Good job!
Your Gem Pro 250 is as sensitive as the expensive scales - it can detect differences of 0.02 grains.
The key to getting good data is to:
1) Use rubbing alcohol.
2) Make sure the cases have a spent primer in them
3) Put them on the scale and zero the scale.
4) Corse fill the case with a squeeze bottle.
5) Fine fill the case with a small 1 mL tuberculin syringe.
6) To make sure you get consistent and correct fills. Put the case between you and a small desk lamp.
7) Use a head mounted magnifier to look at the mouth of the case at an angle. You should be able to see a reflection of the light on the surface of the alcohol.
8) Fill the case slowly with the syringe until you get a flat meniscus. You know this happens when the reflection of the light gets bigger and disappears. Think of the meniscus as a mirror. When you are getting there it is a concave mirror. When you over fill it is a convex mirror. You are shooting for a flat mirror.
9) Take the case out carefully so that nothing spills.
10) put it on the scale and record the weight.
11) If you want volume in mL, you will need to adjust for the slightly less dense character of alcohol. But this is really unimportant unless you are interested in using the values in Quickload.
At least for you, you are just trying to show to yourself that the volumes are different between the different types of brass. They are of course different but perhaps you want to proof this to yourself which is OK.
Don't worry about evaporation.
Have you measured the overall length of your cases to make sure they are under SAAMI limit which for 243 Win is 2.045"?
Your Gem Pro 250 is as sensitive as the expensive scales - it can detect differences of 0.02 grains.
The key to getting good data is to:
1) Use rubbing alcohol.
2) Make sure the cases have a spent primer in them
3) Put them on the scale and zero the scale.
4) Corse fill the case with a squeeze bottle.
5) Fine fill the case with a small 1 mL tuberculin syringe.
6) To make sure you get consistent and correct fills. Put the case between you and a small desk lamp.
7) Use a head mounted magnifier to look at the mouth of the case at an angle. You should be able to see a reflection of the light on the surface of the alcohol.
8) Fill the case slowly with the syringe until you get a flat meniscus. You know this happens when the reflection of the light gets bigger and disappears. Think of the meniscus as a mirror. When you are getting there it is a concave mirror. When you over fill it is a convex mirror. You are shooting for a flat mirror.
9) Take the case out carefully so that nothing spills.
10) put it on the scale and record the weight.
11) If you want volume in mL, you will need to adjust for the slightly less dense character of alcohol. But this is really unimportant unless you are interested in using the values in Quickload.
At least for you, you are just trying to show to yourself that the volumes are different between the different types of brass. They are of course different but perhaps you want to proof this to yourself which is OK.
Don't worry about evaporation.
Have you measured the overall length of your cases to make sure they are under SAAMI limit which for 243 Win is 2.045"?
