Green dot loads for plated .40 S&W?

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dgang

New member
Find myself with about 8# of Alliant green dot powder from trap shooting days. Since Alliant no longer recognizes Green Dot as a pistol powder I'm hoping somebody has some data for plated 155, 165, and 180gr. bullets in .40 S&W for use at the range. I have some idea from old Alliant manuals but they are for 150 gr. and 170gr. jacketed bullets, plus Alliant has changed their data for Bullseye and Red Dot, so I assume for G.D. also.They calling for more powder and quite a bit less velocity. Any help would be appreciated.
Thanks in advance.
 
U

Unclenick

Staff
CAUTION: The following post includes loading data not covered by currently published sources of tested data for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assumes any liability for any damage or injury resulting from the use of this information.

Lots of loads have changed since full graphical piezoelectric transducer pressure readings became available that reveal previously unidentified pressure issues.

In the case of Green Dot, if you look it up as a product and click on all the load recipes using it, you will find 44 Mag target loads, 45 Colt and 45 Auto. From that data and from QuickLOAD, it appears you can use Green Dot in quantities 10% lower than Bullseye. I would start 25% below a Bullseye recipe and work up while watching for pressure signs.
 
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dgang

New member
Thanks Unclenick, I saw the .44 and .45 loads on their site. I'm puzzled about reducing loads for Bullseye by 10 or 25%. Always thought Green Dot was a slower powder.
 
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dgang

New member
Sorry, didn't think about what you were saying. Reduce loads from the data for .44 and .45 loads. My bad.
 
D

dgang

New member
Unclenick said:
CAUTION: The following post includes loading data not covered by currently published sources of tested data for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assumes any liability for any damage or injury resulting from the use of this information.

Lots of loads have changed since full graphical piezoelectric transducer pressure readings became available that reveal previously unidentified pressure issues.

In the case of Green Dot, if you look it up as a product and click on all the load recipes using it, you will find 44 Mag target loads, 45 Colt and 45 Auto. From that data and from QuickLOAD, it appears you can use Green Dot in quantities 10% lower than Bullseye. I would start 25% below a Bullseye recipe and work up while watching for pressure signs.
Click to expand...
I understand with the newer methods of measuring pressure ( piezoelectric transducer) the powder producers (in this case Alliant) thought it safe to increase the powder charge and still maintain safe pressures. With Red Dot, Bullseye, and Green Dot the increase was across the board. However even with the increase of powder the muzzle velocity fell significantly, up to 200 fps or more. Is this a case of Alliant simply extrapolating from the pressure they had at the time or wishful thinking on their part? I have to think they had modern chronographs at their disposal.
 
U

Unclenick

Staff
DGang,

I meant reduce a 40 S&W Bullseye load when using Green Dot. The powder data in QuickLOAD is based on measured characteristics from samples of the powders and it gets higher peak pressures from Green Dot. Even though Green Dot's burn rate factor is a little slower than Bullseye's and its energy content is a little lower in QuickLOAD, Green Dot produces higher pressures in the software due to its characteristic burning curve having a sharper initial pressure climb than Bullseye's does.

Powder characteristics are complicated, and burn rate factor alone doesn't tell you all that is going on. Besides, what you see in Relative Burn Rate charts is not the order of the actual burn rate factors. The Relative Burn Rate charts put powders in their "behaves-as-if" order based on pressure developed by putting the same charge weight in the same cartridge with the same bullet and primer. It is frequently the case that the order of some pair of powders reverses if the cartridge or projectile or primer or change weight are changed. This is why different charts disagree about the order. The authors used different cartridges or bullets or charge weights or primers or any combination of all of those things.

The bottom line is the charts can help get you into the ballpark of what a powder is good for, but that's about their limit.
 
N

noylj

New member
Other option: unless you know how to work up loads for powders without load data, don't buy powders unless you have load data.
Plated bullets--use lead data.
Bayou L-RN, 155gn, Green Dot 4.0gn, 1.130" COL, start at 3.6gn and work up for safety.
This is lower than the starting load for Bullseye for this bullet.
 
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