SDB Powder Measure problem

[Randy C]

I've been loading on my Square Deal B's for the past 15 years. I have one press set up for 9mm and the other SDB is set up for .45ACP My 9mm is now throwing double charges every few rounds. I'm runnning 5 grs. of Unique and have always run Unique in both presses. A normal 5 gr. charge takes up approx. 3/4 of the casing and is very easy to monitor against double charging. During my last reloading session, I caught a couple of casings with double charges which of course overflowed and made a mess. I've never had this problem with either of my SDB's before.

Has anyone else had this problem with a SDB and what can I do to fix it?

Thanks

[kimel]

Sounds like your shell plate is not indexing.

There is no physical way the measure can throw a double charge and then go back to throwing a single charge unless the powder is getting hung up somewhere and you have a bunch of under charge rounds right before you get the double charge OR the shell plate is failing to index.

I'd guess that the indexing mechanism in the ram has either worn or loosened to the point where it can miss indexing now and then. Or, it is full of crud (lube and powder) and not indexing properly.

Whenever my SDB starts to act funny I do a total tear down and clean it up with a wary eye open for any worn or broken parts. That has solved every single problem.

Failing that call Dillon and see what they have to say.

[dillon]

I also recommend removing the powder measure, use a cotton swab with solvent to clean the interior of the powder funnel and the steel

drop tube pressed into the bottom of the powder measure. It does sound like the shellplate is not consistantly indexing, though.

Remove the shellplate (but not the disc underneath), clean everything, inspect the index pawl and lube the pivot points with grease.

[Randy C]

Hey guys, thanks for the information.

[benos]

If the Shellplate didn't index, wouldn't that be too obvious not to notice? Wouldn't you end up with a bullet in your hand, but "no place" to put it? (A loaded round would be in the bullet seating station.)

be

[Randy C]

If the Shellplate didn't index, wouldn't that be too obvious not to notice? Wouldn't you end up with a bullet in your hand, but "no place" to put it? (A loaded round would be in the bullet seating station.)

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Brian

The shell plate does index properly. I first noticed the malfunction at station 3.

Even with the failsafe powder drop system, I visually check my cases before seating the bullet.

5 grains of Unique is very easy to see, almost filling the case. A couple of rounds will be fine, then round number 3 will overflow. I then get another good round, then one that overflows.

I've had SDB's for a long time. I've never seen this problem before.

Anyway, I'm planning to take the press down this weekend, check the powder/expander dye for proper function, then give it a good cleaning.

Thanks Again!

Randy

[Randy C]

I cleaned everything up including the powder drop/expander die. Everything is working fine now!

[JThompson]

I cleaned everything up including the powder drop/expander die. Everything is working fine now!

Still wondering what caused it.....

[D. Manley]

Still wondering what caused it.....

Me too. I wouldn't have thought it possible if it's indexing OK and if it were a "bridging" problem, looks like there would be some pretty severe undercharges as well.

[Randy C]

One of lifes little mysteries, I guess.

5 gr. of Unique will fill a 9mm casing approx. 3/4 of the way full. When I cleaned the press I found quite alot of powder that had overflowed and ended up under the shell plate. I had 3 cases over flow. I figure well over 6 gr. of powder was dropped causing the overflow.

I don't cycle my press very fast. I visually check each case at station 3 assuring powder drop consistency before I seat the bullet. If my press wasn't indexing, the casing wouldn't have made it to station three. Even with the powder build up under the shell plate, the press continued to index.

I loaded up 200 rounds today. The press is working fine.

[slavex]

did you check to see if the case's you noticed the extra powder in actually had extra powder? I've had more than a few cases with bits of paper in them (even after tumbling) that would made it look like there was extra powder when in fact it was just crap under the powder. if you actually had double charges, and your shell plate was indexing properly, then you have some squibs or low powder rounds that made it through your reloading.

[Randy C]

did you check to see if the case's you noticed the extra powder in actually had extra powder? I've had more than a few cases with bits of paper in them (even after tumbling) that would made it look like there was extra powder when in fact it was just crap under the powder. if you actually had double charges, and your shell plate was indexing properly, then you have some squibs or low powder rounds that made it through your reloading.

I removed the three cases at station three when I found them over flowing. I thought foreigh matter may have been the culpret until I dumped each one into my scale and they were way over. No foreign matter was found, only gun powder. I also visually checked the insides of the cases. That particular press has been in service since 1994. I never had that problem with either of my 2 SDB's and outside of those 3 cases, it hasn't happened again.

[slavex]

then you must've had powder bridging inside the drop tupe. perhaps it was just building up on some debri in the tube, and then when it reached critical mass, it would break free and drop into your case. if that's what happened you probably would've never noticed low powder in your other cases. but I find it hard to fathom that something like that could happen. the other possibility, and more likely in my opinion, is that you had clumping of some form with the powder, which means you would've had some loads with very low powder charges. if the shell plate was indexing, then it would physically impossible for the measure to throw two charges into a case.

[dillon]

How much are you flaring the case mouth? It needs to be at least .010" larger than a sized, unflared case to ensure the powder bar is fully actuated.

Failure to do so means the powder bar drops inconsistant charges, and you won't know how much the powder bar is trying to dispense. Could be the bar is actually set to dispense a greater charge than is dropping into the case, and incomplete powder bar actuation is not showing it in some weighed charges.

[slavex]

ooh there's another possibility!

[Randy C]

How much are you flaring the case mouth? It needs to be at least .010" larger than a sized, unflared case to ensure the powder bar is fully actuated.

Failure to do so means the powder bar drops inconsistant charges, and you won't know how much the powder bar is trying to dispense. Could be the bar is actually set to dispense a greater charge than is dropping into the case, and incomplete powder bar actuation is not showing it in some weighed charges.

Thanks, that does make sense. I was running 5.5 gr. of Unique, then reduced the charge to 5.0 gr. I needed to turn the adjustment screw several times for the 1/2 gr. drop. That didn't seem right to me. I'm going to increase the flareing and see if my charge weight increases. Maybe this mystery will finally be solved.