Unburnt gunpower


October 24, 2011, 10:26 AM
Is this normal? The shot of the barrel is after the 6th shot, but I blew the powder out of the barrel after each shot. I didn't nothing to the cylinder and shots out of all 6 chambers.



Gun: Smith&Wesson Model 66 with a 6" barrel

Load: Powder: Universal Clays 3.5 grains
Bullet: Cast 158 grain round nose (from wheel weights)
Brass: Mixed headstamps
Primer: CCI small pistol
OAL: 1.5

Sorry for being a bit paranoid but, better safe than sorry.

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October 24, 2011, 11:02 AM
Yes, it is normal.
You are using a .38 Spl starting load of Universal and not getting enough pressure to burn it all.

If you are using .357 Mag brass, you are 1/2 grain under a starting load.

Up the powder charge and it will burn cleaner.


October 24, 2011, 11:14 AM
I wouldn't worry about it. Your load is not building higher pressures. Are you happy with the accuracy? With un-burned powder, the pressures will be inconsistent.
1. Load hotter, my book shows a spread from 3.2 to 4.6 grains for 158 lead in 357 brass.
2. Put a crimp on to hold and build a little more pressure. I don't like crimping.
3. Use mag primers.

I would opt for a little more powder to fully utilize it all. With 'wheel weight' cast lead, leading wouldn't be a problem.

If you are happy with the load, other than the leftovers, keep them from under the 'star' and enjoy.

Back in the dark ages I used 2400 and would have lots of left overs with no detrimental effects.


October 24, 2011, 11:20 AM
You also need to check and see exact what the granules left actually are.

Sometimes they are actually pieces of ash shaped like the powder kernels.

Gather a few and use a match to see if they even burn.

October 24, 2011, 11:40 AM
The brass is 38 special brass

October 24, 2011, 01:21 PM
That is awfully light to expect a medium speed powder to burn clean at. Try some Clays, or WST, or Solo 1000, or American Select, and the unburnt powder flakes will go away.

tightgroup tiger
October 24, 2011, 03:34 PM
At the shooting range I shoot at, before they are open and we are changing target holders, you can't even walk on the floor in front of the targets for all the unburnt powder.

It is like walking on #9 bird shot. That's from mostly factory ammo.

Are your loads producing a lot of smoke? That usually goes along with your loads not making enough pressure. When the burn rate of the powder is correct with the bullet weight, powder weight, and the barrel length they burn pretty clean. It's still no big deal.


October 24, 2011, 06:47 PM
I always get a few flakes of powder using Herco in 45acp. I also get my best groups with it, so it's a forgivable sin. :)

October 24, 2011, 07:02 PM
Universal takes a lot of heat/pressure to burn completely. I'm shooting it in .44 special and I'm at the top end of Hodgdon's data and still getting unburned powder.

For light .38/357 loads Clays burns much cleaner.

Just make sure you never confuse 'Universal Clays' with 'Clays'.

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