Skans said:
Just buy an extra barrel, like a stainless storm-lake barrel, and polish it. Since it's already stainless, no problem with possible rusting. Note, stainless will show scratches as you shoot it some, but I suppose you can polish those out if it bother you.
Stainless steel is not rust proof -- but is more rust resistant than carbon steels. Tennifer (or similarly hardened) metals are also more rust resistant than untreated carbon steels.
The chemical components of the Tennifer process was changed for guns made in the U.S., as there were some environmental concerns during production. The name
Tennifer is a trademark owned by Glock, and while the formula was changed I think the replacement process might still be called Tennifer. In any event, it's still a similar process. From the Glock site:
Nitrite Treatment All GLOCK metal parts are treated with a Nitration finishing process that optimizes the molecular structure of those surfaces. This progressive technology delivers a high degree of surface hardness, maximum durability, and exceptional corrosion resistance, that provides many years of trouble-free service under the harshest environmental conditions.
Since nearly all ammo now available is non-corrosive, rust-resistant barrels aren't as important as once was the case -- as it was the powder (not environmental issues) that caused dangerous rust if the barrel wasn't cleaned regularly after use. Environmental issues (such as humidity, sweat) can still cause rust, but that sort of rust seldom affects semi-auto barrels.
If the owner wants a shiney barrel, he or she can probably polish the Glock barrel, as polishing off the darker finish won't remove the Tennifer treatment or the replacement Nitrited finish. The hardening processes used with all of these treatments (Melonite, Tennifer, etc.) changes the metal's surface but doesn't really have much to do with how it looks when you get the gun.
As suggested in the message cited above, buying an aftermarket barrel makes sense, particularly if you reload and want to use LEAD bullets (which is generally to be avoided with factory barrels).
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