Ganderite wrote an article about the powder in those called back cases.
Apparently some pistol powder got put into one of the hoppers.
He took all of the powder and just dumped all of it into a large container and mixed it all together, then used it for plinking ammo.
I don't know how much of that stuff you have but the rounds doing the damage were mixed in with others that were loaded with the proper ball propellant.
If you've pulled the bullets before, you'll remember they used a black tar like sealant, that you have to break the bullet/neck free of.
If you clean those bullets, to remove that sealant, then weigh the bullets, you will be pleasantly surprised by how consistent the weights are. Quite good bullets for milspec from South America
The boxes should be labled in Portuguese "REINGESTADA" which roughly translates to reinserted or refilled.
Back when that stuff was first offered, I picked up a lot of it on group orders for some of my shooting buds as well as myself.
We bought maybe 20+K. I had four cases left and sold one to my next door neighbor.
He had just received a lovely 98 match rifle and wanted to shoot it, but didn't want to handload.
Out of all of those thousands of rounds and about half way through his case, he had a kaboom, that ruined the rifle and blew a tiny bit of brass back into his eye.
Yes, he always wears glasses now.
A few years ago this was brought up and Ganderite made some comments.
Shortly after that, I found a case of that batch, which I had set aside. The two other cases were shipped back to International, on their dime, for a full refund and some gift certificates which came close to what paid for the ammo. They never asked us to sign a waiver.
Anyway, I took that case of ammo and pulled all 1000 bullets.
Washed the tar off them in varsol, polished them
I put all of the powder into a 25 liter metal bucket and mixed it all together.
It had a burn rate, very similar to W748, of which I had several part containers, so I mixed that in as well.
The original powder charge in my ammo was around 46.0 grains average, which would be right in the ballpark for a W748 load with 150 grain bullets.
I got around 46k grains of powder from those cartridges and mixed it with another 3+ pounds of mixed lots of W748.
I reloaded all of those cases with the mixed powder lot and bullets, using 45.0 grains
That left me with almost 3.5 pounds of this mixed propellant, which was very consistent in burn rate.
If you've got a bunch of that powder, say enough for 1k rounds, I would happily take it off your hands, if I was close by.
I've shot all of that 1k rounds out of a Danish 98K conversion Match rifle and used the powder for reloading for that same rifle.
It's your powder and if you have enough to load a thousand rounds, IMHO it would be well worth blending it all together and maybe adding some powder of similar type.
You should be able to figure out what's in the cartridges by the weight of the powder and comparing it to loading tables.
All of mine used ball type powder. I suspect it was all loaded with ball type powder.
The Brazilians loved using powders similar to H335/W748/W760.
Of course, if you're uncomfortable doing this, DON'T. Or if there isn't enough to bother.
