Open Powder Lifespan

[2428 miles]

Evening all,

Any guidance on the lifespan of an open bottle of powder?

I recently had some very erratic Chrono results from a batch of Vhit N150 that I first opened in 2011... I'm wondering if the powder is past it's best or the problem lies elsewhere.

Thanks in advance,
Miles

 

[finnbear270]

How has it been stored,? In a dark cupboard, in full sunlight, cool, hot, ??? Etc etc.

 

[8x57]

It's unlikely that the actual age of the powder has any relevance its more to do with how the powder has been stored. I've used powder that was at least 30 years old and not had any problems with it but then it has been stored in a cool dry place since first purchased. Moisture and extremes of temperature are the killers.
When you say that you have very erratic chronograph results I wonder if you have been shooting outside in the sunshine on a hot day. The latest Vhitavuori powders are said to be far more temperature tolerant than the powders that they replace.

 

[finnbear270]

How is the powders fragrance?

 

[2428 miles]

It's been stored in a cool dry cabinet.

Smells normal... if a little stronger perhaps

I understand that un-opened bottles/canisters can last for decades but this has been open for 9 years... so not insignificant.

The Chrono was jumping from c. 1,300fps to c.2,800fps in a string of shots... POI hardly changed a jot though. This is .30-06 with a 150sst 52.5 grain of N150. The latter number was the fps I was expecting. I have heard of variance but this was a whole new level!

I'm going to do a side by side comparison with a new un opened bottle this week but wondered what peoples thoughts were.

Initially I thought the problem was having the chrono too close the the end of the barrel.... but I shot another group from another rifle, same position and then readings came up fine, consistent and accurate. So I'm a bit stumped hence thinking about use by dates once opened!

Thanks all,
Miles

 

[MAH]

The Chrono was jumping from c. 1,300fps to c.2,800fps in a string of shots... POI hardly changed a jot though

That's seams odd. The laws of physics say that given the variation in velocity , the poi should change. Are you sure the chrono is ok?

 

[Alantoo]

Those symptoms...that range of velocity with no change of POI I would definitely suspect the Chrono first.

What range to the target?

Alan

 

[Muir]

I've got some powder from The Korean War. Still good.~Muir

 

[Stalker62]

I've got some powder from The Korean War. Still good.~Muir

Jesus Muir,
If SD was a game of "Top Trumps" - you would win every time...

 

[Muir]

Well.... it was an example to answer the question.
And as it so happens, I was giving reloading lessons this week and the person asked how long powder was good for. I said I had a tin of powder that was surplus (pull down) from the late 50's and we dumped it out to see if it was spoiled. Acetone smell was still there though faint, no discoloration. I'm assuming it was still good though I believe I won't use it any more -just keep it around for lessons. Eventually it will start to shed it's coatings and turn orange.

Now, ask me how many Vhit powders I load...... ~Muir

 

[2428 miles]

Thanks all!

Range was 100y.

The Chrono is a Caldwell. No issues with it until now... as far as I'm aware.

One error I definitely made was not having the Chrono in excess of 5ft from the barrel...

Thanks,
Miles

 

[jb1]

I would double check powder charges, if you can check POI at 200yds. If POI is the same it wont be the powder.
The weak link is usually the human one in these types of scenarios.
We rarely doubt ourselves, when in fact we should check our data input 1st off.

 

[Alantoo]

The optical chrono I used had to be a minimum of 10 feet/ 3 metres in front of the muzzle for centre fire. It could only be as close as 5 foot for rimfire and shotgun.

I had a series of weird high readings...one session consistently 400fps too high, and lots of errors when using that in lower light towards sunset...so much so that I got fed up with it and bought a Magnetospeed.

An inaccurate/unreliable measuring device is worse than none.

Alan

 

[Andy RV]

Dodgy chronograph!!

 

[2428 miles]

Hi All,

Thanks everyone for you thoughts and suggestions.

The problem was indeed that I had the Chrono too close to the end of the mod, so the muzzle blast was interfering with the reading. I can't believe my stupidity, but you live and learn! No harm done and a simple fix!

Thanks again for everyone's input.
Best Wishes,
Miles