Weird occurrence with a reload

C

chris in va

New member
Fired a few dozen 155gr lead GC through my x39 carbine today without issue. 23gr 4895 IIRC, I'd have to check the exact formula.

One fired with what felt like normal recoil but I didn't see a bullet impact so I pulled the bolt. There appeared to be something in the bottom half of the barrel, partial daylight. It wasn't a bullet but I blew in the chamber and a fair amount of unburned powder came out.

Is 4895 notorious for being hard to ignite?
 
but I didn't see a bullet impact so I pulled the bolt.
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I know this might sound funny, but could you have loaded one case with just the gas check and no bullet?? Or maybe fired a blank by mistake?

Jim
 
Is 4895 notorious for being hard to ignite?
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No, Hodgdon has Youth loads that are reduced. I used IMR 4895 with reduced loads with no problems. If a bullet was to small in diameter, it may not build pressure to burn the powder correctly. An auto loader may have bullets moving forward when it slams into the chamber. Chanber and extract without firing, see if the bullets are moving. Longer OAL.
 
Just a guess but perhaps there was something in the case (water/oil) when you poured the powder in. It's not likely that you found that much bad powder in a one pound can and then managed to group them all into one casing. I am assuming that you used the correct primer and like I said, it's just a guess.
 
Contaminated powder.


H4895 and IMR4895 are great powders for reduced loads - specifically because they're easy to ignite and tolerate low pressure better than most rifle powders.
 
They are, but I'll note that Hodgdon only recommends H4895 for the purpose. I talked to one of their techs one time, and they said that when it was reformulated to be made by ADI as one of their low temperature coefficient Extreme line of powders, they did some specific low load testing of it and found it will perform reliably down to 60% of published load maximums. They make no such claim for the differently formulated IMR product. That may be significant, as IMR changed their manufacturing process recently, claiming the old one had become uneconomical to continue with. So, until the new process IMR 4895 has been wrung out, performance at the extreme ends of the range should probably be given a question mark.

In this case, QuickLOAD thinks, depending on exact case water capacity, you would be operating in the 14-15 kpsi range when the powder burned correctly, and obviously at less when it didn't. That's really too low for something as slow as a typical medium burn rate rifle powder to sustain burning reliably. While powder will burn at air pressure out in the open where air supplements its oxygen, in confinement where there is no open flame, the temperature and pressure have to hit minimums for the powder to keep releasing oxygen fast enough sustain its burn. I've seen IMR 4831 do that, where you just get a bunch of stuck-together grains, often yellowish from the graphite having burned off before it extinguished itself. Usually its with a bullet that doesn't generate enough resistance the powder to build pressure against, either because of what it is made of or what it weighs. In this case, QuickLOAD thinks a jacket on the 155 would raise pressure about 25%, for example.

In any event, it appears from QuickLOAD that Rocky Raab's universal .30 caliber light load of 9 grains of Unique will give you about the same velocity at a more reliable 27,000 psi and cost you about 2.5 times less for powder.
 
"...23gr 4895..." Which one? Both are rarely used with cast bullets. What the exact load data used as matters.
Sounds like the last one was too long, got stuck in the rifling and got pulled out. A 155 is a very big bullet for a 7.62 x 39. So the OAL would be critical.
Just the gas check and no bullet would sort of stand out when the thing was loaded into the mag. And if the powder was bad it would've been more than one.
 
good point o'heir. I have done that a few times, but only when manually extracting. how would that happen before firing?

unless your saying the next round he unloaded to check the barrel left the powder, but then the bullet would be there too
 
I know this might sound funny, but could you have loaded one case with just the gas check and no bullet?? Or maybe fired a blank by mistake?

Jim
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I thought of that but no. It was the last shot of the day and when I go home I tapped the barrel onto one of my white IPSC targets and more unburned grains fell out, so it was definitely powder.

I jst checked my bag, they are 24gr 4895, almost completely stuffed full.

It's the only one to do that so I'll chock it up to a bad primer. All the others fired fine.
 
T. O'Heir said:
Just the gas check and no bullet would sort of stand out when the thing was loaded into the mag. And if the powder was bad it would've been more than one.
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I've had contaminated powder in a single case, before. You can contaminate a single powder charge without ruining an entire canister.

In my experience, it is generally caused by that case being contaminated before being charged, or the base of a bullet being contaminated before seating.

Sucks, but it happens.


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Unclenick, thanks for bringing up the reformulation. I knew it had happened, but I never remember. All of my IMR4895 is from 1998, or older. (Well, most of the H4895, too. :rolleyes:)

When I was experimenting with .22 WMR handloads, I became increasingly familiar with the fused clumps of yellowed unburned powder, with each new experiment. After a while, the sound of the report was enough to tell me whether I had low pressure with a stuck bullet, or low pressure with fused powder and a stuck bullet.

This one (below), however, was special. I was using a heavy weight bullet with a powder that I considered too slow for the application - H4895.
Several rounds fired prior to this one resulted in stuck bullets and fused clumps of yellow powder granules in the barrel. (I work up really slowly with ridiculous things like handloaded .22 WMR, even if I still appear to be well under operating pressure and believe the charge will be heavily compressed before there's any chance of over-pressure).

But, this one....
This one launched the bullet at what I figured to be 1,200+ fps, and the powder never left the case. It fused in place. On top of that, it was jet black, glossy, and resembled something like Titegroup, more than H4895.

It's nothing terribly impressive. But it was an outlier and an oddity. ...Surprised me and caught me off guard.
It doesn't look like it, but that's H4895.

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The case rolled around on my bench for about 8 months, until I decided to give up on the .22 WMR. (There are better ways to waste money.)
When cleaning the bench one day, I decided to keep it as a reminder of WHY I stopped trying to handload for the cartridge. So I just put a drop of white glue on the powder to help stabilize it, should it ever decide to break up. That's what gives it the look of being sealed.
 

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. They make no such claim for the differently formulated IMR product. That may be significant, as IMR changed their manufacturing process recently, claiming the old one had become uneconomical to continue with. So, until the new process IMR 4895 has been wrung out, performance at the extreme ends of the range should probably be given a question mark.
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Unclenick :

When was this changed manufacturing process started . Before 2013 ?
 
I only read mention of it within the last year, it seems to me, but don't know when it actually came about. The best thing would be to call Hodgdon and ask. What is unknown when such a change occurs is how much it may affect the powder's characteristics at the extremes of its operating range. Obviously they'd try to keep it as close as possible to working with existing load data, but once you get outside that charge range it could get different. QuickLOAD's author says the reason he's never included the IMR pistol and SR powders in the database is they have changed sources and processes too much over time for adequate consistency. I'm certainly hoping the change to the IMR rifle line has not been for the worse.

I think what happens with fused powder is the burn that begins back near the base of the powder column doesn't raise pressure fast enough to get ahead of the bullet starting to move forward and expanding the powder burning space. That expansion also lets the hot gas spread forward through remaining unignited powder grains. That expansion to larger volume simultaneously drops the gas temperature, with the result that the phase change of the powder from solid to liquid at the surface uses up a larger share of the available heat in the gas, keeping temperature down below the combustion threshold. In a normal load, the powder burn rate and charge weight have been selected so pressure rises faster and before the bullet moves very much.

The hidden hazard to that fusing is it makes the powder mass contiguous. That, in turn, makes it possible to detonate, as the lack of separate grains leaves it without a way to break up a shock wave. While detonation is extremely rare, I have long theorized that fuzing probably is a required first step, and that scenarios that fuse powder should therefore be steered clear of.
 
I asked because IMR 4895 is one of my most used powders . I've been buying it on and off for the last two years and was hoping I don't have a mixed stock of powder . Last year I bought 4lbs and just added it to the 2lbs I had left in a 8lb jug . I then dropped my next loads by 1.5gr and worked back up . In that case the same 40.7gr pushing 175gr smk still worked well . None of my commonly used loads are at max though and I've never tried reduced loads .

I'll email them so I can cut and paste there answer word for word .

Thanks

This is the email I just sent
Hi , I just read that you changed the manufacturing process for IMR 4895 . If you can would you please tell me what year that was and or at what lot number that change was made ? I'd also like to know if there are any characteristic differences from the old powder compared to the new powder ? Specifically at the low and high ends of pressure . I have generally loaded in the mid charge range for 308 & 223 wylde chambers . I've loaded the same loads regardless of powder lot in the past . I'm concerned if the powder has changed I should work up new loads . Right now I have 12+ lbs of IMR 4895 with at least 3 different lot numbers . Would you ever recommend just mixing them all together real well and start new load development with the mixed powder ?
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That sounds like a rumor from the internet.
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Where else would that information come from? I have had a few rounds that did not feel and or sound normal. Once I removed the bolt and found what looked like pop-corn in the barrel. The powder turned to fluff, no one to blame, I did it. No matter what it was.

The rifle was a 308 Norma Mag I built from M1917s. I took one box of new Norma 308 Norma Mag ammo and two boxes of reloads to test fire. What happened? The Shadow was not there, but I thought the powder was just tool slow and the bullet was not heavy enough.

As suggested, I have ejected rounds when the bullet remained in the throat as T. O'Heir suggested. No trace of smoke in the barrel when the bolt was removed, just unburned powder.

F. Guffey
 
H4895 made by ADI evolved from a very simular powder. Then the color was changed for the US market. Hodgdon has made the exact same powder ( IMR4198) in 2 different countries. Gets very confusing if you try to follow it all.
 
Metal god,

Thanks. I should have made that check myself awhile ago. Can't recall where I read it, but I didn't think it was an Internet post. Getting old, though and may not remember correctly. I do know their SR and #00X powder sources and processes have changed some over time, as that came from Hartmut Broemel as the reason he doesn't have models of those powders in QuickLOAD. He's measured the changes and doesn't trust anything he puts into the program to remain good over time.
 
I thought i read something from Hodgdon, that IMR 4350 was the one that got changed? But i cant find it again. Like Unclenick said, getting older. 70 here. :)
 
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