RCBS Uniflow Powder Measure

[GW Staar]

Jesse: I got my conversion parts. They don't come polished and ready to use. I spent 10 minutes with mineral spriits to clean the anti-rust stuff off, buffed the parts and waxed them with plain paste wax. They, the small metering screw, the cylinder and the keeper/plunger thing. Go together smoothly now.

The design is interesting: you have to loosen the keeper housing a couple of turns before you can pull the spring-loaded keeper. Tightening it centers the keeper in a hole in the metering screw's sleeve and locks it. Yes I can see why you got impatient with it....not the most pleasant on fingers. There is a hole drilled in the keeper shaft that would allow you to run a wire through it and make a pull loop.....that would make it easier, but not necessarily more pleasant on the fingers. Thinking...

I have decided that I need at least one more measuring screw to test this thing.

The drum is drilled for the large metering screw, so the small metering screw is inside a sleeve....that's how they get one drum to work with 2 sizes of metering screws.

I have reservations on the small metering screw....the sleeve's end doesn't match the drum perfectly at the cavity opening.....so it'll catch a few small powder kernals between the cavity and the sleeve and the cylinder.

When I get the test going I will show pictures of that in the coming new thread.

 

[Paladin7]

I have the Uniflow Powder Measure with the Micrometer Adjustment, like you purchased, mounted on my Piggyback-4 Conversion to my Rock Chucker Supreme Press and all I can say is that it was one of the best investments I have made in reloading.

The Micrometer allows me to get repeatable settings and easy adjustment and it has been bulletproof for me.

You won't be sorry you made that purchase...

All the Best...

 

[higgite]

Jesse: I got my conversion parts. They don't come polished and ready to use. I spent 10 minutes with mineral spriits to clean the anti-rust stuff off, buffed the parts and waxed them with plain paste wax. They, the small metering screw, the cylinder and the keeper/plunger thing. Go together smoothly now.

The design is interesting: you have to loosen the keeper housing a couple of turns before you can pull the spring-loaded keeper. Tightening it centers the keeper in a hole in the metering screw's sleeve and locks it. Yes I can see why you got impatient with it....not the most pleasant on fingers. There is a hole drilled in the keeper shaft that would allow you to run a wire through it and make a pull loop.....that would make it easier, but not necessarily more pleasant on the fingers. Thinking...

I have decided that I need at least one more measuring screw to test this thing.

The drum is drilled for the large metering screw, so the small metering screw is inside a sleeve....that's how they get one drum to work with 2 sizes of metering screws.

I have reservations on the small metering screw....the sleeve's end doesn't match the drum perfectly at the cavity opening.....so it'll catch a few small powder kernals between the cavity and the sleeve and the cylinder.

When I get the test going I will show pictures of that in the coming new thread.

GW, do they not match nearly perfectly when the knurled keeper housing knob is tightened all the way? The reason I ask is that I just went and checked mine to see if it does as you described. I found that the contoured end of the sleeve can be either recessed into or protruding from the cylinder hole (depending on how hard you push the assembly into the cylinder) with the alignment pin seated but before the keeper knob is tightened down. But, once the keeper knob is tightened down, the end of the sleeve is almost perfectly smooth with the cylinder. I can feel the slightest lip in a couple of spots with my fingernail, but would be hard pressed to trap any powder at the end of the sleeve. Just FWIW.

 

[GW Staar]

No they don't. I am answering your post and any other post about the Quick Change on the "Uniflow conversion to Quick Change" thread so we don't highjack Mike's Mic'd Uniflow thread any longer.

There's nothing wrong with the Mic metering screw on a Uniflow.....it works VERY well. I have 3. I just want to see if RCBS's move away from it to the Quick Change is a good thing, or bad move by RCBS.

As everyone will eventually find out....the new RCBS Progressives come with the Quick Change P.M. minus the Mic metering screw. In fact the Mic will not work on the new Quick Change Uniflows!

Anyway talk about the Mic'd Uniflows here....the Quick Change on the new thread.

 

[mikemyers]

Don't worry about "hijacking" my thread. I find all these posts very useful.

You guys have already answered my real question - whether to go with the micrometer adjustment rather than the standard (old) version. From everything I read, the only difference is convenience - it's faster to return it to any given setting.

Now that I've switched my parts to the smaller ones, I'm getting excellent results as things are. It takes a few minutes to get it set for 5.2gr, but once it's there, it is very repeatable. In 50 rounds, all but 3 measured between 5.1 and 5.3, and the three that came to 5.4gr might be because I wasn't as consistent for those throws. It's necessary to do things exactly the same way each time.

I have no plans right now for getting the micrometer unit. Unless/until it becomes more accurate, it won't make a difference to me - I have lots of time.

 

[cfullgraf]

From everything I read, the only difference is convenience - it's faster to return it to any given setting.

Right, that and maybe a little easier to make adjustments is about all the micrometer gives you.

Now that I've switched my parts to the smaller ones, I'm getting excellent results as things are. It takes a few minutes to get it set for 5.2gr, but once it's there, it is very repeatable.

Good deal! Having the drum that is optimized for the powder charge thrown makes a difference.

It's necessary to do things exactly the same way each time.

This is important in operating any powder measure.

I have no plans right now for getting the micrometer unit. Unless/until it becomes more accurate, it won't make a difference to me - I have lots of time.

With a drum style powder measure like the Uniflow, I doubt the micrometer adjuster will ever improve the accuracy/consistency of the powder measure. It just makes the repeatability easier. With a little work and the right feel, the same results can be obtained with the standard metering unit.

Have fun with your new found skills!!

 

[mikemyers]

........With a drum style powder measure like the Uniflow, I doubt the micrometer adjuster will ever improve the accuracy/consistency of the powder measure. It just makes the repeatability easier. With a little work and the right feel, the same results can be obtained with the standard metering unit.......

Thank you - things are working very smoothly now. I'm curious though, about the way you wrote the above - are there other styles of powder measures? Is there something better now?

 

[cfullgraf]

The Dillon powder measures, the Lyman 55 powder measure, some of the Lee powder measures, Culver style powder measures (Harrell Precision and others), and some others are not drum style powder measures.

Each has its advantages and disadvantages. Except for the measures and dispensers made for the match and ultra accuracy crowd, most of the measures have similar performance and consistencies as the others, in my estimation.