50 drops - Lee Auto Drum Powder Measure

[LiveLife]

Good morning,​

​

... I would not be surprised to see the results get better as the drum continues to be conditioned and break in. We often see the best results after a pound has been ran through any powder measure ...​

Calvin Katzfey​

Lee Precision​

As indicated by email from Calvin, I ran some W231/HP-38 through the Auto Drum with a new cone before conducting the 50 drop test. You can see that the elastomer wiper has blackened to be "conditioned".


Powder measure was reassembled with light pressure on the wing nut so there was no slop of cone. Hopper was filled with W231/HP-38 and lightly tapped 20 times to settle the powder. About 10 charges were dropped before starting 50 charge drops with target of 5.0 gr.

Creedmoor Sports TRX-925 digital scale was used after power on auto calibration without any warm up. Auto Drum was mounted in station #2 of 2023 Breech Lock Pro 1000.

1. 5.00 gr
2. 4.99 gr
3. 5.04 gr
4. 4.96 gr
5. 4.98 gr
6. 5.03 gr
7. 5.01 gr
8. 5.00 gr
9. 4.96 gr
10. 5.00 gr
11. 5.02 gr
12. 4.95 gr
13. 4.98 gr
14. 5.02 gr
15. 5.02 gr
16. 4.96 gr
17. 4.98 gr
18. 5.02 gr
19. 4.99 gr
20. 4.96 gr
21. 5.04 gr
22. 4.99 gr
23. 4.99 gr
24. 5.03 gr
25. 4.95 gr
26. 5.00 gr
27. 4.95 gr
28. 5.03 gr
29. 5.01 gr
30. 5.03 gr
31. 5.00 gr
32. 5.04 gr
33. 4.97 gr
34. 5.04 gr
35. 4.99 gr
36. 5.05 gr
37. 5.02 gr
38. 5.02 gr
39. 5.03 gr
40. 5.01 gr
41. 5.02 gr
42. 5.04 gr
43. 5.02 gr
44. 5.00 gr
45. 5.05 gr
46. 4.98 gr
47. 5.04 gr
48. 4.98 gr
49. 5.02 gr
50. 5.04 gr

Breakdown of charges:

• 6 charges of 5.0 gr (On target)
• 8 charges of 4.99/5.01 gr (.01 gr from target)
• 14 charges of 4.98/5.02 gr (.02 gr from target)
• 6 charges of 4.97/5.03 gr (.03 gr from target)
• 11 charges of 4.96/5.04 gr (.04 gr from target)
• 5 charges of 4.95/5.05 gr (.05 gr from target)

50 drop spread was 0.10 gr with 45/50 drops within 0.04 gr from target.

 

[badkarmamib]

I must have been doing something wrong. I was either all over the place on charge weight, or dumping powder everywhere when I ran HP-38 through a Lee drum. Switched to the disc and seemed to do better. Truly glad it works for you, wish I had the same experience, would have saved a lot of headaches.

 

[ericuda]

Nice results. Did you do anything like tap measure or did you just do 50 drops.

 

[LiveLife]

wish I had the same experience, would have saved a lot of headaches.

Nice results. Did you do anything like tap measure or did you just do 50 drops.

50 drops after tapping hopper 20 times to settle powder but I "conditioned" the wiper first until it turned black with light pressure on the wing nut

As indicated by email from Calvin, I ran some W231/HP-38 through the Auto Drum with a new cone before conducting the 50 drop test. You can see that the elastomer wiper has blackened to be "conditioned".

Powder measure was reassembled with light pressure on the wing nut so there was no slop of cone. Hopper was filled with W231/HP-38 and lightly tapped 20 times to settle the powder. About 10 charges were dropped before starting 50 charge drops with target of 5.0 gr.

 

[Hooda Thunkit]

I have been using some version of the Lee Auto Drum measure for more than 35 years. From the Perfect Powder Measure to the Auto Drum to the latest Deluxe version of the PPM.

I have always gotten very good results, after closely reading the directions and following them.

I must say that sometimes the directions included in Lee equipment can be somewhat opaque, and I have occasionally resorted to calling Lee CS directly to ask for help/clarification. They have always been helpful.

After seeing your results, I'm not surprised at the repeatability of the throws. I doubt there are very many shooters, OCD notwithstanding, that can shoot the difference of 2/10 of a grain of powder in a handgun.

 

[Howa 9700]

If those findings were expressed in a traditional sense, which is 0.0 grains (tenths of grains, not hundreds), my guess is the vast majority of those drops would all be the same number? Bottom line is these Lee powder measures are good. Really good. I told that to one of the sales clerks at Graf's retail store a few months back......that the little Lee PPM might be the best powder measure they had......and he looked at me like I was nuts.

 

[Rebel Dave]

I have no complaints on my Lee PPMs, they all work excellent. I got rid of my Lyman, and RCBS measures. Now I only have Lee.

Dave

 

[SingleActionAndrew]

In my experience part of getting precision out of the auto drum includes not operating the ram so fast that you lose sight of the drum spinning. I can run the Dillon PMs much faster and still be accurate & precise, but going slow with the Lee mine measures N310 very well.

 

[LiveLife]

getting precision out of the auto drum includes not operating the ram so fast

During disassembly and reassembly of Auto Drum, I noticed cylinder hole of cone cycles past the bottom of hopper and moves past during case activated cycle whereas Deluxe PPM moves the cylinder hole right under the bottom of hopper for filling of powder.

I guess I could do fast vs slow filling of Auto Drum to see if cyclic rate has an impact on powder charge consistency.

 

[splattergun]

Calvin's note that they run better after putting a pound of powder through them is not wrong. That procedure helps the parts 'settle in' and, very importantly, coats the internal parts in graphite. That's when you'll see the best performance. I would add that consistency in your technique is also critical. Do everything exactly the same way every time, and your results will be more consistent. This is true for any powder measure.
I have no complaints about my PPM or LAD.

 

[Rebel Dave]

I run plain ole graphite powder thru mine once in awhile, seems to help.

Dave