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View Full Version : The perferct load


zcar75
November 15, 2010, 04:39 PM
So, I bought a 20 grain flask spout made by Treso. Well, I refernced it with my powder measuring tool and it came out 25 grains. Is this normal? How can one get the right amount of grains for the load?

Fingers McGee
November 15, 2010, 05:03 PM
Spouts are only a nominal representation of the volume that a given weight of powder has. Ideally, a 25 grain spout would throw a charge of powder that weighs 25 grains; but that isn't always the case (probably is rarely the case). Granulation, formulation, and quality of ingredients all factor into the weight of powder.

If you want an exact 25 grain load of powder, you would need to weigh out 25 grains, then cut your spout to hold that much. Of course, your next can of powder may not equal 25 grains by weight using that same spout.

FM

ClemBert
November 15, 2010, 06:48 PM
I've not found nor heard of a single BP volumetric measure that was dead-on. In fact, from what I can tell, every instance points to the measure always throwing less than the advertised amount. I wouldn't doubt if ALL manufacturers are smart enough to make sure their measure throws less than marked as a CYA maneuver.

I bet your powder measuring tool (probably also volumetric) shows that 25 grain load to be less than 25 grains by weight.

Doc Hoy
November 15, 2010, 07:51 PM
...is that you can't see inside to check that the powder in the spout is properly tamped....has no voids.

IMHO, a very important aspect of measuring powder is consistency of the powder charge. Is it important to know what the charge is? Of course it is, but it is no good if your 25 grain spout sometimes throws 25 grains and other times throws 15 because the powder failed to properly fill the spout.

You generally don't find out about this until the charge goes into the chamber and you can see that one chamber is not as full as the next.

This is a good reason for scoop measures or other types that allow you to see the powder going into the measure.

ClemBert
November 15, 2010, 08:38 PM
Doc, I'm one of those fellas who uses the "see-thru" type of measure. I use the Thompson Center U-View measure (http://www.midwayusa.com/viewproduct/?productnumber=714741). It has a "wiper" to ensure consistency. And the spout is funnel shaped to make it easy to pour the powder in the chamber without spillage.

http://media.midwayusa.com/ProductImages/Medium/714741.jpg

Doc Hoy
November 15, 2010, 09:11 PM
Yes...good consistency and easy to use.

sltm1
November 15, 2010, 09:27 PM
The difference between volume weight and scale weight is pretty small, weigh out 25g and see what that equals in the spout. As others have mentioned....no guarantee that the next can of powder will be exactly the same granulation consistancy.

mykeal
November 15, 2010, 11:50 PM
The difference between volume weight and scale weight is pretty small
...assuming that the volume measure is accurate, of course. Which, in my experience, they aren't. I have 4; they vary as much as 13% from weighed charges.

sltm1
November 16, 2010, 09:15 AM
mykeal, what I was implying is that the scale weight is what you should use to figure out what the volume weight actually is....then you could adjust your funnel to match.

Noz
November 16, 2010, 09:46 AM
I chased the weight/volume bug for a couple of years before I realized that unless you are shooting long range precision rifles, a few grains of black powder one way or the other makes no discerable difference.

Not worth the effort to fight it.