Muzzle Loader Question - Blackhorn powder

[Dorkus]

I do not know if this is the right area in OKS to post this question, but will roll the dice thinking it might be.

Here is the deal, earlier this year I started using blackthorn from all the good reviews. I like it quite a bit and it seems to shoot straight and is very easy to clean up for a ML. What is odd about it, the powder expands after I put it in the measuring vials. I have noticed this in the past but did a little test today to see if I am crazy.

My wife thinks that I am crazy but anyway, here is what happened. Around 2:00 today during a boring conference call, I filled six sealed vials with exactly 90 grains of powder. I just went and checked the vials and now they have approximately 98 grains of powder in the tubes. They obviously are expanding while out of the Blackthorn container which I don't know why because the containers are sealed that the charges are in now. Anyone else ever notice this or do I just have a bad batch?

My next question is, what do I use for my charge? I originally measured it to 90 grains and do I use that now even though it is at 98 grains or do I dump some back in the bottle?

Thoughts?

 

[BearSitsInTheWoods]

Following this. Used blackhorn for years now never had an issue, year old charges still go bang.

 

[Dorkus]

Here is an example and when I filled it, it was definitely on 90 grains:

 

[AER244]

I’ve had similar results. I didn’t measure the expansion like you were able to, but every extra shot I’ve ever measured after the season has not gone back into the 90gr by volume measurer that I poured it from originally. It’s all gone bang and hit where it was supposed to every time though. I personally wouldn’t worry over too much, but it is interesting. Soaking up humidity maybe?

 

[Dorkus]

I’ve had similar results. I didn’t measure the expansion like you were able to, but every extra shot I’ve ever measured after the season has not gone back into the 90gr by volume measurer that I poured it from originally. It’s all gone bang and hit where it was supposed to every time though. I personally wouldn’t worry over too much, but it is interesting. Soaking up humidity maybe?

Would you dump some out for this weekend or just load as is?

 

[Oklahomabassin]

Is the pic rotated? Otherwise its defies gravity as well.

 

[turkeyrun]

I like Blackthorn.
Never noticed any expansion. Not that it isn't there. I pour my charge and put it in possibles bag until use.

I would use it and not over think it.

 

[AER244]

Would you dump some out for this weekend or just load as is?

I’d personally just roll with it how it is. I doubt it makes much difference within normal muzzleloader distance.