[BFPGW]

I thought I read PJ and a few others describe their experience as being what I found yesterday but I can't find the thread in a search so.......

Been trying out my Lee Pro Auto Disk on 45LC rounds for the first time while house-bound with a sinus infection. I have used 15.4 grains of 2400 under 250SJHP and later under 250gr LFN cast (per recommendations from several of my fellow members) but I weighed and trickled each charge back then.

I found the 1.18 disk was supposed to throw about 15.7 or thereabouts. It actually threw charges in the low to mid 14.x range. I moved up to the 1.26 disk and it gave me 15.6 to 15.8 charges which is fine for me.

Seems like PJ or somebody has found that frequently the Pro Auto Disk will need to use one disk orifice larger than stated in the guide. For me, that isn't the case with small charges like 6.x of Unique for the 45LC, but the larger volume needed for 2400 seems to require a larger hole.

Does that sound right or am I delirious from medication?

 

[Charlie98]

Different types of powders will meter differently. Heck, I have calibrations written down (for, example, 6.5grn Unique = 5.75 in the small cavity) for my Hornady powder dump and I still check them every time I reset the chamber... for good reason. In much the same way my bushing in my MEC shotshell reloader will throw lighter or heavier charges of WST... depending on what kind of mood it's in.

 

[papajohn]

It has been my experience that when using the disk measures from Lee, their chart often (like almost always) shows a heavier charge than what is actually thrown. Powder can vary in weight and density, they lowball the figures to keep you from getting more than you bargained for.

With the flake-type powders I use a lot, I usually figured that what I got was about 8% less than what they said it would be, and the scales generally backed that up. Weighing ten charges and finding the average will give you a solid figure to work with. I made up my own charts, to keep track of what was actually thrown, but I modified them every time I changed lots of powder. Some were the same or nearly so, and some most definitely were NOT.

 

[BFPGW]

Thanks PJ, I thought that was your experience too. I've made notes on my load cards as to date, actual weighed charge, and which disk used that time. That should keep me on track. I usually load up 50 then weigh every cartridge in one column on my Frankford loading trays.

 

[BlueMike]

I also have the same experience with the Lee disc throwing smaller charges...especially with flake powders like Unique. Like others have said, I made my own chart and they will most always throw within 0.1 grain of my chart. I tend to quickly weigh about every 5th charge to just make sure when using the flake powders.