mysterious white powder on my Ruger SBH

[James T Thomas]

Does anyone know what might be the white, chalky substance that appears at the juncture of my 4 5/8 barrel and top strap every time I fire my Ruger Super Blackhawk? -Blued.

The gun has been purchased new. I'm only firing factory ammunition in it.

The occurence seems to be heat related; when I fire three or full cylinders or more I notice a small deposit of the stuff. It will not wipe off with a solvent soaked cleaning patch. I scrape it off with a knife blade. It sort of chips off.

My guess is that it is a thread compound from the factory, and that the heat of firing causes expansion and it is extruded out onto the barrel top.

 

[Bullet Bob]

It sounds a lot like bluing salts that weren't completely cleaned off before the gun was assembled; although when I have seen that it's usually pale blue-green.

I believe if you'll call Ruger they'll pay for you to ship it to them, and repair the gun for you. It can then be mailed directly back to you.

 

[Old Fuff]

See if hot, soappy water will desolve it, and then dry and lightly oil the area. It is most likely blueing salts residue.