Tuesday, June 5, 2012

More Powder Measure data

Well I tried some Unique powder today in my RCBS Uniflow

The grains are much larger than the Acura #5 and make it easier to handle and far less likely to spill.

It also gave better numbers

Count 70
Min 5.8
Average 5.966
Max 6.1
Stdev 0.0796
Within 99% 5.76< X <6.17
3 sigma 99.73% 5.73< X <6.20
Within 99.99% 5.66< X <6.28

The Max-Min divergence is much better, and the Stdev is better too.

I'm also running into resolution and accuracy issues with my scale. I've found I have to wait when the AC is on. A deflection means was selected in GBC.

When I get my own copy of the Lyman book I can check more centered in the safe range (4.8 to 6.2 grains). Here I was just running with 6.0 as my point of aim.

But I think with this powder I could have better results.

I'll need to test at the range of course.

One warning I did get was that Unique burns very dirty.

2 comments:

Mr.B said...

y'know, if yer gonna be right at the bleeding edge of max loads for .45 ACP, you might want to look at .45 Super cases. (http://en.wikipedia.org/wiki/.45_Super).Available at midway (http://www.midwayusa.com/product/941217776/starline-reloading-brass-45-super)

It is thicker brass, which should help the sort of failure you are trying to avoid.

As always, work up to the load.

The Jack said...

Bleeding edge? Lord no.

"When I get my own copy of the Lyman book I can check more centered in the safe range (4.8 to 6.2 grains). Here I was just running with 6.0 as my point of aim."

Unless I have a pressing need I'm going to /stick/ at the staring load.

Maybe work up by a couple tenths of a grain to ensure my sigmas fall within the safe zone.