Problem?

[Qtiphky]

Just got done reloading for the 10 and 45 using a new 1 pound canister of Unique as I finally finished off my 4 pounder. I noticed that the new Unique is significantly lighter than the old formula and was wondering if this will cause a problem. For example. I am using the charging die of .76 and with the old Unique it would throw a 6.4 grain charge consistently. With the new Unique it is more like 5.9~6.0 grains. Still consistently, but less and well within acceptable levels so I'm not worried about shooting these, but I do have a question.

The volume that is being thrown should be the same, but the weight is less. Will these new rounds function the same as the old ones that were 6.4 grains or will they have different characteristics. Obviously I will need to use a bigger die to get to the 6.4 charge, but will that then push it into a compressed charge or possibly spilling over the case? Any input would be welcome.

 

[serf 'rett]

Any idea on the age of the previous Unique? Seems I remember Alliant came out with the "new and improved" Unique about 3 or 4 years ago. My opinion, reduce charge and retest while working up. I certainly would not jump the new powder charge weight upward without testing.

Perhaps, if you will tell us specific load information, someone with Quickload will come along and run a check for you.

 

[Valornor]

I might email Alliant and ask them. Do you have the lot numbers of powder? They should be able to tell you if you might get yourself in trouble. Personally I think your probably going to be ok if you were running starting loads...

 

[Nick_C_S]

Alliant did reformulate Unique some time back. Not sure when it was - I was strictly a Winchester powder user for many years and missed when that took place.

I think you have a batch of the two different formulas.

Personally I think your probably going to be ok if you were running starting loads.

^^ Agree ^^

But with your new powder, make sure you're using correspondingly new load data. And weight is always the be all to end all - not volume. Trust your scale.

You have only new powder now. At this point, I wouldn't over-think it. Just move forward - by weight

 

[Jim243]

You have only new powder now. At this point, I wouldn't over-think it. Just move forward - by weight

This would be true if the "Burn Rate" is the same for both powders. If not the same then going by volume MIGHT (not always) be the best way to go.

I know when 2400 was changed over from rifle powder (metal can) to pistol powder (plastic bottle), the same "weight" of rifle powder (metal can) would definitely damage any revolver or at least stress it quite a bit.

Jim

 

[Murphster]

And I thought I was the only one. Thanks for posting. I've noticed the same thing lately. Started to doubt my load notes from years ago. But I agree. New Unique seems to weigh less when thrown by volume (I use a Little Dandy). Nothing to be done but reweigh and reassess which rotor to use. Still a great powder.

 

[WESHOOT2]

learnt vs burnt

I learned (defined as "a change in behavior") to start anew when changing the lot of any component.
Like powder.

'New' Unique, IMNSHO, is different enough to demand a full work-up.

 

[TimSr]

I've still got a bunch of the old stuff. The new formula is supposed to be cleaner and less smokey. The old stuff was pretty nasty.
For this reason I've done a lot of comparision with old and new data, and find little difference for Unique. Charges should always be based on weight. I really doubt you'll ever see a new version of a powder becoming dangerous when used with older data just for the likelyhood of bad things happening but I agree with those who suggest starting a new workup as though its a new powder, because it is.

The only powders meant to be charged by volume are those meant to be measured with blackpowder measures in blackpowder arms.

 

[Qtiphky]

I guess I will find out this weekend when I start shooting them. The load listed on the die sheet was starting and ending at 6.0, from Lee. However, in my Sierra book I can run it all the way up to around 6.9 grains if I remember right and well down into the 5 range on the load side, so I'm near the middle with this weight. I have used these loads for years so I don't recall how old my old Unique was, probably 3-4 years old. There is still quite a bit of room in the case, but if they shoot fine I don't think I'll run them any hotter than what is necessary.

Thanks for the input.

 

[LarryFlew]

I see no difference from the 4 year old Unique I have to the new one just purchased other than container. Can't say about older because I didn't use it b4 then.

 

[Qtiphky]

Worked fine and didn't seem to have more or less noticeable recoil. Didn't have time to set up the chrono to check velocity compared to old loads, so I'll do that this weekend.