Show me your BPCR drop tubes!

[Froogal]

Put your 1.66cc into a shell. Now pick up the shell and tap it lightly on your bench 20 times. You will now see there is extra room in the shell for more powder. This is the effect that trickling down a long tube has...it allows the powder to pack closely together rather than having air spaces between the kernels of powder. Putting that shell on a vibrating surface will give you the same effect.

Some amazing workmanship, guys. I am impressed!

Yes! That is exactly how I determined that 1.6cc was sufficient.

[Captain*Kirk]

Yes! That is exactly how I determined that 1.6cc was sufficient.

Well, that being the case, all I can tell you is that trickling powder down a drop tube allows more into the case than pouring from your scale pan or a powder measure.
Try it and see.

[rfd]

drop tubes are all about powder *compaction*. the wad/powder compression comes next.

[Markopolo]

Oh My Brent.... it is Aliveeeeeee.. very interesting..

[MOA]

Yes, this is an original black powder measure manufactured by Ideal in 1893, when black was the dominant powder in use. This powder drop will need to have a substantial vertical support that will incorporate the attachment of the powder measure. This measure is made of cast iron and brass.

[kokomokid]

Built one like Brents because I like to tinker. Have different funnels for each powder size. Example is delrin plugged funnel drilled out to .090 for swiss 3f . Have a mirror to see when the powder is all dropped.

[BrentD]

The mirror is an excellent upgrade!

May the next guy try a Bluetooth camera or a hovering drone.

[Edward]

Mine is simple 82 grains of OE 1 1/2F in my starline brass and the vibrator does triple duty works on compaction/ making designs on hair on deer hides/and my beard gets trimmed (infrequently) Ed
Attachment 238962

[mazo kid]

I threw this together a few years ago to check out how it worked. Wish I had spent a little more time to make it look better, but it is what it is.

[MOA]

Mazo, if it works, it's always a beauty.

[BrentD]

Sometimes, the hardest part of a drop tube is finding the funnel. My double funnel system has a plastic reloading funnel from the local gunshop, but the aluminum funnel came from a friend and I don't know where it was sourced.

Anyone out there have a good source for an aluminum or brass funnel?

[MOA]

Sometimes, the hardest part of a drop tube is finding the funnel. My double funnel system has a plastic reloading funnel from the local gunshop, but the aluminum funnel came from a friend and I don't know where it was sourced.

Anyone out there have a good source for an aluminum or brass funnel?

I got a couple of aluminum funnels online from ACE hardware a few years ago. I ordered three I think just because you never know when you won't be able to get them easily anymore.

[rfd]

i found my aluminum funnel in a local craft store for about $4. ebay has assortments of aluminum funnels, but pricey in the $20+ range.

[Captain*Kirk]

I threw this together a few years ago to check out how it worked. Wish I had spent a little more time to make it look better, but it is what it is.

Mazo, looks great to me! I like the idea that you used a shellholder in the base...looks rock-solid.

[mazo kid]

Thanks Kirk, the shell holder is held in place with a set screw but it doesn't show well in the photo. I made my own funnel from thin brass sheet with a piece of copper tubing flared to help keep it in place while soldering. The "adaptor" to join the funnel to the drop tube is a cut-off piece of cartridge case, neck fits snugly in drop tube, funnel snugly in the body.

[Bent Ramrod]

You can get an idea of the degree of compaction by filling a couple shells both ways and then slowly turning them from vertical to horizontal over a dish. Depending on grain size, glazing and coarseness, you can usually tilt the tube-trickled loads a few degrees more below horizontal than the dumped-in charges. The former kind of lock together and come out in a heap, while the latter start pouring out as soon as you reach horizontal.

My drop tubes aren’t worth pictures. The cartridge loading one is two leftover pieces of copper swamp cooler tubing straightened out by pounding a steel rod through them, soldered together, with a scrap of copper sheet curled into a cone, soldered and soldered to the built-up tube for a funnel. I use a buret holder to hold it upright. Hideously ugly, but all that’s needed. The more elegant one is a carbon-fiber arrow shaft I found, pushed the end through a one-hole rubber stopper and the stopper crammed into a green RCBS powder funnel. I use that to trickle load my Parker-Hale Volunteer Rifle.

I search for paper joggers now and again; they would be great for compacting powder, but most of the ones I see, even used on Craig’s List, are ridiculously expensive. Used to use them at Work for getting the air bubbles out of propellant mixtures. Put a little vacuum over the container, start the buzzer, tune it to the right vibration mode, and the stuff would fizz like Alka-Seltzer. I would expect it would get the empty space out of a column of powder the same way.

[dirtball]

Simple, effective, 35" drop, took 15 min to build.

[MOA]

They say a picture is worth a thousand words, so...
Let's see some pictures of your BPCR drop tubes!
Gonna be loading soon for .45/70, and possibly .44-40 WCF in BPCR, so need to concoct a drop tube. I have a pretty good *vague* idea of what I want to build, but actually seeing what works for others usually saves mistakes, headaches and wasted materials as well.
Whattya got?

Here's the start of the new powder drop made with 1/4" ID copper tubing. I've decided to do a spiral tube using a 2" rolling pin as the form. This will give me a 34" tube drop in a 22" distance. I took a large sheet of paper and drew a line at a 45 degree angle that was 34" in length and then rolled it around the 2" rolling pin so I could follow the line around the form with the copper tube. The tube angle should stay at the 45 degree angle which should allow the powder to fall and compact at the bottom. The tube was crimped at one end and then filled with solder and then the tube was filled with water so it would not collapse when being wound around the form. The other end was crimped but not soldered, I didn't think enough water would leak out while winding the form to collapse the form, and I had the un-soldered end up at the top and not at the bottom,(which it didn't when I wrapped it.) The top was taped to keep that section straight and the bottom end was also kept straight to facilitate the pour. I now can measure how long the vertical support needs to be and put together the base support and all the tube clamps. More images to follow. See the Projects thread for the images of this build and the completion of this BP spiral drop tube.

[BrentD]

MOA, I think the spiral defeats the purpose of a drop tube, but maybe not. I'd like to see powder column heights for that AND a 22" straight tube.

[MOA]

MOA, I think the spiral defeats the purpose of a drop tube, but maybe not. I'd like to see powder column heights for that AND a 22" straight tube.

BrentD, you might be correct, but I won't know til I try it. The velocity of the powder may not be high enough to compact it like a straight tube will. I'll have a better idea tomorrow when I start so see how it flows through the spiral. Hopefully my fried right thumb is usable. I inadvertently got my thumb into the torch flame for just a second while trying to get some solder into the crimped end when the tube turned and I reached for it. Ouch bigly. So tomorrow I will have a idea how it drops. Stay tuned.