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macv
03-27-2010, 10:50 AM
HI, I just read an article on the 6BR sight about powder measures. It mentioned an older Redding powder measuer being tunned up. How does one do this. What can you do to it to make it more accurate than when it came from the factory. :confused:

abintx
03-27-2010, 11:16 AM
HI, I just read an article on the 6BR sight about powder measures. It mentioned an older Redding powder measuer being tunned up. How does one do this. What can you do to it to make it more accurate than when it came from the factory. :confused:

If you want to fine tune a RCBS Charge Master 1500 you call RCBS and ask for Don Legg Jr. their 1500 programming guru. If I was going to attempt tuning a Redding Powder measure, I'd call Redding and ask for one of their Tech Reps at 607-753-3331. It's been my experience, that there's nothing better then first starting with the one who designed and built the product. ;)

Larry Elliott
03-27-2010, 11:52 PM
About the only way I know of "tuning" a powder measure is by installing a baffle between the reservoir and the rotor. The factory baffles are something less than entirely effective, and a flat baffle with a 1/2" hole in the center of it is a little more effective. I've read that a flat baffle with an offset hole is better, but I haven't made any like that. That requires a lathe to cut the baffle without a center hole in it, but I haven't don't it yet. I think that a 1/2" hole is also too large. Maybe 3/8" and off center would be better.

Other than that I have no idea how a person would "tune up" anyone's powder measure, but my limited imagination has been pointed out by more than one person. :o

All this being said, measuring smokeless powder by volume, except for ball type powder that's very uniform and small in size like Ramshot TAC or X-Terminator, is like measuring firewood by volume (which I realize is the standard method of measuring firewood for sale - by cords, that is). The little sticks aren't all the same size, and don't all lie uniformly in order, so while the volume of the cavity in the measure remains the same, the weight can and does vary from throw to throw.

My various English teachers would scream if they had to read those last two sentences too. Life's hard isn't it? :D They're all either VERY much no longer with us or well over 100 years old, so.... :eek:

FBecigneul
03-28-2010, 08:55 AM
The method of stacking and measuring firewood depends on whether you are buying or selling. If you are buying you want it stacked in such a way that snow can't blow through the pile. If you are selling you want it so that the rabbit can run through it but the bassett can't.

What do you mean by "tune" a powder measure? Do you mean a tighter fit of drum to body with crisp edges or do you mean tuned so that two identical measures throw the same weight in any given click setting?

macv
03-28-2010, 10:53 AM
That's what I was trying to find out as well. In what way is one tunning a powder measure. Not that I have to have it throw the same amount always, because I always trickle the last 10th or so. I guess I have to search around more to find out excatly what is meant by that magic word "tunned". Maybe a call to Redding will get me a little more educated with the TERM as suggested. Until then, it will be just another question that I can store in my head. Thanks for the comments.

Don
03-28-2010, 05:14 PM
HI, I just read an article on the 6BR sight about powder measures. It mentioned an older Redding powder measuer being tunned up. How does one do this. What can you do to it to make it more accurate than when it came from the factory. :confused:


The tuning modifications that I have seen to the Redding powder measure that appear to have some merit, other than the baffle situation already mentioned are;

-spring loaded drum that maintains a consistant speed and flow rate and greatly reduces powder kernel cutting.

-velcro or like bump stops at the ends of the up and down strokes to prevent excessive and/or inconsistent banging of drum at the end of the throw.

-dry lubrication of the drum and metering thimble using dry graphite to maintain a smooth and consistent drum motion.

-polishing of the drum to body mating surfaces also to maintain a smooth and consistent drum rotation motion.

Don

Larry Elliott
03-28-2010, 06:11 PM
I AM getting old! Two other things I've done to both my Redding powder measures is to reverse the rotors so that they fill on the downstroke and dump on the upstroke, and lengthened the handles by about double. The first change prevents vibration from settling powder in the cavity in the rotor since it's not facing the powder reservoir which somewhat aids in more uniform charges. The second increases leverage so that if powder kernels are cut there's less force required by the operator which makes for smoother operation.

The first change is simple if you know how to remove the rotor from the measure body. The second only requires a length of 1/8"x1/2" steel strap that's bent to clear the measure body, reduced to about 3/8" wide (by filing!) on the rotor end to fit the slot in the rotor, and holes drilled for the screw that attaches the handle to the rotor and one for a knob or whatever on the other end. I found some ~1" OD black plastic knobs with #8 or 10 threaded inserts at the hardware store that work well.

Boyd Allen
03-28-2010, 06:31 PM
If you thoroughly clean and degrease the drum and mating body surfaces and buff a little tungsten disulphide into both surfaces with a clean patch, you will be amazed at how much the friction is reduced.

A few years go I read an article, on the internet, that was written by a fellow that made a study of powder measure modifications. He found that using a sturdier mount helped, reducing vibrations. Doubling the handle length was beneficial, and after testing numerous baffle designs, it turned out that a flat Plexiglas baffle with a half inch hole in the middle was the best design. He was working with a RCBS, but I see no reason why his work shouldn't apply to any measure. BTW, he threw thousands of charges, testing various mods.

paleduck
03-29-2010, 03:40 AM
It is great!





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oldguy
03-29-2010, 09:13 AM
I'm old but heck I just clean and use dry graphite to run through the unit a few times bang it's tuned.;)