Kaboom today

[ConcernedCitizen]

One other thought about weak crimps...

In addition to bullet setback, there's also the possibility of inertia driving the bullet forward into the lands, just like a kinetic bullet puller.

I don't know which situation would cause the most pressure, but it's something to think about.

 

[KaniksuKidd]

The unfired bullet setback is what bothers me. It can happen in the magazine from recoil if not properly crimped and could have caused setback and overpressure on the case that exploded, but very rare to see something like that.

Proper crimp for semi-auto pistol ammo involves using a taper crimp die as the 4th step in ammo preparation. This die squeezes the entire case rim down on the bullet. I have never experienced any bullet setback on a round that has been taper crimped. A roll crimp can be applied to a bullet that has a cannelure but I taper crimp these rounds too. Its just a better way to go.

 

[salmon creek gary]

I shivered a bit while reading the OP.

Just last week, I was at SafeFire when much the same thing happened to my M&P Shield 9mm while firing some commercial reloads.

As the echoes of my "OS!" died away, I took a shaky inventory. Two eyes, check. Ten fingers, check. No visible blood, check. No pain, check. Shield, intact - um, hold on there, seems to be a stovepipe in the ejection port and there's just a metal sleeve hanging where the magazine ought to be. Testing my (thankfully still good) vision, I found the guts of the mag & three live rounds on the bench in front of me. The heel plate was 5 feet downrange. That stovepipe casing, on examination, was blown out just above the base. It looked like a twin to P7id10T's blow-out.

The range officer & I took inventory all over again, slowly. He spotted some sort of white soot on my eye protection (easily wiped off), but nothing else amiss. With no immediate cause for alarm, we then examined the Shield. The frame (in spite of being tupperware) was undamaged, the bore was clear, and the mag shell was easy to remove. A little bit of debris on the feed ramp was easy to brush away, and the slide still worked smoothly. Using a good magazine, I was able to chamber and eject rounds normally.

After regaining ownership of my knees and respiration, I continued my range session with different ammo and no further incidents. Oddly enough, though, none of my pistols seemed to group worth a dang the rest of the afternoon.

 

[PNWguy]

Glad to hear that you are OK and the gun appears OK.

I've only been reloading a few years and got into it when I got into competition shooting. I like to fine tune my ammo for the particular gun and develop specific loads for my 10mm for woods carry.

I have had a few incidents of rounds not functioning due to newbie mistakes, but I am pretty OCD when it comes to powder levels and haven't had any kabooms. I use a Lee single-stage and still double-check powder levels for every tray of filled cases.

Closest I came was loading up a batch of .40 S&W match loads and accidently loaded them to 10mm match load specs.

Fortunately, 10mm match load powder levels are still below .40 S&W max powder levels, and I detected the error before the rounds ever left the reloading room, so no big deal. Would have been surprised with the recoil had I not discovered the error, but that's about it.

 

[ConcernedCitizen]

Even though it's not as economical, I like using a slower-burning powders because they generally fill the case more. One of my absolute favorites for light loads is Trail Boss, which instead of flake or ball powder is a bunch of fluffy little donuts!

 

[PNWguy]

Even though it's not as economical, I like using a slower-burning powders because they generally fill the case more. One of my absolute favorites for light loads is Trail Boss, which instead of flake or ball powder is a bunch of fluffy little donuts!

My favorite plinking load for my .45 Colts is 6 grains of Trail Boss behind a 250gr cast bullet.

 

[xtratoy]

I have read through this and while I see mention of progressive press's I didn't see that you mentioned whether you used a progressive or single stage press. Do you use a taper crimp or roll?

 

[JCKelly]

Glad you are OK.
No doubt you did everything right.
As for myself, I am the sort of guy who measures once and cuts three times.

Yes, I know that is stupid but it is just the way I am.

One day my Ruger .357 was shooting amazingly flat at 100yds in a handgun silhouette match. Nothing broke but I did become aware that REALLY STUPID would be for a guy like me to continue reloading. Ammoman & Midwayusa have good ammunition, and it is priced cheaper than glass eyes or plastic fingers.

 

[MrRob96]

I advised him that was not a good idea but he had been in the Marines so what did I know about shooting?

Too bad you weren't there to advise him on his worst decision of all, to join the Marines.

For sure, former Marines should NEVER be trusted to reload.

*Puts on a dixie cup and sails away*

 

[crstrode]

A man's gotta know his limitations . . .

 

[tac]

Glad you are safe. I have had 1 major kaboom like yours, and it was with someones' reloads.

I don't shoot ANYBODY else's reloads.

 

[Boboclown]

I'd advise against shooting another man's load. Unless you're into that sort of thing.

 

[tac]

Re Post #38 - The text reads - 'it is unclear if this is a factory original barrel or an aftermarket one'. Well, IF they'd shown the other side it would have been clear in a split second, as the REAL Glock barrel would have Austrian proof marks stamped on it.

 

[JCKelly]

Light loads of fast powder, or so I hear, occasionally give very high local pressures which wrecks the gun. Normal reaction is to blame (incorrectly) this on a double load. It is most common in centerfire rifles when one uses very light charges (of the powder normally used for heavy loads). There used to be a "lovely" example of such a thoroughly disassembled rifle in the Flint & Frizzen Shop, Clarkston, Michigan.

I am told the same may happen with handguns, e.e. the .38Spl for which a light load is 2.5 grains of that very fast 40% nitroglycerine powder. Gun comes apart, of course the guy double loaded with this powerful stuff.. Never mind that an intentional double load is quite unlikely to blow the gun, at least in one shot. I am told - no verifiable personal information - that the powder makers would rather you not think about these things.

Guys who may actually understand this sort of things tend to be in the US Army artillery.

And to the guy who mentioned this, yes I am aware of my limitations w.r.t. handhoading. Hence I buy factory produced ammo, & give away the empty cases. Enormous ammunition factories do make the occasional error, but a lot fewer than I, at least, do in my basement.

 

[JCKelly]

I noticed that, bad as the revolver failures looked, they were not in such a location to remove fingers or otherwise mangle hands.

Jest sayin'

 

[ConcernedCitizen]

I noticed that, bad as the revolver failures looked, they were not in such a location to remove fingers or otherwise mangle hands.

Jest sayin'

The cylinder gap on the big boys (.460, .500 S&W) has been known to take fingers, though.

With a revolver, my worry would be the top strap, and where it's off to in such a hurry...

 

[Member 34319]

Found something today.

 

[P7M13]

Just last week, I was at SafeFire when much the same thing happened to my M&P Shield 9mm while firing some commercial reloads.
As the echoes of my "OS!" died away, I took a shaky inventory.

Glad you are OK after yours. Mine was more a "WTF was that?" I saw the dirt fly beyond the target, but it felt wrong. Looked at the gun, and it was an un-extractable case (had to hammer). I've never had body parts blown off, but I've been impaled, had really bad gashes, and had skin ripped off fingers by shavings and parts from machine tools. That feeling is unmistakable.
Both hands, where they were near the slide, were totally black.

I have read through this and while I see mention of progressive press's I didn't see that you mentioned whether you used a progressive or single stage press. Do you use a taper crimp or roll?

Progressive (Hornady LnL), Lee Carbide Dies with Taper Crimp, and also have an RCBS set with a roll crimp for lead bullets. I first set up doing taper, noted I wasn't getting enough grab, tried roll crimp, and while I liked it more, the lack of cannelure or groove on the Montana Gold bullet made it so the roll put a semi-rib in the assembly. Readjusted the taper crimp and was satisfied.
My estimate of 10# force is just that. When I pick up 10#, it's very light to me, so I was probably testing with more.

 

[JCKelly]

Anyone can err, but normally I keep fingers away from the cylinder-barrel gap on any revolver.
I like how revolvers seem more able to digest improper loads while rarely crippling the shooter.
Such "muscle memory" as I have favors revolvers anyway. And at 8 yrs beyond Moses' expiration date I'd rather not try to re-teach them there muscles. I'll just live with 5 - 7 shots, maybe on a really bad day fired directly from my pocket.

 

[zenbreath]

Another possibility....glock bulge.

This happens when a case isn't fully supported by the chamber. First use of factory brass will be perfectly safe, but will have a small bulge where the wall meets the case head. Most sizing dies will not fix this because it is where the shell holder meets the die. Second, third or fourth loading can cause the case to rupture in the chamber.

Lyman makes a push through die that straightens the case top to base.

Its one more time through the press but I do it with all my .40 brass.