Powder weight or volume?

[old_heli_logger]

What matters most? It depends? Calm down...

 

[marchboom]

All I know is that benchrest shooters load by volume. However, I have never seen any tests proving one way is superior.

 

[old_heli_logger]

Thanks! It makes sense... volume wouldn't change with humidity, but weight would

 

[marchboom]

Now is the time to research powder measures to see what the pros are using. Spend whatever it takes to get the best measure. You won't regret the money outlay and you will love using a quality measure.

 

[Doom]

Thanks! It makes sense... volume wouldn't change with humidity, but weight would

Not true. Volume does change with humidity. Last check water occupies space.

All I know is that benchrest shooters load by volume. However, I have never seen any tests proving one way is superior.

SRBR shooters don't worry about minor velocity variations as they have very little effect on their POI. I'll let the Longer shooters comment on that discipline.

As to which is more important? Weight and volume are tied together through the powder bulk density. The way that the powder combusts is related to case fill and powder orientation. So consistent case fill tends to drive combustion consistency. Within reason depending on the powder and case fill the method that gives the most consistent case fill might be shown to be superior.

 

[Straightshooter1]

this ^^^^^, what Doom said.

Powder kernels expand or contract as they loose or absorb moisture.

And I'll add, while consistent case fill is very important, another aspect of that as well is having the case at or close to 100% case fill. When the case if filled at 100% or so, ignition tends to be very consistent. That's why I always try to select powder that can do that for me.

 

[Webster]

Thanks! It makes sense... volume wouldn't change with humidity, but weight would

Volume of a powder isn't the same as volume of a liquid. What do you think drop tubes are for? If you shake it or drop it over increased height it compacts more. Someone said bench shooters measure by volume, I don't think that's true. Why is everyone buying $1000 electronic scales?

 

[marchboom]

Would be interesting to take a survey of pro benchrest shooters to see what measuring devices they are using.

 

[Bronsin]

It's a rarity to see someone using a thrower anymore.

 

[Rat Rifle]

Why would precise weighing not also equal precise volume ?

 

[Emmett Dibble]

Why would precise weighing not also equal precise volume ?

The only way precise weight wouldn’t equal precise volume is if there was a large variation in kernel size/weight…. I’n no expert but believe that a variation large enough to vary weight=volume would also vary volume to volume thrown equally….

 

[357Mag]

What matters most? It depends? Calm down...

Old heli logger -

Howdy !

Another factor in the “ mix “ is cartridge “ load density “.

It is even possible in mumerous instances and with the use of a suitable powder,
to arrive at the best obtainable accuracy along with safe pressure…. concurrent with the case being completely filled w/ powder.

For example:
When range testing my “ DEEP 6 “ wildcat, best accuracy was obtained ( when shooting Sierra 85 BTHPs ) with the case was completely full of IMR7828.
And both pressure and velocity were fine. These loads utilized FED Large Magnum Rifle
Match primers.

Shooting Hornady 87 “ V “- Max in the same wildcat case and in the same rifle,
best accuracy was realized when shooting the case completely filled with RL-25.
Again, the loads utilized FED GM215M primers; with both load pressure and obtained
velocity being just fine.

Seating the 87 “ V”-Max .002” off the lands ( my wildcat rifle, my loads ) results in the bullet’s boat tail being located slightly into the RL-25 powder columne; with just a hint of compression.


With regards,
357Mag

 

[jelenko]

I've found GRT [inputing dimensions of case capacity, bullet weight and length, COAL] to be helpful in finding powders that would fill the case, have a high burned % and still be below max pressure.
If I don't have the bullets on hand, I use the lengths from JBM Ballistics. The actual length will have far less effect than when I enter the observed velocity from 8-10 shots.