Why is H-Universal so dirty?

[HardBall]

Guys,

I found my old load notebook from years ago and found that I had used lots of Hogdon's Universal in a M29 I once had. My notes (and memory) claimed it was EXTREMELY clean burning with mid-range charges behind a 240gr Lead SWC and (I think) with several different primers.

So, I bought a pound Friday and loaded some .357 rounds with it. 4.0 - 5.0 grains Universal behind 162gr SWC and 168gr Keith SWC using WSP primers. It was no cleaner than Bullseye, which isn't exactly "clean". There were also lots of unburned flakes in the empty cases, cylinders and barrel. I lay an old towel over my sandbags and remember Universal only leaving the mildest brown powder marks from the barrel/cylinder gap in My M29. This time, with both my M66-7 and BlackHawk, there were sooty black powder marks on the towel, with just as much powder residue on the cylinder flutes and top strap as when shooting Bullseye?

Why isn't it burning as cleanly in my .357s as it did in my old M29?

TIA,
Sean

 

[Mylhouse]

Maybe you weren't using a stiff enough charge?

 

[Mal H]

Agreed. 4 to 5 grains is near or below the acceptable minimum for Universal with that weight bullet in a .357 Mag.

Any powder is going to be dirty (incomplete combustion) when the max pressure attained is below a certain minimum.

 

[HardBall]

Guys on other forums are echoing your responses too. While Hogdon lists 4.0gr as a starting load for a 158gr SWC in .357 under their "Cowboy Action Load Data", I guess it's safe but not optimal. I'm going to load some rounds with 5.5 and 6.0 grains to see if it cleans up a bit.

I can understand a powder not burning as cleanly with too light charges, but I didn't expect such a drastic difference. Indeed, the one thing I remembered about Universal, while shooting mid-range loads in my M29, was the light brown marks left on my sand bag towel. Heck the reason I through a towel over my sand bags to this day is because of all the dark black soot deposited from all the other powders I had previously tried.

Thanks for the tips guys,

 

[Poodleshooter]

Try crimping harder as a substitute for increasing the charge if you must use Universal Clays. U-Clays is definitely a mid range powder. Load Clays or Titegroup if you want light recoiling loads.

 

[stans]

The more pressure a powder charge generates, the more completely it combusts. Your loads may not be generating sufficient pressure either through a charge weight that is just too small to generate the required pressure or the crimp is too light and the bullet pulls out of the shell before the powder can build to full pressure.

 

[Ala Dan]

Greetings All-

I use 4.9 grains of Hodgdon Universal under the Magnus 200
grain L-SWC bullet in .45ACP with excellent results. I've noted
Universal as burning very clean; virtually leaving NO residue.
Maybe the suggestion of a tighter crimp is the answer?

Best Wishes,
Ala Dan, N.R.A. Life Member

 

[HardBall]

Ala,

what primer are you using?

 

[Mark whiz]

I agree with the rest, Universal typically IS a clean burning powder. That .357Mag load is way too light. I use 7.0gr with 158gr LSWCs and that is a fairly light load. This powder also requires a pretty heavy crimp - as that will help keep the unburned powder grains to a minimum.

 

[HardBall]

Mark,

Hogdon lists 6.3gr as max with a 158gr jacketed bullet, 6.2gr as max with a 158gr lead bullet (the later load is under their "cowboy action data" and probably a bit conservative.

Whether or not 7.0gr is safe in your gun, I don't see how it would be considered "light" in anything but a heavy firearm- much heavier than my S&W M66

Thanks for the reply though,

Sean

 

[Ala Dan]

Greeting's All-

Hardball, I've been using W-W primers; but recently
switched over too Federal in both large and small pistol
primers. They seem a little softer, and offer a lot better
ignition.

Best Wishes,
Ala Dan, N.R.A. Life Member