be sure of the loads this time. With the stuff remaining, you'll never be sure.

 

[nagant]

I pulled 2 bullets, both were 6 grs over and both were cast bullets that were heavy. I am loading 100 rds a week or so with winchester cases the same primers. i charge and seat one at a time. weighing isn't a big deal, i got time.

 

[rwsmith]

Please don't discourage.....

Please don't discourage here for people admitting their mistakes. I want to hear about these because it helps to keep me on my toes.