Kahr Barrels - Stainless or Carbon

[Flieger]

I dislike the nickel plating on the Kahr barrels. I may be too picky, but a couple of boxes of ammo and the barrel looks like crap.
At least on the hood, any problem polishing or brushing the finish?

[jocko]

polish away,ur just taking off the dull sh!t finsih kahr puts on their nickel barrels. Once u get that barrel polished out, It willstAY THAT WAY . Adremeland some flitz does it in about 5 minutes..

[CJB]

Kahr has never said so officially, but my own investigation leads me to conclude that the nickle plating is an anti-galling feature, while also being a bit corrosion resistant.

One particular problem with stainless steel is galling, whereby the metal will adhere to its opposite part during operation. You'd see this on the top front of the barrel hood, and on the "bushing" contact areas of the barrel. Nickel plating is often used in industrial applications for its natural lubricity.

Not to contradict Jocko, but consider that when you polish nickle, you're removing some of it. And, the frosted surface will hold and retain lubricants to a greater degree than a highly polished one.

[jocko]

oh come on CJB, Ihave yet to see a nickel plated barrel worn to the bare stainless.Heh of alot more friction on in the metal to metal contact than any polishin. Once u get the dull finish off, ur not realy polisihin anymore, but merely cleaning off the powder burns etc.
U might be technically right but I just don't buy into that either..

Nickel is not a finish like choclate. It is extremely tuff, thats one reason they use it Just sayin. I guess if u rub any surface to clean it, ur basicaly taking off sumpin MAYBE.
I would hate to guess the hundreds of timesI have had my PMJ9 barrel off the gun and polished it back up with 600 grit paper where the ported slots will show powder burns. Still to this day shines like a diamond in a goats ass.

[CJB]

Just from shootin' my feed ramp is bare neked Jocko. Just sayin!

I should point out that the properties of nickel generally include low hardness, and high ductility. This accounts for its relative ease to polish with fine abrasives. This also accounts for its greater lubricity than steel-on-steel, and also its ability to prevent corrosion on underlying metals due to the generalized nature of soft metals to form impermiable layersin the plating process - meaning few pores.

Thats the basics of the metallurgy. You can polish nickel with compounds that would barely touch the stainless or carbon steels. The thick film nickel tends flake, so they try to hold its thickness to twenty microns or so - about .00075 inches. Thats 7.5/10,000ths of an inch.

Polish as much as you care to, just do so knowing what you're dealing with.

[gb6491]

I have a PM40 barrel that is non-stainless: I can darken a spot on the barrel hood with cold blue.
Regards,
Greg

[CJB]

Kahr says the barrel is proprietary steel. That could be anything. The 3 inch diameter claim, is prior to hammer forging.... which just by the way, offers no particular price advantage to polygonal or conventionally rifled patterns. It might be said by some that the polygonal mandrel is actually more expensive to produce than a conventionally patterned mandrel, but I'm not (yet) sure of the production life of a mandrel. Its quite high though, in the order of many thousands of barrels, not hundreds or a few thousand. The economy of production would therefore give a slight advantage to the conventionally patterned barrel... but that advantage would be oh so slight. Marketing folks though... would be first to say "the more expensive to produce polygonal rifled barrel", even if the production cost difference was literally less than a nickle.

[b4uqzme]

Polish away flieger. I've been able to get the barrel looking good again with mag wheel polish and some gentle rubbing by hand. Doesn't look like I am in any danger of rubbing through the nickel yet.