Powder measure problem with RCBS turret press

Longshot Lil · July 17, 2012, 02:00:18 PM

Hi all.

Hubby and I have a bit of a quirk with our uniflow powder measure on our RCBS turret press. It's about as tight as it can be, but the measure adjustment knob keeps loosening up while we're using the press! It's really frustrating to have to keep tightening it up again, especially since there isn't a wrench we can find that will fit on the nut without scratching the powder coating on the powder measure (the wrench rubs right up against the measure). Does anyone else have this problem and if so, have you found a solution to it?

Many thanks,
Lil

Four Eyes Henry · July 17, 2012, 04:49:19 PM

Hello there,

Are you missing the "bow washer" to lock the thing?
See http://www.rcbs.com/downloads/Parts_Book.pdf page 17 18 there is the uniflow and part nr. 09260 is the washer.
I am using the uniflow for years now and never had that problem. Could it be that the measuring screw is touching the housing because of very small charges and works itself loose?

Hope this helps

Fairshake · July 18, 2012, 10:29:11 AM

The large nut on a Uniflow is the bushing nut and it holds the measuring stem in the drum. It should be tight by using a regular adjustable wrench or socket of the correct size. This has nothing to do with the powder adjustment as the stem should also have a round nut with knurled surface which is by design made tight with finger power only. If this nut is not present then the adjustment stem will turn freely regardless of how tight the bushing nut that is against the drum is.
The better set up is to purchase the micrometer stem which will give you an easier adjustment and a quicker return to previous settings. The standard set up is shown on page 17 and I don't know why it was changed to 18. In the download on page 18 is the micrometer setting which is a option and not standard issue which is shown on page 17.
Later Fairshake
By the way I have 3 RCBS measures that I have used since the 70's.

Four Eyes Henry · July 18, 2012, 11:36:52 AM

In my PDF reader it came up on page 18.
But you know what I mean, right

Longshot Lil · July 18, 2012, 08:29:42 PM

It came up page 18 on my pdf reader too

We'll have to take it apart and see if that washer is missing. I have no idea since hubby put it together and that was months ago and he doesn't remember either. Thanks for the tip, will let you know what we find out.

Lil

Pappy Myles · July 19, 2012, 09:22:24 AM

May I suggest the use of the UPM Micrometer adjustment screw. I have one on my progressice and all I have to do is record the tetting.

I have an old lyman Spar T 6 station turret press, that I have a little Dandy with a couple of rotors for my favorite charges. Its a no brainer here, change the charge by changing the rotor. no adjustments necessary

rickk · July 19, 2012, 11:38:59 AM

Lil, If yours is the same ans mine, the locknut is a knurled round nut that does not need a wrench at all. I usually snug it up just a bit past finger tight with a pair of pliers and it stays put.

The nut that would take a wrench, like Fairshake says, holds the measuring stem in place and is not part of the adjustment. I don't recall ever having a problem with mine loosening up.

Longshot Lil · July 19, 2012, 01:34:38 PM

It's the black nut that uses a hexagonal wrench (like an adjustable or crescent wrench, I believe part number 09014, called out as number 8 in the drawing) that is coming loose, and hence the knurled adjustment knob is loose as well. They end up moving as one unit, and as soon as the hex nut loosens, the knurled knob moves with it, loosening and making a bigger throw of powder. At this point, we are always throwing the same powder weight, since we are loading only one type of shell. I'm going to be going down to the basement to take that apart and see if that washer is in there. It's annoying to have to do this though, because we have the measure set PERFECTLY.

Longshot Lil · July 19, 2012, 02:33:55 PM

Ok, I just went down to look at our measure, and before I did, I pulled the booklet that came with it. The assembly diagram as well as the parts list does NOT have any kind of washer. There is NO part number 13 (09620) in the diagram or in the parts list.

It is the measuring cylinder bushing that keeps coming loose (number 7 on my diagram as well as the one linked to above). The knurled screw lock ring is snugged right up to this (tightly) and it's the whole assembly that is coming loose. The cylinder bushing is what comes loose, the knurled screw lock ring and the crowned measuring screw come along for the ride, but they are staying tight with the cylinder bushing. It's the whole unit that comes loose. Once I tighten that back down, the measure is perfect again, but it shouldn't be coming loose like that.

I am going to give RCBS a jingle and see what they have to say about this.

rickk · July 19, 2012, 02:54:26 PM

If all else fails, there is always a drop of Loctite.

Make sure you use the blue stuff (242), not any of the red ones (like 271) or Green (290).

Blue Loctite (242) is made to come apart easily with normal hand tools.

Red and green want heat and big wrenches or an impact wrench along with many expressive words to come apart.

Only put it on the big bushing, not the adjustment stem. A single drop on the treads is all you should need.

Rick

Longshot Lil · July 19, 2012, 03:02:15 PM

I just spoke to RCBS customer service. It IS supposed to have the bow washer between the lock ring and the cylinder bushing. Apparently ours was one that was "pre washer" (even though we've only had it for about 6 months).

RCBS is sending out a washer, along with a new lock ring and cylinder bushing at no charge. Hopefully this will take care of the problem.

I asked about the micrometer adjustment screw. That really is only necessary if you're throwing a lot of different loads for different calibers, which we are not. We're doing one load only, so being able to readjust quickly is not an issue for us. It gets set up where we want it and left there. Thanks for that suggestion though.

Should have the new parts by the end of next week or so and we'll see what happens. Have lots of loading to do for CAS, so it should get a fair test. Will try to remember to post the results once we've tested out the new parts. Thanks for all the help y'all!

rickk · July 19, 2012, 07:27:09 PM

I'm confused...

On mine the thing that would take a socket wrench is the bushing (part 7), and the knurled thing that might benefit from a bow washer is the lock ring (part

.

If it is part number 7 that is coming loose, I am not sure how a bow washer (part 13) is going to fix that.

I just went and looked at mine... it is "older than dirt" and does not have the bow washer. I can see where a washer under the lock ring would be good, as I have had the lock ring loosen.

As far as the bushing (the thing with the hex nut as part of it) does, it is just screwed in place and it doesn't move. I tried hand loosening it anyway and it is in there but good. I know I have had it apart before, but it didn't seem to be an issue to put it together again and stay together. My measure is half full of powder or I would have taken the bushing out just to have a look-see.

I'm curious as to how this all works out.

Rick

Longshot Lil · July 20, 2012, 08:11:52 AM

RCBS is sending me the bow washer not to fix the problem with it unscrewing, but because they feel it should be in there for easier use, etc.

They are sending me a new bushing and knurled lock ring to try to correct the problem. Great that yours is staying together and not loosening, but ours is not and it's very frustrating to have to keep checking it or find that we have to re-throw some of our loads because it loosened and the charge is way too high. They are trying to fix the problem for us by sending us new parts that seem to be causing the problem. There could be a defect in the bushing that isn't letting it stay in.

rickk · July 20, 2012, 09:01:44 AM

OK... that makes sense now.

I will have to get myself one of those washers as well. I always snug the knurled locknut with pliers to make sure it doesn't loosen. The washer seems like it would fix that problem.

Thanks,

Rick

Four Eyes Henry · July 20, 2012, 03:21:02 PM

Hope it will be solved now

I misunderstood the problem a little, never had the whole thing coming loose

but something good comes out of this, rickk is getting a bow washer now

no more pliers.

Longshot Lil · July 20, 2012, 03:51:27 PM

Quote from: rickk on July 20, 2012, 09:01:44 AM
OK... that makes sense now.

I will have to get myself one of those washers as well. I always snug the knurled locknut with pliers to make sure it doesn't loosen. The washer seems like it would fix that problem.

Thanks,

Rick

That's what I'm told it's supposed to take care of.

Longshot Lil · July 20, 2012, 03:53:46 PM

Quote from: Four Eyes Henry on July 20, 2012, 03:21:02 PM
Hope it will be solved now
I misunderstood the problem a little, never had the whole thing coming loose but something good comes out of this, rickk is getting a bow washer now no more pliers.

Yep, it's the whole contraption coming lose. Kinda hard to get accurate measurements if it's coming loose like that! I hope this will fix the problem too, and I'll report back after we've installed the new parts and given it a go.

Thanks to everyone who has tried to help with this, hopefully someone else will be able to correct a problem from this post.

Lil

Longshot Lil · August 08, 2012, 10:26:42 AM

Well, we got the new parts, and oddly the last two times we've reloaded, the nut hasn't come loose. I guess we reefed it just enough to make it stay put. Now I'm afraid to take it apart to install the new parts. It's measuring nicely right now! Go figure. I'm of a "if it ain't broke" kind of mindset right now, especially since we're doing reloading on a regular basis. Maybe when winter hits and we're not shooting as much, I'll take it apart then. WIll try to remember to report back here. Thanks all!