NiB barrel extensions

[MWAG19919]

Just curious, why is a NiB BCG considered bad (or at least sub-optimal due to the way it wears), but a number of respected companies offer NiB barrel extensions? I've seen NiB BCGs fall out of favor and be replaced by NP3 (or good ol' fashioned phosphate), but only one company I know of offers a barrel with NP3 extension.

[okie]

I would guess corrosion resistance, but it doesn't do anything for the exposed bit of breach face on the barrel, which I don't think has chrome on it. Could be wrong about that, though.

Ease of cleaning in another selling point. Would also stand up to the chamber brushes with steel wire on the extension side.

In all honesty, though, there's nothing wrong with the standard extensions and coatings. These special coatings cause more problems than they solve. Nickel boron once it breaks in is actually not very slick at all, and the nickel teflon coatings tend to flak off. If I had to have some special coating, I would probably choose zirconium nitride, but I have yet to see anything that's as smooth as broken in phosphate. My Mk18 cycles smooth as glass and actually did from day one even before break in.

[DG23]

These special coatings cause more problems than they solve. Nickel boron once it breaks in is actually not very slick at all, and the nickel teflon coatings tend to flak off. If I had to have some special coating, I would probably choose zirconium nitride, but I have yet to see anything that's as smooth as broken in phosphate.

LOL!




If I go pull the oldest and most used / 'broken in' Colt Phosphate carrier I have and compare -

No way in hell it will be smoother than that finish.

[okie]

LOL!




If I go pull the oldest and most used / 'broken in' Colt Phosphate carrier I have and compare -

No way in hell it will be smoother than that finish.

Just wait until it gets worn down and starts sticking.

[DG23]

Just wait until it gets worn down and starts sticking.

Pretty clear to me you have zero experience running these things and even less than zero experience with modern finishes applied by reputable companies.

[okie]

Pretty clear to me you have zero experience running these things and even less than zero experience with modern finishes applied by reputable companies.

It's obvious from how shiny that bolt is you haven't used it long enough for those problems to start manifesting. You'll be singing a different tune.

[Todd.K]

What is wrong with your phosphate BCG and barrel extension than needs to be "fixed”?

The only thing I avoid if I can’t find phosphate is nitride. Nitride shouldn’t be used on parts with a critical case hardening process.

[markm]

Based on my NiB bolt breakage and the general sucky characteristics of the finish, I avoid it like the plague.

[JoshNC]

NiB wear characteristics suck. I would not choose to use it for anything.

[Disciple]

The only thing I avoid if I can’t find phosphate is nitride. Nitride shouldn’t be used on parts with a critical case hardening process.

In the AR which parts are those?