Dillon powder funnel & expander

[Cherokee]

99% of my handgun reloading is with cast bullets and I have not been pleased with the Dillon factory powder funnels case expanding results because the dimensions are designed for jacketed bullets. I have had to separately expand the cases using Lyman M dies before loading on the Dillon 650 or 550B, I think some comments by members 358156hp and Brad, as well as there being aftermarket products, indicate people are aware of this. However, the aftermarket examples I have still do not completely satisfy. Below is a picture of the three aftermarket examples I have, A,B & C from left to right.

A – For 45 ACP. The body is .450” and the M step .452”, but will not flare the case mouth.
B – For 9mm. The body is .355” and the M step is .357”, but will not flare the case mouth. Also, the length of the .355 body is too long for 9mm, it bulges the case below the bullet base.
C – For 38/357M. The body is .355” and the M step is .357”, and will flare the case mouth. However, the length of the .355” body is short, like for 9mm rather than 38/357.

I like the design of C except for the shortness of the .355 body, which I think should be .356. Since all my 38/357 cast bullets are of .358 size, I would think an M step of .358 or .359 would be better. I do not understand why an M style like A & B would not also be capable of putting a flare on the case mouth like C.

I would appreciate thoughts from the members.

 

[Brad]

If the bullet started square and isn't shaved on seating then A or B would be good.

I agree that expanding the case below the base of the bullet isn't needed.

I need to think hard about this then try making one. I don't think the groove is required at the top for a 550, that makes it a bit easier. Making the step like an M die is easier in ways than a taper.

Any idea what those are made of? They look like they were heat treated.

 

[Cherokee]

Brad - I have no idea what steel they were mode from. A&B have been heat treated for sure. Do you think the heat treating is necessary ? Since the funnels might be used in the 550 or 650, I would need the groove.
Tests with the B indicate a flare is needed to avoid shaving. I think this would apply to A as well.

 

[Brad]

A slight flare isn't hard to do.
As for heat treating, it wouldn't hurt. I would think that after thousands and thousands of rounds are loaded there could be some wear otherwise. Might be able to use a tough enough steel to use it annealed? This is a good question for smokeywolf, he is the machinist .

 

[358156hp]

I'd heat-treat them. While the case is soft brass, the die they run in is steel, as is the funnel from the measure IIRC.

 

[Brad]

I'm far more concerned with wear on the actual expanding section. Over time if it wears the neck tension changes.

 

[Mikey]

Mind if I spitball with you a bit on this subject?
I've only recently been introduced to the concept and benefit of the M die (Horrors!), but still haven't used one, or seen one, or touched one, so maybe y'all can help me out, and maybe I can devil's advocate my way into being helpful as well. I too would like to build the perfect powder funnel/expander for cast bullets, but I'm having trouble wrapping my head around a couple things. BTW, I use an old RL-450, which uses the same funnels as the 550, so it should be apples to apples.
1. If you want to accomplish the M-type expansion AND a slight mouth bell, won't the expander portion and the flaring taper BOTH have to be customized to the seating depth of a specific bullet? i.e., I have a .357 bullet with 2 crimp grooves (or I just have 2 different bullets with different shank lengths). If I want to crimp in the top groove, I need to expand the case to accept .395" of bullet, the lower crimp groove only uses .305" of case depth. I can't imagine that I want to expand the extra amount of case, but otherwise I won't hit the flaring taper, nor will I actuate the powder measure proper. Correct?
2. How much case expansion is proper to achieve adequate case tension? If the bullet is sized .358", do I want the internal case diameter sized to .358 as well? Doesn't sound right, but maybe I'm overthinking it. Seems like .357 or .356 would be more appropriate. I don't know.

And I think you're right, Brad, the groove at the top of the funnel doesn't seem to have a function in our type of setups; I used to think it was stepped there, but the tube O.D. is the same above and below the groove.

mike

 

[Brad]

I want .001 or so neck tension on the bullet. Problem with stock funnels is that Dillon makes them for jacketed bullets. A 9 mm is designed for a .356 jacketed bullet so the funnel might expand to just .355. We might want to use a .358 cast bullet and the extra neck tension can squeeze our .358 bullet to .357 in some situations.

Bullet length inside the case can be an issue if we use widely varying bullets. I see this as more of an issue in a short case like 9 mm than I do in something like a 38 special.

It comes down to a pretty simple thing really. We can either have a variety of funnels with each being set up for a specific bullet or we can make a funnel that is a jack of all trades but may not be ideal for any.

 

[fiver]

or just make your boolits 359 and let the brass squish them down to 358.

 

[Cherokee]

Mikey - Thanks for joining in. For straight wall cases like 38/357, 41, 44, 45 a body length for a typical bullet would work for me; having the body expanded deeper than necessary for a short bullet length is not a problem to me; its the less deep than bullet length that potentially gives problems. For the 9mm I want a short body but sufficient for the cast bullet being used. I too want .001-.002 under bullet size for neck tension and .002 over bullet size for the short M-step.

My factory funnel for 9mm expands to .353 and the 38/357 one expands to .354. OK for jacketed with a proper flare, not good for cast because of excessive neck tension for .356, 357 or 358 cast bullets in either cartridge.

Fiver - you have a point, but starting with a 359 bullet makes the need for case flare more drastic in order to avoid shaving the lead, and I think the result could be inconsistent.

Brad - I looked at the way the funnel interacts with the measure and don't see that the groove at the top has a function for the 550 or 650; wonder why Dillon puts that groove in ?

Good comments, keep them coming....

 

[fiver]

the groove is there cause the 450's locked the funnel in place and you dumped the powder by hand.

 

[Cherokee]

Fiver - Thanks for the info, so I don't need them.

 

[Mikey]

I found an online article about a guy's ideas for improving the M die system. It had pictures and explanations that I found helpful for understanding the concepts we're dealing with here. I'll post the link to the first article (there is a Part II as well) for anyone interested; his company is Beartooth Bullets, located in the part of Idaho that is nearly as far as you can go without a passport... and his name is Mike. Mike... Idaho... bullets... guy has to be a genius!
Anyway, his idea boils down to piloting the expander at internal, resized neck size, then the "M" step, then adding one last, teeny step at the top of the stroke (.050" long) a couple thousandths larger than bullet diameter to give you an aligned starting flare. Then just ironing that back into place after seating with a FCD or taper crimp. Certainly wouldn't be enough room in a 9mm-like case for much initial piloting, but the whole concentricity issue appeals to the truly anal part of my thinking. His double-starter expander button idea for bottleneck cases has some appeal as well.
http://www.beartoothbullets.com/tech_notes/archive_tech_notes.htm/39
I really need to stop thinking about this... I have way more other things that need to get done today, other than chucking up a piece of round stock and playing with these ideas for a Dillonesque funnel.

mike

 

[Cherokee]

Mikey - good information, thanks for the link.

 

[Cherokee]

Well, I have this 6" length of 30 cal barrel and a HF 7x10 mini lathe. I'm going to see if I can make a funnel for 38/357. I'll need lots of luck....

 

[Brad]

I have some steel coming soon. I want to see if I can whip one of these up too.
Nothing ventured, nothing gained.

Let us know how it goes Cherokee. I'm pulling for you.

 

[Cherokee]

I turned the barrel to near the diameter I need (.550") and cut off a length for the funnel, next is cutting the spud...that will be fun...

 

[Cherokee]

Its done and works. My machining skill...uuun ability, definately not skill, shows but it does work. Demensions did not end up exactly what I wanted but it does work. A few pic's along the way:

Turning the 30 cal barrel down to size, I wanted .550 but ended up with .556

Next was turning the spud to basic size, then cuttng the steps

Had to taper the powder measure end

The final product on the left next the facotory funnel:

I ran a few test cases thru the 550 and it seemed to work fine, expanding the case and putting in an M step that allows for seating the .358 size bullet. Real test will be to load some later this weekend. Then I'll try to make another one closer to the desired sizes.

 

[Mikey]

Looks good, and you didn't need any luck after all.
What did you end up with for the measurements of the different steps?

mike

 

[Cherokee]

Thanks Mikey, but I had plenty of luck considering my lack of ability and experience using the tools. The measurements did not come out like I wanted but will live with it until I get around to using the remaining stock to try to make a better one.
The expander body ended up .353 when I wanted .356; I was heavy handed in the final cut and took off too much. But the length of the body is the same as my cast 358158FN Lee, my longest CB.
The M step ended up .365, I was shooting for .360; I could take it down some but initial tests indicated even .365 was a tight fit for hand placing the .358 size bullets on the 550B.