Reloading is the process of reconditioning spent casings into ready to fire ammunition.
In this process there are many permutations and processes, today we will look at how to determine how much powder gets in the case and how to keep the amount consistent.
There are several methods to get the proper amount of powder in a case.
Scoop method:
This is as simple as it sounds. A given caliber needs roughly a certain volume of powder. A small plastic cup with a long handle is dipped into the powder. The scoop is leveled with a plastic straight edge and this is poured through a funnel into the case.
For pistol plinking ammo this is an acceptable method, in most cases. The issue here is several fold.
- Powder comes is several configurations: stick, flake and ball. Each of these has VERY different volumetric amounts for a given weight.
- All powders have different burn and gas expansion rates, which cannot be adjusted for with a fixed volumetric measuring device.
- Compaction will not be standard in the cup. This is especially concerning with a flake powder.
Manual powder measure:
This is essentially a variable version of the scoop method. A gravity feed hopper is set above a screw adjustable measuring tube. The screw adjusts in or out to change the volume of the cylinder. By making this adjustment and weighing the resulting charge, a fairly precise load can be made. This adjustability allows the amount of powder to be tailored to the style or more specifically the particular powder.
Many manual powder measures have a choice of screw / tube assemblies. A thinner tube and screw for low volume powders (usually below 25 grains) and a wider tube and screw for higher volume powders (20 grains and above). The finer assembly gives a tighter tolerance (0.1 gr) on smaller (less than 10 gr) volumes. The larger assemblies usually provide a similar (0.1 -0.2 gr) tolerance but not until they are dealing with loads above 15-20 grains.
Manual powder measure plus manual trickle charge:
This is a method of using the manual powder measure to intentionally under throw the desired weight and fine tune using a scale and a device that throws a few bits of powder into the scale pan at a time. This allows the recipe to be very consistently tailored and followed. Some people use a manual balance beam scale for this. I use a Gem Pro 250 digital scale. With this method, accuracy is limited by the precision of your scale and the consistency of the powder grain size.
Automatic powder measure:
This is an electronic version of the manual powder measure where the desired weight is inputted and a charge is thrown accordingly. At various price points these vary in precision from +/- 0.2 grains to +/- 0.05 grains. They are usually significantly faster than a manual measure and can be much more consistent. Many people chasing precision will use them with an intentional under thrown weight and trickle charge the final bit manually.
Automatic powder measure with auto trickle charge:
This is the ultimate in simple and speed. When properly set up and a high-end model is purchased, this provides all the precision of manual trickle charging and weighing with a digital scale. The process is all completed within the tool. The real problem here, most reloaders cannot justify the price tag.
Any of the methods listed above will work to turn powder into noise and a moving projectile. Even the scoop method can be fine tuned with a specific scoop for a specific cartridge and a specific powder. It will not be as accurate as trickle charging with a very accurate scale; but if the cartridge, gun or shooter is not precise, it won’t be noticed.