[William R. Moore]

Decades ago, I bought a RCBS powder measure and had such a miserable time getting it properly adjusted that when I needed to change the setting, I bought another brand of measure.

I knew the problem was excessive clearance between the measures chamber and the adjustment spud. Having a wee bit of spare time last night and having determined that the measure's throw weight had drifted, I decided to fix the problem. Measuring the chamber bore and the spud, I found a 0.006-0.007 inch diameter difference. I had a 1/2 inch brass rod that was a real close fit in the chamber and first faced the end, then cut a slice off the rod on the lathe to maintain parallelism. This was centered and soldered into place on the adjustment spud. Son of a gun, end of problem.

I'm not planning on changing my use of this measure, but for those of you who may also have issues might want to consider this fix.

 

[Charlie Petty]

Sounds like a good plan.

I'm using one of the newer RCBS measures with the micrometer adjustment with no problems at all. I never did like their lock nut system because it was hard to make small adjustments.

 

[igli]

Congratulations, Bill... I was all impressed with myself for just putting Home Depot adjustment knobs on my Dillon powder measures, but you took the modification prize in a big way.

 

[William R. Moore]

I studied the thing a bit. If RCBS had held tighter tolerances it would have helped. The fit of the large capacity measuring chamber & spud was decent. I considered making a "top hat" to screw onto the metering spud to provide a way to measure lock-nut to reference point for adjustment, but the threads are wierd.

Spring loading the spud might have allowed not using a lock-nut.

 

[vaillancourthenry]

RCBS Powder Measure

Sounds like a good solution. As a side note, (and I`m assuming here that you`re refering to the Uni Flow powder measure). I`ve had one of these for 30 yrs. and long ago found that by using a dial caliper to measure the length of the adjustment stem I can return to a previous setting with scary regularity.