The New J& T barrels seem to be a Magnesium Phosphate finish as opposed to the usual Black oxide finish, same for the Cerro made uppers, am i  seeing right?
anybody else observrd this?

Thanks, s-3

Black Oxide is used, mainly, on stainless steels where Parkerizing won't work. Back oxide is a hot bath dip akin to blueing. Black Oxide has almost no rust prevention properties.Phosphating/Parkerizing is used for carbon steels. It is also a hot bath but the ingredients aren't nearly as corrosive as bluing/oxide salts. Aluminium is anodized, at least with the AR15.

ETA, you can't Parkerize alumium because the Al will dissolve. I've never tried to oxide Al.

Something I'm curious about, if they are not using phosphate then what is that match smell you get when you open and close a new gun?  Smells like matches when they first start up.  Are they phosphating the anondizing?

Our barrels are now Phosphated/Parkerized.  We switched when we started offering chrome lined barrels, no sense in having two different finishes.  Our uppers are hard coat anodized.

Jesse

Jesse, Thats what i thought, i just got my Expedition Kit in and the Barrel is Finished differently than my A-2 20 inch Kit i got in January, its definately a Parkerized Finish.

Tweak, if memory serves me right i believe there is a way to Parkerize Aluminum, i believe the Aluminum is coated with something else then it is Finished again. Might be wrong.

Quoted: if memory serves me right i believe there is a way to Parkerize Aluminum, i believe the Aluminum is coated with something else then it is Finished again. Might be wrong.

If the Al is coated with something else then you're not really Parkerizing the Al are you?

If there is a way to completely plate the Al with carbon steel then it may be possible to Parkerize an Al part.

I have seen a plated Al triggerguard from a bolt action (Weatherby?) rifle Parkerized. The gunsmith thought the part was steel bc of the plating. He bead blasted the part and dropped it in the Park tank. He came back to find a hollow shell. He hadn't fully removed the nickel plating during blasting and the Park solution ate into the Al through the voids in the plating created by blasting the part. The triggerguard was hollow when he removed it from the tank.

I would appreciate any documentation you could find on this process Spiffy3.

Maybe not the best thread to ask, but... any progress on your Tenifer-like process for barrels?

We're still not there yet, as usual things are taking much longer than expected.  We're still working on it though.

Jesse