"Best" BCG

[Jupguy]

I totally agree.

[dont_tread_on_me]

Historically I’ve used BCM because after ‘04 that’s what they built their rep on and was born out by Pat and others. It seems like that angle has been taken over by SOLGW these days and I think it’s interesting that they haven’t come up in this thread. That being said, I sprung for the Geissele REBCG and we’ll see how the NANO does on it. I believe SOLGW is saying these coatings promote wear as they don’t absorb lube like phosphate does but I’ve yet to test that personally.

[Cane55]

Historically I’ve used BCM because after ‘04 that’s what they built their rep on and was born out by Pat and others. It seems like that angle has been taken over by SOLGW these days and I think it’s interesting that they haven’t come up in this thread. That being said, I sprung for the Geissele REBCG and we’ll see how the NANO does on it. I believe SOLGW is saying these coatings promote wear as they don’t absorb lube like phosphate does but I’ve yet to test that personally.

Eugene Stoners original BCG’s (on the AR10’s & AR15’s) were both chrome plated. The AR15 only switched to phosphate because Colt didn’t want to spend the extra money or time chrome plating them at the time. Decades later when Stoner was working for Knights and developed the SR25, guess what, he made the entire BCG all chrome plated. Nothing wrong with phosphate though, it’s proved itself for decades.

[lysander]

Eugene Stoners original BCG’s (on the AR10’s & AR15’s) were both chrome plated. The AR15 only switched to phosphate because Colt didn’t want to spend the extra money or time chrome plating them at the time. Decades later when Stoner was working for Knights and developed the SR25, guess what, he made the entire BCG all chrome plated. Nothing wrong with phosphate though, it’s proved itself for decades.

Not, quite.

The original bolts and carriers were "Electrolized" not hard chrome plated. Different process, slightly different (and better) qualities, both look the same.

In the 1960s, only one place "Electrolized" parts, as it was a patented process, and it was it Los Angeles. Having parts Electrolized in central Los Angeles 10 miles away is no big deal if your manufacturing facility is in Hollywood. It quite a different thing if you are in Connecticut.

In 1967, the Army did revist the idea of having the parts Electrolized.

Electrolizing is a form of thin dense chromium plating (TDC), It is a superior coating to hard chromium plating, it is thinner and usually does not require post treatment grinding to size like chromium plated.

[lysander]

They're supposed to be forged though.

Forging, in this case, won't do a whole lot due to the geometry of an AR bolt.

[juliet9]

Forging, in this case, won't do a whole lot due to the geometry of an AR bolt.

Forging pretty much helps everything. Of course the heat treat is equally important.

Well, I guess it comes down to if you want a coating on your bolt/carrier and if it really helps. I can see the potential benefits of lubricity and easier clean, but always the question is durability. I will say, if true as some advertise, easier clean is a major plus for me.

[markm]

I will say, if true as some advertise, easier clean is a major plus for me.

The problem is easier clean often means lube doesn't stay put. The only finish I've tried that BOTH seems easier to clean, AND keep lube where you put it is NP3. And keeping lube where it's supposed to be is WAY more important than clean up ease.

[Swstock]

There are lots of good BCGs, particularly those mentioned.

If I had to settle for 1 for all future builds, it would be a Sionics NP3.

[ABNAK]

Forging pretty much helps everything. Of course the heat treat is equally important.

Well, I guess it comes down to if you want a coating on your bolt/carrier and if it really helps. I can see the potential benefits of lubricity and easier clean, but always the question is durability. I will say, if true as some advertise, easier clean is a major plus for me.

While pretty damned expensive, the Cryptic Coatings "Mystic Black" BCG is hard to beat for cleaning. It also checks all the boxes for "The List". Member here VIP3R 237 had one he ran with 20K+ rounds before he retired it. Cleaning is really easy, even the infamous bolt tail. Again, it ain't cheap but is definitely a good product.

You can also buy components from Cryptic Coatings, like a bolt only. One of those Mystic Black bolts coupled with an LMT-E carrier would be sweet for a carbine.

[HKGuns]

The heat treat of the steel is more important when it comes to metal failures in high stress areas like bolts.

Virtually any steel with a shitty heat treat will yield a shitty bolt, even C158.