I need some advice fellas,  I have a B/BC group that came with a upper I purchased at a gun show 3 weeks or so ago.  For the 1st 100 or so rounds the gun was really tacking, shooting nice dime to nickle sized groups.  Then the problems started.  It was not a fail to feed issue, it was that the BC was not cycling forward to pick up a new round.  I had to bang on the side of the gun and then you could hear the BC cycle forward and pick up the next round. Rinse and repeat.  I took the problem to the trouble shooting forum here and got lots of help and advice.  But while it seems to have solved the problem for the most part, the same problem crops up every 10-20 rounds or so.  Oh and did I mention that the key stakes sucked something fierce?

So now I have a B/BC that I dont completly trust. I am looking to replace the whole group.

But I have questions about the different finishes I have seen on them from different manufacturers.  I understand that the phosphate is the Mil-spec'd coating, and that is what I have on my Bushy M4gery, but the Chrome and Titainium coatings have me stumped.  Is it just a ease of cleaning thing, smoother operation?  Is it just about the "Bling" or is there some other reason for an exotic coating?  This is a range gun, tack driver, and sometimes small critter dispatcher, I wont be going into combat with it and my life wont depend on it (unless the parrie dogs attack).  If it will ease the cleaning and maintenace, what other drawbacks do they pose?

Any advice is welcome

It is easier to note areas that need special attention when cleaning.  I have a chorme carrier in my DPMS M4 and the whole chromed system (CROS) with my POF.  I have not complaints at all with them.

TS

I've found my ameetec chromed carriers are MUCH faster and easier to clean.  You can literally wipe the grime off and get back to better things.  I don't think reliability will be much of a factor, but i'd guess that a properly specd chromed carrier will have an edge their because of the increased lubricity of the chrome.  

I have heard chromed bolts are a no-no because they may be brittle?

I was looking at the DPMS chrome or the Titanium Nitride Plated Bolt Carrier & Bolt Assembly.

I have a second question.  What do I do if I buy a new B/BC and check the head space and find that I have a problem, what then?

Just pick up a CMT/Stag B/BC group from any of the dealers on the EE.  If you can find a new/like new complete Colt B/BC at a reasonable price that would be good as well.  Make sure you get a non-SP1 cut carrier (aka "enhanced" carrier or "shrouded" firing pin).

If you really want to get a premium unit, get a Leitner-Wise ACB and enhanced carrier ($).

Thanks Gamma, normally I would agree with going EE, and on some items I have in the past.  But I have a family member who is a FFL, so I get stuff at cost plus shipping.  Thats kinda why I was asking about the chrome and titainium coatings.  The LW B/BC are nice but I think they are a bit on the high price side, something to consider if your life is on the line, but overkill for a paper puncher.

Thanks for the comments guys.