Unique metering problem

[djml66]

I wonder if I am doing something wrong...

I use mostly Unique, and an RCBS dispenser and I have noticed (when I measure every sample)that I get a fairly consistent variation of +/- .2 grains. This is the only powder that I have tried to use in this dispenser and I have a good stock of it! I have read descriptions of the proper hand movement, double-tapping etc. and can't seem to get any improvement.

Looking for suggestions.

 

[djml66]

Although it's probably obvious, I might add that I am a reloading newby. Just been reloading a little over a year, and about 3k-4k total. So stating the obvious won't hurt my feelings.

I reload mostly 45acp and the usual charge is either 8 grains (185) or 6 grains (230).

I am considering trying some Power Pistol, which seems to have smaller granules.

 

[Ron H.]

Sir, Unique does not meter well. In addition to the variance you've noted, sometimes Unique will "bridge" in the measure, and you won't get any powder at all. (Been there, done that. The bullet stops in the forcing cone, tying up the gun.) Ball powders meter much better and thus are better suited to loading in volume, as on a progressive press.

FWIW, I like Unique and use a fair bit of it, but I weigh each charge instead of trying to run it through a powder measure. This works fine for what little loading I do, but it gets tiresome if you're doing more than 50 or 100 rounds at a time. Were I loading in volume for pistol matches or something, I'd use a different powder. For .45 ACP, you'd probably be better served by 231.

Hope this helps, and Semper Fi.

Ron H.

 

[Kevin G]

I use the RCBS Uniflow and initially had the same problem you have now w/Unique.
Don't know if you've done these already, put a baffle in the powder hopper and switch to a small (pistol) rotor. I found a big improvement, still using Unique.
Good Luck, Kevin

 

[fredj338]

Originally posted by Kevin G:
I use the RCBS Uniflow and initially had the same problem you have now w/Unique.
Don't know if you've done these already, put a baffle in the powder hopper and switch to a small (pistol) rotor. I found a big improvement, still using Unique.
Good Luck, Kevin

That will certainly help. Technique is really important though. With my Uniflo, I tap up & down. THis seems to give me charges that vary no more than 0.1gr w/ the small rotor. You'll need to throw 5-6 charges to get things settled in & anytime you stop, thro the same 5-6 charges back in.

 

[fredj338]

I have no problem getting within +/- 0.1gr w/ Unique in my Dillon or the Uniflo. Technique is most of it in the Uniflo. In the Dillon, make sure the pwoder return rod is snug & polishing the inside metal of the hopper helps.

 

[Erich]

Unique is a PITA to meter, as others have observed. I either weigh every charge for precision or else I load lower and don't sweat the variance when using it. And, I've been using different powders instead of Unique a lot more lately . . .

 

[WR Moore]

If you get 0.2 gr variation with ANY powder out of an RCBS measure, you're a magician! For general reloading purposes, that variation isn't worth worrying about. If you're bound and determined to ride the maximum charge line, by all means weigh every charge.

I use quite a lot of Unique and have found that measures like the obsolete Hornaday Pacific bushing measure to be consistant in charge weight. Just don't bet on the bushing producing the charges the charts claim, but that's with any powder.

Ball powders are more consistant in their measuring, but require tight tolerances in the measures. The measure on my Dillon hasn't needed adjustment since initial setting in....back in the last century.

 

[djml66]

Hmmmmm. Well, I will order the baffle and the small rotor. I found them on MidwayUSA, and they are in my cart. If I can't improve on what I am getting, it's going to take a long time to use up about 14 lbs of Unique measuring every charge! But I'll check Gander's to see if they have any 231, and also try some Power Pistol, which I have some of.

 

[MKT]

I found that operating the handle briskly, read: making a very audible "clack" at both ends (up and down) makes for more consistent throws. I suspect the force of the movement shears the powder grains quickly. Only downside is you have to keep close eye on the lock ring as it will loosen under repeated hard knocks.

 

[Skip Sackett]

What does it matter? I'm being a bit silly but does it show up in accuracy? What about in your chronograph data? It may not matter. As long as the high and the low is safe there may be no perceptible difference in the loads, MAYBE.


There may be and that is a cause for concern. If not, just keep an eye on it and go from there.

Volume and weight are two very different things. It is possible to have one or two big flakes in a throw or a bunch of small ones. Either on will affect weight, the volume will stay the same.

Unique is a pain to meter, but many do it. I'm not one of them, never got the Unique bug. With the size of the charges that you are throwing there shouldn't be that kind of swing though. I don't know much about the Uniflow as I have never had one. Poorly metering powders do better when the throws are bigger.

Just a question though. Can you put the bigger rotor in and get what you want with it fully adjusted to it's smallest volume?

Just a thought too. Ammunition manufacturers don't weigh each charge, they use the volume method too.

FWIW

 

[canoe on the yukon]

I only weigh charges that are near max when I load for pistols.For anything well within safety range,volume measuring is fine.If it really bothers you,ball powders will be your best bet as they meter better than anything(which is why they were developed).

Having said that,I use Unique more than any other powder for pistol loads and normally by volume.A couple of tenth's of a grain would be hard for me to notice on target.

 

[Win]

When I shoot 600 yds in high power (.308 or .223) then I weigh cases, weigh bullets, weigh powder charges, measure case neck diameters, etc. Anything less than 600 yds, the problem is usually me...not the gun or the ammo....(when the ammo is assembled with 'reasonable' care). With 45 acp at less than 25 yards, I don't think .2 grain variance will give you too much grief...especially with mixed brass, etc.

 

[gregintenn]

I have a Lee powder measure. I have found that it meters stick powder pretty accurately, ball powder with amazing presicion, and flake powders, such as Unique, not well at all. I measure and adjust every charge with all types of powder. It is slower, but I have consistant ammunition.

 

[djml66]

If it was an extreme variance of .2 grains, I wouldn't give it another thought. But within a half-dozen throws I am seeing plus and minus .2. Occasionally I have seen as much as .4 over. I don't know what the low end is--I can usually tell by looking in the case if it's much under, and I just toss it back in the tube. If I were loading 20 grains, it wouldn't matter, but I like to load to around 875 fps for a 230. For me this works out to 6 grains of Unique. 6.4 would be somewhere around 950 or more, and while I don't think the occasional flyer would hurt any of my guns, it bothers me. And you're right that it doesn't do much to hurt accuracy (my guns and ammo are more accurate than I am).

I am a retired engineer and can't turn off the urge to control my environment just yet. I do "get silly" with plinking loads using 185 Berry HBRN with light charges (about 7.5gr), and disregard the variation. I know the velocity is all over the map, but the tin can doesn't care. And most of my favorite 45's handle the low end without jamming.

I have a different attitude about the 230 JHP, though.

Hopefully, the small rotor will bring the distribution within something I can be happy with.

I appreciation all the help!

 

[Skip Sackett]

I am a retired engineer

NOW I UNDERSTAND!

You aren't wrong, and I hate this saying but, for your handgun loads, +/- .2gr on a target type load is "close enough".

Sorry, I know that saying just sent you into spasms!

 

[gregintenn]

It seems to me that a .2 grain variation in, say, a 3 grain load would be a pretty good shift percentage wise. A 4 grain variation in a 60 grain rifle load would be totally unacceptable to most anyone, while it is the same, percentage wise. I might just have a bit of engineering cobwebs in my brain as well.

 

[djml66]

Maybe it's the engineer in me, but I get perhaps as much pleasure re-loading as shooting. And that's a good thing cuz I spend a whole lot more time doing the former than the latter. Someday I might be ready for a Dillon, but not anytime soon--I have to be able to look in the case before the bullet goes in. So for now, a fancy setup is an RCBS turret press.

 

[fredj338]

Originally posted by smith crazy:

I am a retired engineer

NOW I UNDERSTAND!

You aren't wrong, and I hate this saying but, for your handgun loads, +/- .2gr on a target type load is "close enough".

Sorry, I know that saying just sent you into spasms!

With Unique, probably true, but w/ some pwoders, that much variation can be very bad if you are already running high end loads w/ uberfast powders.

 

[Ridgway]

FWIW,I've found the lighter charges of Unique to be tough to throw, but have had really good luck from about 5 grains and up using the ancient Lyman #55 measure. Something about being able to adjust the shape of the cavity plus using the knocker seem to work with Unique. Not sure if its worth going out and buying a new measure or not, your call there. One of Hogdon's powders, Universal Clays I believe, is supposed to be a great substitute for Unique and much easier to meter, but I have no real experience with it. I'm sure others here could tell you more than me.

IIRC, the last loads thrown with my Lyman #55 were 7.3 grs Unique for the .357 Magnum. I checked each one of the first twenty or so charges thrown and none varied more than a tenth.

Regards,
Ridge