Stock Powder Drop Expander or Dedicated Expander Die

In my opinion, the real problem is the Dillon powder measure.  Whether you expand with the powder drop or not.  Why?  It leaks powder, enough to require constant cleaning.  The expander “bells” the case mouth making it resemble a trumpet.  This just overworks the brass and expand depth is not easily adjustable.  The adjustment for powder quantity is held by spring induced friction and can move and there are few indications on how much you’ve moved it so “dialing it in” is tedious.

Swapping this measure out to a Hornady or RCBS with the case activated powder thru expander systems eliminates these issues.  Hornady sells extra measuring inserts so once you dial in your load you can swap the measure quickly for your favorite load.  A good number of the precision (CMP/NRA, PRS) rifle shooters have swapped.

There are aftermarket expanders and measuring bars that alleviate some of these problems but there is always the leaking.

I've not had any issues with using the powder drop expander. The after market style expanders do a very admirable job as they incorporate a step in them to aid in seating the projectile straight without needing excessive belling.

I have three Dillon machines and have loaded tens of thousands of rounds and have not experienced any of the issues mentioned above.

For me, it depends a bit on what caliber you plan to reload?

For 45, I use all the stock Dillon components with none of the issues noted.  For smaller calibers, particularly 32 long and 32 ACP I use a couple aftermarket products.  UniqueTek sells many many aftermarket products for Dillon reloaders, I like the micrometer powder measure for the small (less than 2 gr) amounts of powder involved with this caliber.  i found it more consistent than the stock Dillon unit.

I also highly recommend the two stage powder thru dies that Photo Escape makes, I find them far superior. 

Re: powder leakage, I do not notice this with the stock Dillon unit.  On one of my 550s I have the plastic Arredondo powder slide, and it does leak a very slight amount with VV310, but not enough for me to worry about.  Many find the Arredondo superior, my results may not be representative.

On my Dillon SDB and the Dillon X-small powder bar I get powder leakage using Bullseye. This is loading .32 S&W long with 1.6-1.7 grains of BE. I do prefer the Hornady measures on my 2 LNL AP presses, they don't leak and I like the interchangeable powder stems.

A friend has a 550 Dillon and during a 223 loading session using 748 powder she was constantly brushing away powder from the shell plate.  The powder was denting the primers.  Swapped out the measure with a RCBS and case activated linkage and the issue went away.

With Dillon, you have to add dwell time for rifle rounds, as there is a considerable amount of powder that has to crawl through that small bore in the expander and into the necked down case.

You can't just keep cycling the handle as you can with pistol loads. (Or it spreads powder all over the shell plate!)

I don't get how people find reasons to alter a 550/650. I've used one to get double distinguished, shoot high master 600 yard service rifle, master 50 yard scores.
Even my 32 long 50 yard shots are on call.

DA/SA wrote:With Dillon, you have to add dwell time for rifle rounds, as there is a considerable amount of powder that has to crawl through that small bore in the expander and into the necked down case.

You can't just keep cycling the handle as you can with pistol loads. (Or it spreads powder all over the shell plate!)

That is absolutely accurate!  More so, I also recommend tapping on handle few times to avoid bridging, which is very typical with extruded powders (i.e. Varget).

And that is the reason, you will not find any of my PTUs (Greg, Thank you for mentioning about my expanders) for calibers from 20 to 25, - internal diameter of the expander is too small for powder to get through.  I tried making batch for 243, and it didn't work.

Reloading is all about hands on and my motto is "Try, Fail, Think, Try Again, Fail Again, Think Again" and so on until solution is found.  Yes, some of the Dillon measures leak even at no fault of reloader.  Primary the culprit is powder bar housing.  It is aluminum cast part with very little post processing.  The good news is that it take less than five minutes to address.  All one would need is piece of flat wooden plank cut to slightly smaller width then powder bar and 600-800 grip sand paper.  After about dozen strokes back and force, you done.  If you want to go extra mile (as I do), you also can put sand paper on flat surface and do few strokes over it with both sides of powder bar (and insert for small and x-small bar).  I also do some polishing with Flitz and Simichrome, but that is just because....

AP

Won't sanding the powder bar housing and powder bar just increase the total slop and allow it to leak even more?

The object is to only remove the high spots/burs. 

Very fine paper on a surface plate or other hard flat surface.

You don't want to "sand" it enough to decrease the thickness, you just want to increase the surface contact where the parts meet.

zanemoseley wrote:Won't sanding the powder bar housing and powder bar just increase the total slop and allow it to leak even more?

I believe (was told) the idea with the Arredondo slide is that it is made a bit oversize, and then is sanded down to fit.  I have 8 tool heads, and when I mic’d them there is definitely some inconsistency. With fine grain powders some leakage “might” occur, just depends on the gap. Lee at UniqueTek mentioned this to me, and suggested measuring and then matching to get best results. I only noticed leakage with VV310, and only with 32 caliber and the Arrendindo slide. Following Lee’s advice and using a different housing I was able to reduce the leakage to diminmus.  You are correct, if it’s already leaking, sanding will only make worse. 

I think this is why some notice the issue, whereas most don’t.

As for rifle dwell time. She is an accomplished reloader.  She didn’t have the problem when loading 30-06 using a different Dillon measure. And the funnel diameter on a 223 funnel for the Hornady is the same.  So?..?  And 748 is no where near as fine as 296 which people complain about leaking a lot.

To the original OP, from your "Drunken" Uncle Cecil:

The Dillon or replacement powder through expander will work just fine for belling the case for pistol reloading.  

There are a couple of things I use as guidelines when I see questions like this from new shooters / reloaders. 

(1)  If it works, it ain't broken or need'n to be fixed.
(2)  Most times, trying to make something better doesn't (at least the first time). 
(2)  If it don't work, make sure you understand exactly what the problem is before you start fix'in something in order make sure it's the right something. 
(3)  In any event, if you ain't smarter than the thing you're working on, stop and get smarter before doing anything else.

I've seen a lot of people waste a lot of time and money on guns, reloading stuff, etc., that they started working on or adding stuff to, or just plain modifying and changing (even if there was not a problem or issue) because somebody said they had a problem with whatever they had.   

Remember the exception is not the rule and most times its the user, not what's being used.

Proceed with thoughtful care and caution.  

CR

I don't want to get deep into science, however each powder measure is using powder flow characteristics.  Think of it as a viscosity for liquid.  In short, movement of powder must overcome various friction points depending on direction.  With powder drop from up down, friction between powder particles is insignificant, and this is how it flows through the funnel down into the case.  When powder moves horizontally, friction between powder particles among themselves is much higher then between powder particles and metal surfaces of powder bars. 

If you apply the above to mechanical workings of Dillon's Powder Measure, it would be obvious that, unless sanding and polishing is overdone, it would otherwise help alleviating of leaks.  In case of small bar powder column is being held in place by insert while sliding on top of the powder bar.  In case of large powder bar, it is held directly on the top of the bar.  Remember that powder measures are free flow type devices, there are no spigots to close and open.  Physical properties of powder are used to hold it in place.

As for spillage while loading 223, - I have it too, although probably in much lesser quantity.  IMO issue is with precision of the manufacturing of the parts.  223 funnel is open ended.  When case is inserted into funnel, top of it pushes funnel up.  There is no any kind of alignment between funnels ID and case.  Powder particles are small enough to get cut on top edge of the case.  When case is extracted these particles have equal opportunity to fall inside or outside of the case.  And then there are also some particles that got caught at the upper portion of the funnel.  That is another reason I tap few times when handle of my 650 is all way down while loading 223 and other bottleneck cases.

AP

For an engineering perspective... https://www.brookfieldengineering.com/learning-center/learn-about-powder-flow-analysis/what-is-powder-flow-analysis

But most Powder measures are designed around core flow.  

A difference between a drum measure and a slide measure is a drum naturally drops over a time where a slide seems to dump all at once.

Greetings Wobbley,

The link to the paper was interesting.

Do you know of the ideal shape of the cavity to dispense powder?

Cheers,

Dave

Wobbley,
From engineering perspective, I respectfully disagree with your statement, that Powder measures designed around core flow.  I am of the opinion, that Dillon powder measures designed around Mass flow.  (Great article, thank you for the link!!)  Powder funnel is just a transfer component of the equation.  Powder hopper is actually component that initiates the flow.

Dave,
Best shape to dispense anything, that flows using gravity (powder, liquid, sand, etc.) is a cone (one of the variation can be a pyramid)  or bell.  For the sake of discussion, I should say, that this is "in my opinion".
AP

Dillon and other measures use baffles to disrupt the flow.   It those that don’t have baffles installed seem to follow core flow more often than not.  The powder uppper surface gets a dish shape to it.  If it was mass flow they wouldn’t.  Years ago we used to attach vibrating devices and give them a burst from Time to time to settle the flow.

I second the Powder Transfer Unit from Photoescape.  Helped solve my 9mm problems. Much easier to place bullets straight with no wobble.  Have them for all my calibers now.