Powder measure question

[Rickk]

I have been trying to make up a set up powder measures to measure Cannon Grade powder in the 150-200 grain range. What I seem to be finding is that Cannon Grade is hard to measure by volume  in quantities that small. I am lucky if I can get a +-10% repeatability.

Anyone else have any experiences or solutions? For now I am thinking I will have to weigh everything if I want any sort of consistancy.

[Santa Dave]

Seems Like a vibrating table (or something that does that) might help accheive consistancy. I had a vibrator on a powder measure and it helped a lot but that was not BP.
Dave

[GGaskill]

Maybe use Fg for light loads and save the Cannon grade for full charges.

[Double D]

Volume measures are for muzzleloading rifle and pistols,   For cartridges and cannons weigh the charges on a scale. Don't believe me look at the Cannon firing rules posted by N-SSA and AA. You will also find this in the Cannon cartridge making article posted ithe sticky's at the top of the board.

Here my set up for weighing powder for my one inch cannon.  Max load is 180 grains of Fg.

I got a 50 BMG case at a gunshow and cut the top off just below the neck. The I weighed out 180 grs of FG on a scale and pour in the BMG case.  Then I cut the case down so that it was the same height as the column of powder. I adjusted the height so it was just slightly shorter the column and would hold just a smidgeon less than 180 grains. I marked the BMG  <180 grains  FG

To use, I pour FG from my powder flask into the BMG case and dump that into my scale pan, then trickle FG with my powder trickler up to weight.  Dump the weighed powder into the plastic bag and wrap in foil.

[Rickk]

I think that is pretty much the way I will have to do it Double D. Thanks

Cannon grade is so course that is is very much dependant on how it packs, and in a small measure the packing is very hard to control. Even scraping the excess level with the top has considerable variability to it.

GGaskill, For the sake of experimentation I played with measuring 1F by volume and it was considerably more consistant. However, I would probably need less of it to accomplish what I need to do, and the charges are so light that that anything under 150-ish grains and I have issues with irratic ignition and performance.

My next mortar will definitrly have a powder chamber. Without one, shorter ranges (like 100 yards) are tricky to accomplish.

[Rickk]

Weighing every charge with my Lyman beam balance powder scale would get boring fast.

I just ordered one of these digital thingies : http://www.toplinedigitalscales.com/catalog.php?action=124&item_id=181 ... the bigger one... AWS-100-2 . Resolution is claimed to be 0.1 grains, and it will go up to 3.5 ounces.

If I was shooting much bigger bores I would look at one of their bigger capacity ones. The bigger ones loose resolution. I guess for 1/2 pound charges +- a grain isn't gunna matter much.

[Will Bison]

I went to Office Depot and asked a friend about scales. He showed me a small Postal Scale that works great.

Then I went to Lowes and picked up some copper tubing and caps. After soldering a cap on one end I measured out the proper charge on the scale and cut off the tube to the proper length.

I've checked the weight of powder poured into the measure and it comes so close it ain't worth talking about.

Bill

[Rickk]

Hi Will,

I tired both copper and PVC pipe caps and couldn't get any real consistancy.

What size charges were you messing with, what granulation powder, and what was the resolution of your postal scale?

Rick

[Artilleryman]

Gibbon's referrs to volume measures and their dimensions, however he goes on to state that if great accuracy is required to weigh the charges.  Even though it is a pain to do so, I weigh each charge.

[Rickk]

The AWS-100-2 scale showed up today. The info with the scale says accuracy is .2 grains, not .1 grains as the web site seemed to imply. Stiill, for 100-200 grain loads that is fine. It appears to be able to measure about 3.6+ ounces before it over-ranges. It has a zero feature to zero out containers. Runs on 2 AAA batteries, so no need to plug it in. The LCD display is nicely backlit for easy viewing in darker corners of ones workshed. It is small, almost pocket size, but adequate for say a paper cup or something like that for holding powder. I think it will be easier to use than a balance type powder scale.

This weekend is a major llama conference (I'm into llamas too) but I'll play with it a bit when time permits and give feedback.

Rick

[Michael Az]

Will you be using mortars or cannons to shoot the llamas?
Michael

[Rickk]

Nope, tey have me outnumbered and outgunned

[CU_Cannon]

I have a little electronic scale that I got of ebay for a bout $10.  It works great.  It has a 6 oz capacity.

[5kwkdw3]

I know that this thread is an old one, but I've had run in's with each topic presented here.  The following is a great idea and one I ended up using. 

Then I went to Lowes and picked up some copper tubing and caps. After soldering a cap on one end I measured out the proper charge on the scale and cut off the tube to the proper length.

  One inch copper tubing did the trick for me.  I also experimented with the 50 BMG cases but quickly reached the around 300 grain limitation of those.  My mortar took four cases worth and to fill level four different cases level and not spill any was a tast to be sure.  The largest load I have is a 2000 grain thunder mug and that was obtained with around 8+ inches of 1" copper soldered to a 1" NPT thread.  This allowed a street L and a plug to increase the capacity to the 2000 grains without adding 5 more inches of the tubing.  The nice thing about copper is that your soldering doesn't have to be picture perfect since it only has to hold back powder and not a liquid.  I got a set of steel stamps and stamped what device it was for and how many grains it held on the 1" end cap before soldering it on.  Really helps when shooting different loads or projectiles, or devices.  I also found a Treso valve unit and adapted it to the lid of the powder I'm using making it easier to fill these large powder measures.  I've had nothing but great success with this set up.  Smithy.

[flagman1776]

I tried various copper pipe caps...  settled with 1" for my application.  I measured the 300 grain charge I wanted & marked it, turned the cap down in the lathe slightly until I was satisfied.  I soldered a nut to the outside (after washing out the powder dust).  I used a piece of bolt to attack a wooden file handle I picked up at a flea market.  So now I have a handled dipper.
I've stopped dipping powder however.  I set the dipper in a catch container (aluminum ice cube tray).  Put a pour spout on the powder can & pour the dipper full.  Use a cardboard to strike off the top level.  Use a funnel to pour into preformed foil cartridge.  I recover spillage from the catch container & return to the powder can.