Varget gets slower

[243BR]

Has anyone had the experience of Varget (or any powder) getting slower as you work thru a jug? Maybe it's just me, but it's happened twice. This last time I was a full grain higher on the old jug. That is to say that when I switched I had to come come down a full grain to maintain the fps that I wanted. Basic load 6br, 108 bbtt, 30.0 varget.

 

[Dgd6mm]

No, but I have had the barrel get slower as the round count down the tube gets higher.

 

[Mikemontminy]

No, but I have had the barrel get slower as the round count down the tube gets higher.

Moisture may contaminate powder after the seal has been broken on the powder container. This will add weight to your powder charge so less powder and more moisture equals lower velocity. If you throw charge by volume instead of weight I don’t think it would show much difference in velocity as you work through the container.

 

[Liven The Dream]

Not in my case.
I find a difference in Lots of Varget some slower and one much faster a few years back.
I try to buy same Lot # when possible.

 

[lpreddick]

Has anyone had the experience of Varget (or any powder) getting slower as you work thru a jug? Maybe it's just me, but it's happened twice. This last time I was a full grain higher on the old jug. That is to say that when I switched I had to come come down a full grain to maintain the fps that I wanted. Basic load 6br, 108 bbtt, 30.0 varget.

I once commented on this and was told I was full of it. Open a new container of Varget and inhale...ETHER! Ether is used in making Varget and ether is explosive! I opined that loaded rounds with a new container might have enough ether to add to the pressure curve. .2 gr of powder can make or break an accurate load. Hodgdon surely has data on this concern. When I open a new container of varget, I pour into a large plastic bowl and "air it out" until the strong ether aroma is minimal.

 

[GrocMax]

One of the speed tuning variables for a powder mfg is how much of the main solvents are left in. Dry it out and remove the solvent = faster. Let it absorb water from the air = slower. Extruded powders are more hygroscopic than multicoated ball powders.

 

[K22]

No haven't experienced this and I've using Varget in various calibers (i.e. 223, 243, and 308) for over 10 years.

 

[MagnumManiac]

Yes, lot to lot changes do exist. ADI strive to keep lots within 3% of each other, but as nitrocellulose is quirky in how much moisture it gathers during manufacture, it is virtually impossible to get the exact same lot as the previous one.
I worked at the ADI plant here in Australia that makes Hodgdon powder, ALL of it is softened with Ether and other solvents to facillitate extrusion, then it is cut and air tumbled to remove 99% or thereabouts of ALL the solvents used. Ether has a very strong smell, even tiny amounts, and when packaged, this is the overpowering smell when you first open a bottle/keg of it.
Ether does not change the burning characteristics of the powder, moisture content and exposure to UV certainly does.
All powders lose some energy over time stored, I had 30yr old IMR4320 that was 200fps slower than a new can.

Cheers.

 

[Dusty Stevens]

Powder adsorbs moisture so the charge gets heavier which in turn you use less powder if youre weighing therefore less velocity

 

[ClassCat]

No powders are created equally. They vary from lot to lot. Thats just a fact. Dusty is correct. Humidity affects volume and weight.

 

[Clancy]

You can load 1400 or so 6.5x47 Lapua cases (example) with a “jug” of Varget.

That many rounds is going to require a few tweaks to seating depth and powder charge.

I’d bet a fistful of dollars that’s what you’re seeing.

However, your post referenced a new jug, but also asks about “as you work through a jug” so I’m a little confused.

 

[MagnumManiac]

As you work through, I’m guessing here, an 8lb jug, it’s moisture content is going to increase as it is opened and poured into smaller jugs to facillitate pouring into a measure or whatever you use. This is mostly a traite of single base powders, double base powders, including those of the stick variety are virtually water proof due to certain chemicals used as flame deterrants that are hydrophobic in structure.

Powder enclosed in loaded ammo should not change over time as air cannot easily pentrate, although powder exposed to radical changes in heat over time will degrade faster. I like my ammo to feel cold when I get it out, this is why my ammo is stored in sealed ammo boxes.

Cheers.

 

[243BR]

You can load 1400 or so 6.5x47 Lapua cases (example) with a “jug” of Varget.

That many rounds is going to require a few tweaks to seating depth and powder charge.

I’d bet a fistful of dollars that’s what you’re seeing.

However, your post referenced a new jug, but also asks about “as you work through a jug” so I’m a little confused.

Sorry for the confusion. As I "work thru a jug" I try to keep mv the same. It does take some adjustments as I go. It's happened 2X now that when I get close to the end of 8# and switch to a "new" 8# the "new" 8# requires less powder to get the same mv.
Having read the comments I think it may be the moisture / humidity on the "old" 8# making it slower and maybe the residual ether making the "new" 8# faster.

 

[tkill]

Moisture may contaminate powder after the seal has been broken on the powder container. This will add weight to your powder charge so less powder and more moisture equals lower velocity. If you throw charge by volume instead of weight I don’t think it would show much difference in velocity as you work through the container.

I've heard this stated a lot, and always wondered something... If water absorption by the powder kernels increases each kernel's weight, wouldn't that same water absorption increase that kernel's size (volume) as well?

 

[rwj]

I've heard this stated a lot, and always wondered something... If water absorption by the powder kernels increases each kernel's weight, wouldn't that same water absorption increase that kernel's size (volume) as well?

If water is present, it will flash to steam upon ignition...

 

[6MMsteve]

I once commented on this and was told I was full of it. Open a new container of Varget and inhale...ETHER! Ether is used in making Varget and ether is explosive! I opined that loaded rounds with a new container might have enough ether to add to the pressure curve. .2 gr of powder can make or break an accurate load. Hodgdon surely has data on this concern. When I open a new container of varget, I pour into a large plastic bowl and "air it out" until the strong ether aroma is minimal.

yep we use to kinda cure it open it up and spread it out a day or so

 

[JMayo]

I rotate the 8# jug all around before I pour it in the measure. Enough to do 150-200
Is this a bad thing to do ?
I don't want the end of the jug to be only crumbs.

 

[Dusty Stevens]

I've heard this stated a lot, and always wondered something... If water absorption by the powder kernels increases each kernel's weight, wouldn't that same water absorption increase that kernel's size (volume) as well?

Powder does not absorb water, it adsorbs it. Therefore the volume (size) doesnt increase but the weight does.

 

[dcali]

My guess, and it's just that, is that it's the barrel. Lots of folks report that Varget can have relatively large lot to lot variations. I have not experienced this (mine has thus far been very consistent), but it's food for thought.

 

[Dusty Stevens]

My guess, and it's just that, is that it's the barrel. Lots of folks report that Varget can have relatively large lot to lot variations. I have not experienced this (mine has thus far been very consistent), but it's food for thought.

That doesnt explain his powder getting slower as he works thru the jug