Strange powder weights with Unique

[Shooter6br]

I have a Hornady Pistol Meaasure.It uses brass bushings, i bought 4 lbs of Unique today. Using my measure i found all my measurements are 1 grain less than the Hornady chart. Example NO 16 bushing should drop 7.5 grains. It dropped 6.2 . All the weights are consistant. but a grain lower then listed. Using Universal the weighs dropped matched the chart exactly. i have not use Unique for at least 10 years. Is the chart based on the old formula Unique? Is it the powder is "dry" I am at a lost.:killingpc

[Heavy lead]

I find the same thing with Unique in the Lee powder discs.

[rtracy2001]

So far I have found that Unique DOES NOT meter. It will not drop consistently in any of my uniflow measures, Lee "perfect" powder measure, and those using disk and bushing type measures often complain aobut it not being consistent. (still waiting on my Auto disk Pro). If you can get consistent drops out of it, find the right bushing and relabel your chart

[ReloaderFred]

Don't use the chart for absolute powder weights, since they are just an average. You change bushings until you get what you need, or alter a bushing to drop the weight you need.

I don't use Unique at all, since I find it difficult to get consistant weights with any of my powder measures. I've got three Redding measures, two Hornady measures, a Belding & Mull measure and an old Hollywood measure. None of them like Unique or IMR 800X.

Hope this helps.

Fred

[Shooter6br]

I re- did my chart. I have to say that I get consistant weights. Did have some bridging with the use of thre Lyman mulit powder /expanding die. The trouble was with the "Universal adaptor. I removed ot and use case specific expanders . Oh well I have 4 lbs of Unique so i will carry on....

[Shooter6br]

Next buy will be Universal not Unigue

[Dan Cash]

Lyman 55 and Dillon measures give me fine uniformity with Unique. You guys who have all the trouble with Unique can just send it along to me and I will dispose of it for you.:)

[jimkim]

I read this on another forum. Get yourself a small aquarium aerator(one that vibrates) and rubber band it to the powder hopper.

[Judan_454]

I set powder measure a grain short of the charge weight I want, and trickle the rest.
Or you can tap the the powder hopper with pencil or a small wood dowel and you will more constant charge weights.

[mdi]

I have a similar prob. with my Hornady pistol powder measure. Nearly every powder weighed light when I was in southern CA. Moved to Oregon and my Unique measures heavier, and I get more variation. Same bottle of powder, same bushing in the same powder measure. But, it has rained 70% of the time we've been here. Humidity plays a large part in powders' measureability, or at least for me it does...;)

[old turtle]

Years ago I used Unique in my cast booit loads for 30-06 but switched to 2400 as it went through my old Lyman powder measure more evenly. I obtained some Unique recently and it seemed to meter much better than before. Perhaps they have changed the grains as I seem to remember them as a little more like flakes years ago. I know I am cheep as I still use to old Lyman 55 (I think) measure. In fact everything i have is old.

[NoDakJak]

I have so many problems measuring Unique that I have replaced it with PB in most of my loads. The burn rate is close to Unique but it is one of the finest measuring and cleanest burning powders that I have ever used. I still use Unique for some loads but I can load 100 cases with PB while I am farting around loading twenty with Unique. As the old advertisement goes: Trrrrrry it! You'll like it! Neil

[rbuck351]

I quit using unique for pistol because it won't throw consistant for me and went to W231 or Universal both of which throw very consistantly. I'll use up the unique for shot shells as a couple of tenths there doesn't bother me.

[biscot]

What's PB? (Aside from the stuff the Boolit is made of.)


I have so many problems measuring Unique that I have replaced it with PB in most of my loads. The burn rate is close to Unique but it is one of the finest measuring and cleanest burning powders that I have ever used. I still use Unique for some loads but I can load 100 cases with PB while I am farting around loading twenty with Unique. As the old advertisement goes: Trrrrrry it! You'll like it! Neil

[Char-Gar]

I don't know of any fixed powder dippers, bushings or chambers that throw the exact advertised charge weights spot on. Much depends on the technique of the user even if the volume happens to be correct.

Unique is a great powder and isn't the source of the problem here.

[mdi]

PB by IMR:


http://www.imrpowder.com/pb.html

[Kevin Rohrer]

I don't use Unique at all, since I find it difficult to get consistant weights with any of my powder measures. I've got ...a Belding & Mull measure... None of them like Unique or IMR 800X.
Fred

Interesting. I will need to check this on my B&M. Did you try cycling the handle a couple times for each throw to allow it to settle?

I will say that I have always used Unique in my Dillon 550b & 650 w/o a problem.

[Wayne Smith]

I'm loading Unique with an old Bair measure I got a couple of years ago. Uses brass bushings and drops consistently. Have no chart so I made one and keep it on my PDA. Have to add powders peridocally.

[Old Shooter]

I load handguns with Unique and usually use a RCBS Lil Dandy that I have had for 30 or so years. I check it every time I use it, starting out with the closest bushing to what I want. I find that it may vary 0.1 or so per session due to climate etc. but will be consistant each session.

[Doc Highwall]

Three variables that we have with powder is. 1, Burning speed from lot to lot. 2, Densities from lot to lot. 3, Moisture and what conditions the powder is stored in. This is why I buy larger lots of powder to lessen the effects of No's 1 and 2 because of changing lots, and No 3, I have control over as to how I store the powder.

[biscot]

Thanks for the clarification.
Might have to try it!


PB by IMR:


http://www.imrpowder.com/pb.html

[Kevin Rohrer]

To test the allegation that Unique does not meter well from a Belding & Mull powder measure, I filled my Vega Tools Schutzen B&M clone (pictured below) half full with Unique, set it for a typical .45ACP load of 6.2 grains, and ran three sets of tests using the measure and an RCBS 750 electronic scale. The drop tube is an original B&M micrometer tube.

Air temperature in my basement reloading room: 62.9F. Humidity: 42%.

Prior to the test I tapped the measure about ten times to settle the powder. In all the tests I made sure that all granules had exited the drop tube and lay centered in the pan:

Test-1: Cycling the measure one time per powder drop:
1. 6.2gr
2. 6.3
3. 6.1
4. 6.2
5. 6.2
6. 6.1
7. 6.1
8. 6.1
9. 6.0
10. 6.2
Average/Mean: 6.15gr
Mode: 6.1gr & 6.2gr
Range: 6.0-6.3gr
Median: 6.15gr
Variation: .3gr (-.2 to +.1)
Variation range: +-2.5%

Test-2: Cycling the measure twice per powder drop:
1. 6.1gr
2. 6.3
3. 6.5
4. 6.3
5. 6.2
6. 6.2
7. 6.2
8. 6.4
9. 6.3
10. 6.3
Average/Mean: 6.28gr
Mode: 6.2gr & 6.3gr
Range: 6.1-6.5gr
Median: 6.2gr
Variation: .4gr (-.1 to +.3)
Variation range: +-3%

Test-3: Tapped the measure vigorously five times between drops, then cycled the measure once per powder drop:
1. 6.2gr
2. 6.1
3. 6.0
4. 6.0
5. 6.1
6. 6.2
7. 6.2
8. 6.2
9. 6.1
10. 6.0
Average/Mean: 6.11gr
Mode: 6.2gr
Median: 6.1gr
Range: 6.0gr-6.2gr
Variation: .2gr (-.2 to +.0)
Variation range: +-1.5%

I apologize for not having any statistical software available. If anyone wants to take this data and figure SD, please do.

I'll let you draw your own conclusions from this, but I am satisfied that my B&M clone performs its function of accurately dolling out Unique, especially when using the third method in Test-3.

http://i666.photobucket.com/albums/vv29/KevinRohrer/Reloading/IMG_0407.jpg
The Vega Schutzen is the orange measure in back.

[Doc Highwall]

Who is the maker of the powder measure in the foreground and how do you like it?

[noylj]

Isn't it curious that Unique has been a VERY popular powder for handguns for 100+ years, and yet folks are rejecting it based on having problems metering it.
Sure "metered" OK in the '60s using scoops. Back then, powder was measured by volume and not so much by weight. Benchrest shooters didn't even know the charge weight, just what the powder measure setting or bushing was used.
If not near max load, just load it and shoot it and see how it performs. Even +/- 0.3gn will produce very accurate loads.
It meters nearly as well in my Hornady and Dillon powder measures as almost any other powder.
For me, one of the worst powders is TiteGroup. For me, it bridges and clumps in the powder measure and clings to everything (not static, it is actually tacky). Think they forgot to get rid of all the solvent in the batch I have.

[Kevin Rohrer]

Who is the maker of the powder measure in the foreground and how do you like it?

That is a Quick Measure, which is made by a one-man company in Washington state. I was having trouble metering stick powders on my Lyman 55 and was told to try this. I haven't had time to do anything with the measure beside set it on the stand. That piece of paper inside it is a packing slip.

I can best describe it as being a fixed version of the B&M. Instead of having a separate drop tube you use to measure powder like the B&M, the drop tube is fixed, but the principle is the same. It is supposed to be extremely accurate w/ all powders and unlike the B&M, very fast. I plan on reviewing it when I get a chance and will be using it this winter to load lots 30/06 using IMR4895.

Interestingly enough, this is the only piece of equipment that has a serial number on my bench that is filled w/ expensive loading equipment.

http://www.quick-measure.com/

[Old Shooter]

Have you guys tried a baffle in your measures ,and pre wiping with a drier sheet prior to starting (removes static) to use your powder measure?

[rtracy2001]

Have you guys tried a baffle in your measures ,and pre wiping with a drier sheet prior to starting (removes static) to use your powder measure?

Yup, no change, except maybe a fresher smelling powder measure.

[Skipper488]

Doc beat me to it, I've run into different densities from batch to batch of the same powder.

[OBIII]

I use a Lee Auto disk and my throws with Unique are always within 1/10 grain of what I am looking for.