Powder Problems W/ Dillon SDB

[flyingfrog]

All,

I am loading .45 ACP on a SDB and am having some powder charge consistency problems w/ Straight Clays. If I set the weight to 4.1 I will do the six checks and get it pretty dialed in. Then after about 10 rds I will randomly check a couple and get a 4.6 or 4.4 then it will settle back down to 4.1. This of course terrifies me as I don't want that unexpected "hot" load to sneak up on me. Any one else having this problem using this powder. A friend and reloader told me that the flaky consistency of straight clays sometimes causes inconsistency. Help if you have it. OUT

[Truegent2004]

Powder variances of +/- .1 grains are common. Make sure that all of the powder comes out of the case when weighing it and that one of the powder stuck to the dispenser on stage 2.

[dillon]

A few things to check:

First, be sure the hopper is at least 3/4 full when you start. Throw about 15 charges and dump them back, then start weighing the charge. Next, be sure the powder bar is completing full travel before the handle bottoms out. The case mouth should be flared about .010" larger than a sized, unflared case. Also, be sure the return rod is completely returning the powder bar to pick up the next charge. A rule of thumb is that when you push forward on the handle, as if seating a primer, the spring above the blue wing nut should be compressed to almost, but not quite a solid.

[JD45]

I learned something about weighing charges on my SDB last month. If I ran a single case, and then removed it the charge was always 5.0grs. of Titegroup. Then I started loading normally and stopped after a dozen or so and weighed a charge, and it would weigh 4.7grs. (sometimes 4.8). I repeated this several times with the same results. So, I ended up having to open up the powder bar. With normal cycling it is dead on the desired 5.0grs., but a single case test is up to 5.3grs.. Beware of this, it would suck to load a bunch that you think will make power factor and find them way under.

[EricW]

I learned something about weighing charges on my SDB last month. If I ran a single case, and then removed it the charge was always 5.0grs. of Titegroup. Then I started loading normally and stopped after a dozen or so and weighed a charge, and it would weigh 4.7grs. (sometimes 4.8). I repeated this several times with the same results. So, I ended up having to open up the powder bar. With normal cycling it is dead on the desired 5.0grs., but a single case test is up to 5.3grs.. Beware of this, it would suck to load a bunch that you think will make power factor and find them way under.

You are experiencing the phenomena of charge compression. Which is why you always follow Dillon's procedure (listed above) for sampling your charge weight. This is also why you always dump your first few charges before starting up loading after a delay - especially if you dry cycle or bump the press at all during that delay.

The phenomena affects ALL volumetric powder measures. It is not peculiar to Dillon's.

[TBF]

Good advice above.

After getting the desired setting on the measure,

Be sure to pull a case from the loader to check during ACTUAL OPERATING CONDITIONS, things change , sometimes alot, between single charging cases and a fully operational press, running at normal speed.

I load some and check at the bullet seating station after getting to full steam.

Throw these " warm up " rounds in the " for shooting really fast " box.

Providing that the measure was set pretty close to begin with, and this seems like a safe thing to do.

Travis F.

[kimel]

I have a rule that I check the charge when anything runs out. If primers need to be refilled then I check a powder charge. If the bullets in the tray run out, I check a powder charge. If I have to spray down more brass with One Shot, I chedk a powder charge.

This is kind of a left-over from when I was trained to reload on a single-stage oh those many years ago.

Over the past year or so with my SDB and Titegroup I have seldom seen much variation.

I also use dry lube on my powder bar (Krunch Mag Slick) and that REALLY helps a lot.

When I first got my SDB the blue nut on the down-rod would work itself loose and things would go crazy. A good whack with a calibrated hammer on a calibrated punch aimed (in a calibrated way of course) at the nut fixed that.

[benos]

In addition to Dillon's recommended technique, a good practice is to always weigh the total of four charges thrown from the measure before attempting to adjust it. Once you get used to doing this, you'll not only dial the measure in more quickly, but you'll have less headaches as well because you'll stop worrying about minor charge-weight variations. You might even make a handy chart, with "four-charge-totals" for your favorite loads, and keep it near your scale.

You can do this fairly quickly on a 1050. Once "ready" to dial in the measure, stick a 38 Super case between the roller in the Casefeed plunger and the and the Casefeed frame assembly (which prevents new cases from entering the shellplate), then run the shellplate empty. Stick a primed case under the Powder Measure and cycle the handle, but pull the case out of the station before the case begins to index to the next station. Then, if you can get two charges in the same case (like with most .40 loads), stick the same case right back in the station and dump another charge in it, then snag the case and pour both charges in the powder pan. (If you can't get two charges in the same case, you'll figure it out.) Repeat, and now you have some useful criteria with which to calibrate your measure.

It's super easy on a 550, and I'm sure someone will post how to quickly stop cases from entering the shellplate on a 650.

be

[uscbigdawg]

One thing that I've found to help eliminate powder charge variations on all my progressive presses (650, 1050 and 9000G) is to dial everything in with the stations occupied with shells. I don't know why. Call it the shellplate settles lower or whatever, but when I set up my powder measure with brass and bullets at the various stations, when the loading goes and I check my charge weights, they are within .1-.2 of a grain (I didn't belive it until I was getting loads with SD's under 5 for .38 Super on my 1050).

The big lesson that was taught to me by 'dear ol' Dad' was consistency. Whatever you do on a press (single stage or progessive) do it the same every time and that in and of itself will yield more consistent ammo. When I watch him throwing rifle charges on his RCBS, the 'tink....tink' of the powder measure is the same every single round and is why he loads great ammo.

Rich

[MemphisMechanic]

It's super easy on a 550, and I'm sure someone will post how to quickly stop cases from entering the shellplate on a 650.

be

Here's what I do on a 650: (Say you're at 3.0 grains, and want to be at 3.2 grains...)

1. Empty the cases from the shellplate, turn off the casefeeder, and empty the casefeed tube.

2. Turn the knob up slightly to increase the charge.

3. Stick a piece of used brass in the shellplate at the priming station.

4. Run the shellplate up to charge it.

5. Drop the handle. Pick the case out of the shellplate as it indexes, move it back to the priming station, and fill it again.

6. Pull the case, and dump those two charges back into the hopper.

7. Repeat again. I want the press to dump at least 4 charges after an adjustment.

8. Repeat the previous steps, but dump the powder onto the scale, instead of back up into the hopper.

Weigh 4 charges, and divide the total by 4. I like to see 12.9 if I'm shooting for 3.2 grains, so it's a hair over the actual weight. That way your rounds that are a tenth lighter, are closer to your desired charge weight.

I'll then randomly weigh a charge after about 20 rounds, and after 100, and whenever I feel like it after that. Anything between 3.1 and 3.3 won't cause me concern. One charge on a digital scale isn't a terribly precise measure.

Edited January 5, 2009 by MemphisMechanic

[D. Manley]

"...Weigh 4 charges, and divide the total by 4. I like to see 12.9 if I'm shooting for 3.2 grains, so it's a hair over the actual weight. That way your rounds that are a tenth lighter, are closer to your desired charge weight.

I'll then randomly weigh a charge after about 20 rounds, and after 100, and whenever I feel like it after that. Anything between 3.1 and 3.3 won't cause me concern. One charge on a digital scale isn't a terribly precise measure."

My routine is similar except, for final tuning I'll throw 10-charges and average. Yes, it takes a bit longer to set up but youmight be surprised how consistent the measures can be when finely dialed in. Once I get a couple of 10-throw averages "spot-on" I don't bother to check again until after 100 rounds (primer fill) or, if I get interrupted for some reason. Following this model with a variety of powders its very rare to check a single throw and find it off at all and even then, never more than a tenth.

[kevin c]

Lots of good tips above.

Another one that seems to help me w/ Clays, which is a light flake powder that "settles" in and which might "bridge".

I got an inexpensive aquarium air pump and fastened it to the side of the powder measure with a few heavy rubber bands. Running, it makes the measure vibrate slightly, and I think my powder drops (after the first 10 or so) are more consistent.

[RePete]

I was reading another thread concerning inconsistant charges dropped from a Dillon powder measure, and started to think on what would/could help with consistant throws.

The low powder sensor came to mind, but not to detect low powder.

The tool consists of a disc on top of the powder, a rod throught the cap and a weight on top of the rod. The weight may not be heavy enough but that's a easy fix. The idea is to place a constant pressure on the powder. Yes, when full, there would be more pressure due to the added weight of the powder column, but as the column gets shorter so does its weight.

[benos]

I tested this many times over on a 1050 with Clays powder - the charge weight, with a full Powder Measure, and the charge weight, with the measure almost completely empty was the same.

be