Oh no, it went tink instead of bang

[texassako]

Yep, it sounded like saying the word tink. Waited a bit then ejected the cartridge and some powder came with it. I looked inside the case and powder has fused into a lump that a screwdriver can break apart with some effort. It was loaded with a j-word to fireform to improved, and luckily there was only enough power to just get it started in the bore. Brand new RP .30-40 brass, 1 yo CCI primers stored inside, H4895 powder only a few months old and only open a month, and just loaded them a few weeks ago. I only had 10 more to fireform out of 100 before switching over to boolits. It sure had me scratching my head for a bit, but I guess it is my first bad primer out of several cases. I just never heard of one with enough flame to toast but not ignite the powder.

[williamwaco]

That happens.
I have seen it with pistol but never rifle ammo.

It is VERY rare and I have no idea what causes it.
There are several theories but I don't find any of them convincing.

[Mooseman]

I only had that happen with 296 Ball powder...a Magnum primer would not set it off, but pushed the bullet 3 inches into the barrel.
It was a brand new can of powder , but a bad Batch !

[Plinkster]

Just saw a guy at the bowling pin shoot last week had the same problem with 4227 in a 454. BANG! BANG! BANG! tink. Had a weird looking clump of powder in it too. Also not sure of the cause but it does happen, just hope it doesn't happen with a game animal or a thug in the sights.

[44man]

Slow powder and how much can I bet you underloaded to fire form.

[leftiye]

Point barrel skyward before aiming and/or firing.

[SquirrelHollow]

The fused lump actually indicates that the powder ignited, but "fizzled" when the pressure dropped - from both the bullet being pushed into the bore and increasing the chamber volume, and the case losing its chamber seal once the bullet was out of the neck.
Smokeless powders need pressure to perform. Break the seal, or increase chamber volume too quickly, and it all goes south.

Light load, I'm guessing?

[Wayne Smith]

Fireform with light loads of pistol powder and that won't happen. I tend to use Unique. What you had is a slow powder that needs pressure to completely burn and did not have enough pressure.

[rexherring]

You didn't say how much 4895 you're using. A tuft of dacron, ceam of wheat, or grex should hold the powder better, or use a faster powder like was said. I use 10 - 12 grs of Unique and a 170 gr Lee cast to fire form my .30-30 improved cases with no fillers.

[243winxb]

The fused lump actually indicates that the powder ignited, but "fizzled" when the pressure dropped - from both the bullet being pushed into the bore and increasing the chamber volume, and the case losing its chamber seal once the bullet was out of the neck.
Smokeless powders need pressure to perform. Break the seal, or increase chamber volume too quickly, and it all goes south.

Light load, I'm guessing?

This answer gets my vote. :-)

[captain-03]

Had this happen twice in the 500S&W Mag -- CCI Mag Primers and BLC2 ... pushed the boolit about an inch and half out of the cylinder ... big clumb of unburt powder in the cylinder .....

[0verkill]

BLC2 seems bad for that. When reloading 7.7 Arisaka with dipper loads I had that happen. The powder clump looked shiny, so since it was clumpy and wet I must have had a drop of powder get inside the case somehow. The second time it happened (about 40 rounds later) I figured something was wrong. My dipper threw charges about 4gr under the start load and I was using standard, not magnum, CCI primers. The 3 factors, a slow powder, too light a charge and a primer too weak combined to cause it. Anybody that's not seen it in a rifle and wants to - there's your recipe.

[frkelly74]

Use Herco. A century of load developement has taken all the surprises out of the equation.

[HangFireW8]

Use Herco. A century of load developement has taken all the surprises out of the equation.

Yeah, I don't know that they've messed with Herco. Yet. H4895 is Made in Australia now, its not the same stuff as the old days when Hodgdon sold military surplus lots of IMR 4895.

Failure to burn at low pressure and clumping has lots to do with inhibitors and plasticizers. These work great to match performance of older powders with modern manufacturing techniques; however they don't work the same at the extremes.

The old single based colloidal cellulose powders (like IMR 4895) were well loved for many reasons, one of which is predictability and tractability at lower pressures. However for reformulated powders, if loads were never published by the manufacturer for the old powder, you can't depend on the new stuff to work the same for unpublished loads.

HF

[Thumbcocker]

I think it was Capstick who said something like the scariest sound he heard in all his years in the African bush was a "click" instead of a "BANG".

[Sakdog]

Been here many a time too with pistol powders. I think that mine mostly had to deal with using old WW231 and some heavy metal free russian primers. But the same action. It squibbed and left a compressed wad of powder behind the bullet.

The gun that I had the most problems with this was a revolver chambered in 9mm luger. Mine, I think were doing this because subsequent rounds in the adjacent chambers were being pulled out of the case by recoil/lacking a real cannelure...

I never got that combination of auto caliber revolver and lead bullets to work.

[deltaenterprizes]

I had a similar experience with WW296 with LP primers in
10 degree weather, how cold was it where you were shooting?

[texassako]

The fused lump actually indicates that the powder ignited, but "fizzled" when the pressure dropped - from both the bullet being pushed into the bore and increasing the chamber volume, and the case losing its chamber seal once the bullet was out of the neck.
Smokeless powders need pressure to perform. Break the seal, or increase chamber volume too quickly, and it all goes south.

Light load, I'm guessing?

It was a light, but not minimum load. The brass was expanding to the improved chamber; so maybe dropped it back down to a minimum load pressure? I did not crimp either. Oh well, that load was not going to be used again since it was just to make my improved brass.


I had a similar experience with WW296 with LP primers in
10 degree weather, how cold was it where you were shooting?

It seldom gets that cold here, and was about 85deg that day.

[Larry Gibson]

What weight J bullet?

What actual charge of H4895?

Larry Gibson

[Goatwhiskers]

Have to ask, perchance are you shooting the 30/40AI? GW

[texassako]

What weight J bullet?

What actual charge of H4895?

Larry Gibson

125 gr over 40gr H4895. Sorry I missed someone asking that above when I did not notice more responses in the thread.


Have to ask, perchance are you shooting the 30/40AI? GW

Yes, it is a .30-40 AI.