Unique question

[Longone]

So I have this old 4 lb. metal can of Unique that was sealed since the 60’s probably. I just uncorked it to see how it had faired, it does not smell acidic in fact it really has no odor or smell at all. It is a little brownish but I wonder how much of that is from the inside of the can walls which are rusty.
I put some in the powder measure and threw a few, weighed four drops separately compared to fresh Unique. The vintage stuff weighs about 1.6 grains more than current production Unique, I have read in the past that the formulation of Unique had changed but I have no way of knowing if this would account for the difference in weight or not. Next thing I did was to take the older Unique and the newer stuff and drop one of each and burn them side by side, they appear to burn about the same. I realize that this is far from any scientific controlled test but they did light easily and produce the same color orange flame.
So finally my question. Do anyone have any experience with Unique when it went thru it’s formula change way back when? And do you think the difference in weight of the charges thrown would account for the different formulas? And finally, do you think this is worth trying or should I fertilize the lawn with it ?

Thanks for your time, Longone

 

[RicinYakima]

The change came when Alliant used up all the premade Unique that had been manufactured by Hercules. That was about 15 years ago I believe, but don't know for sure. Weight per volume depends upon how much original solvents have evaporated and how much moisture from the air has been absorbed. Since we don't know what your total weight was, we don't know is 1.6 is a big number or a small number in comparison.

If it were I, consider loading a minimum book load in a 38 special case and shooting it in a 357 revolver over a chrony for comparison. Since I live in the desert, we don't have rusty cans. But I don't think I would want rust going down the barrel of my firearms.

 

[Longone]

Charge with current Unique is 7 grains and old Unique is 8.6. I should also mention the cartridge is 45 Colt.

 

[Longone]

Hopefully this comes thru with decent clarity.

 

[KeithB]

The powder in your picture looks OK to me. If it was sealed up and doesn't smell bad I'd probably follow Rick's very sensible advice. A GP100 would be a good test gun for the purpose.

 

[fiver]

their last change was to add about 2% nitro glycerin.
I have a feeling red-dot also got a base ingredient change recently.
I seen quite a change not too long ago in a few powders.
2400 got denser as did Red and Green-dot.
I had to make bushing changes for the latter 2 and the 2400 got darker and was denser also.
the same weight shot the same as the old stuff so it's no big deal to me, but had I not weighed the new stuff before hand I would be shooting some pretty stout 3-1/4 dram target loads.
that is how I would approach this.
weigh out the same amount of both and put them over a chrono, you'll quickly know if one is burning faster than the other.

 

[USSR]

The powder in your picture looks OK to me.

+1. I'd shoot it in a heart beat.

Don

 

[Ian]

I went through this with a few rusty cans of IMR 4198. It shot fine but I wanted to get rid of the little bit of fine red rust dust in there. Putting the powder in a big piece of worn-out 100% cotton tee shirt and shuffling it back and forth shoe-shine style soaked up most of the dust. What you showed there in the photo doesn't have any rust in it that I can see and I'd have no problem using it up. Ric gives excellent advice as usual for going about that.

 

[pokute]

You're reporting a -18.6% change in density between the old powder in the Unique can and current Unique. They are definitely not the same powder. It may be safe, or it may not. The difference in density is too large to be due to moisture absorption or partial oxidation of the old powder. It's also too large to be accounted for by a 2% change in the NG content.

 

[Longone]

This is the can it came from. It still had the metal seal on it till Saturday.

 

[Richinsd]

When ever I am faced with these kinds of situations, and I have been, I have a general question that I ask myself. It is, "what do I have to gain and what do I have to lose?" And base my decision on the answer. At this stage in life, I don't take any unnecessary chances any more.

 

[pokute]

Whatever it looks like, a roughly 20% difference in density indicates that they are not similar in composition and/or conformation.

Unfortunately, the forensic powder database does not provide bulk density data. They only provide flake diameter data.

 

[RicinYakima]

I believe the grey cans are Hercules made powder for commercial reloading companies. Therefore, they do not "even out" burning rates, it is up to the end user to determine how much to use. I have read that it takes about 6 weeks to make this type of powder, so if anything doesn't go exactly right, the burn rate, density, etc. varies. Anything they can't blend into home reloader powder, went to the commercial market. It was good powder, just not useable with published data.

 

[pokute]

Just for the record, what you smell when you smell powder and it has that "chemical" smell, is usually camphor.

 

[Longone]

In the past I remember seeing Red painted cans with labels glued to the sides noting the contents, but this thing has been sitting under my bench for many years and it was time to break it out.
If this was for a commercial loader that may be the reason it just says “Unique” and nothing about the manufacturer.

 

[KHornet]

I would try it but carefully, with at most
recommended starting loads.

Paul

 

[pokute]

Keep in mind that Red Dot without the red dots looks EXACTLY like Unique. Maybe a little less shiny. That's why it has the red dots.

 

[KeithB]

Keep in mind that Red Dot without the red dots looks EXACTLY like Unique. Maybe a little less shiny. That's why it has the red dots.

A good warning if it were an open can, but the OP indicates that it was in a clearly labeled sealed metal can. In general I am leery of using old powder and I believe I have said so here. But if the powder doesn't appear to be deteriorated visually or by smell and it is in a sealed metal container so I can be reasonably sure it is not adulterated then I think it is worth the risk.

 

[fiver]

and at that time we hand loaded.
every new batch of powder was a new batch of powder, we had to start our data all over again.

 

[pokute]

A good warning if it were an open can, but the OP indicates that it was in a clearly labeled sealed metal can. In general I am leery of using old powder and I believe I have said so here. But if the powder doesn't appear to be deteriorated visually or by smell and it is in a sealed metal container so I can be reasonably sure it is not adulterated then I think it is worth the risk.

I meant that in combination with the bulk density being totally wrong, the appearance was no indication of the type of powder. The bulk density in this case is so wrong that it's unlikely to be a batch variation. It's too dense.