I use Unique to reload 9mm, .357 magnum, and .44 magnum. I can have +/- .4 grains of powder for the magnum loadings. Since I load midrange of data and am not a bullseye shooter this really does not bother me. I am curious what others get and put up with. I use a Lee Classic Turret press and am very happy with it.
The only Unique loads I use, that don't have powder charges thrown by hand, are those that are done on my progressive press. In that case, my tolerance is +0.2 gr / -0.1 gr. However, the Dillon powder measures drop Unique with such accuracy, that it usually deviates less than 0.1 gr. And, the Unique loads that I run on the Dillon were specifically developed with that tolerance in mind. As far as "Magnum" loads and Unique, though... I don't mix the two. The burn rate and density of Unique just doesn't get along well with the 'magnum' loads. I'm a big fan of Unique. I use it in quite a few cartridges and loads. But... Unique in 'magnum' cartridges is like putting a 2.0 Liter supercharged 4 cylinder engine in a semi-tractor. It might put out enough power to get the job done, but it is far from ideal. ...not to mention, Unique is a dirty powder, unless you're running it at near-maximum pressures. In 'magnum' loads, that rarely happens; so it's always dirty. Most of my "Magnum" loads are in .44 Rem Mag, .32 H&R, and .327 Federal. In those cartridges, H110/W296, H/IMR 4227, 2400, Pro300MP, Lil' Gun, True Blue, and Blue Dot do the dirty work. Out of my Uniflow powder measure, my general tolerance is +/-0.1 gr. Some loads may have been developed specifically to allow for more deviation; but I'm usually pretty anal about being exact.
I understand that Unique is not the best powder for magnum loads. However I found that 9.5 grains of Unique with a 200 grain GD bullet is very manageable with my S&W 329PD. It shoots about like the Buffalo Bore Heavy 185 grain .44 Special ammunition I bought a few years ago and use when I carry the 329PD. It makes good practice ammunition for my 329PD, and yes it is dirty ... but, I clean my guns after each range session. You use a lot of powders. I only use two, Unique and 2400. I keep it simple, as I have yet to confuse the two. I do not even get +/- .01 with the 2400. It seems I get a variance simply by how much force I use on the Ram Lever. It seems it does not take much deviation to get a measurable variance. A bummer about the spammers on your web page. Looking at your reload bench the first thing that caught my eye was how 'Hungus' your bench was ... two layers of 3/4" ply wood. It looks like the bench is stout enough to climb under in the event of an earthquake. Nice work.
I completely understand the desire to use as few powders as possible. I often wish I didn't have so many powders to choose from. But, I have an addiction... I'm always chasing that perfect load. I'm not really after velocity, like many reloaders in my position; but accuracy and efficiency. And, sometimes, I come across powders that are just terrible performers in 95% of loads (True Blue), powders that are dangerously unpredictable in many loads (Blue Dot), or powders that just don't like my firearms (Varget and Hunter); all mixed in with powders that are fantastic all-around performers with minor limitations (Unique, HP-38/W231, Bullseye, etc). But... every one of the 'bad' powders has found a place on my powder shelf, because I found something they excel at. It might be highly compressed loads in a particular load (Blue Dot in .44 shot shells), specialty high pressure loads in small pistol cartridges (True Blue in .32 S&W), or extreme accuracy loads intended only to be fired in sub-freezing conditions (Hunter in a .270 Win Elk load). Even if I end up regretting the purchase of a particular powder, I feel like I have to use it. So, I keep searching until I run out, or find the load. I wasn't trying to get off topic with that. I was hoping a little more detail would shine some more light on why my powder charge tolerance is what it is. For me, "good enough" usually isn't good enough. I almost always need a little more.
I forgot to thank you for your comments earlier. Yea, the spam is a pain, but most visitors have other ways of contacting me. It's unfortunate that no real discussions can take place, though. As for the bench... it's a tank. The finished product should be around 220 lbs just for the base of the primary bench. The whole thing (shelves, light bar, both benches, etc) should weigh in around 400 lbs, empty. I like stable work surfaces. As for its size... I like to have room to get the job done. Plus, the right bench (without shelves) will double as a gun cleaning station. So the extra space will be used.
whan I load the hopper with Unique,I give ti several light knuckle raps,dump several dumps,then a few more raps.Makes the drops much more consitant.
I weigh each powder charge no matter what I am loading be it 9mm or 30-06 I would estimate my variation is less then .1gr across the 6 pistol calibers and 7 rifle calibers I load for. Been doing it this way since I was 11 year old about 44-45 years ago. Never damaged a firearm or a person with a handload not going to change. I generally work with 8 different pistol powders and 9 different rifle powders. Some measure very well from the powder measure (like H110) some do not like IMR 3031
For pistol cartridges my tolerance is +/- .1grs for OAL my tolerance is +/- .003" primer seating depth is .002-.005" below cartridge base. I generally hold my tolerances to around 3%, so for rifle, dropping a 50gr charge the tolerance is +/- 1.5gr which most extruded rifle powders will easily hold to, it's better for ball powders. Dimensional checks on the cartridge are performed with a gauge or optical comparator.
AMP - considering your background I'm guessing you have loaded more than everyone else here combined...
