Good morning, all. I need to learn more about BCG choices.

We have an upper receiver in 5.56 with no BCG or charging handle, and it’s time to “get started finishing” this thing.

As I stare at the Midway and Palmetto State websites this morning, I see mention of nitride and phosphate and nickel boron to start. Metallurgy is not my knowledge area, so naturally my next thought is “ask SF.”

In terms of price, the ones I see right now are all pretty similar, so that’s a good start. Beyond that, what are the advantages/disadvantages of the different metal treatments?

As use goes, this rifle will be built as a “casual plinker and occasional hunter,” rather than as a full-time use gun.

Thanks, everyone, for your help.

IMHO, you can't go wrong with a bolt made with Carpenter 158 steel (often listed as C158). That's what most USGI bolts are made of. Most C158 bolts will be phosphated, but some may have other finishes. They can be bought for reasonable cost if you shop smartly.

A lot of bolts are listed as 9310 steel, which isn't horrible, but not as good as C158. They will usually be nitrided, and also offer other finishes. Sometimes they cost more than a C158 bolt, which is puzzling to me.

Bolt carriers are available in phosphated, nitrided, nickel boron, chromed, etc. The key on a bolt carrier is to have a chrome-lined bore for the bolt and a properly-staked gas key.

Several AR part vendors offer a variety of configurations, and often information on the different options.

Good luck.

All of my AR builds have Bravo Company bolt carrier groups. 100% Mil-Spec USGI built, Carpenter 158, shot peened, chrome lined gas key and heat treated, properly staked, etc.

IIRC, it's been years, but my first build was a PSA NiBo BCG.
Definitely makes cleaning easier, everything just pretty much wipes off.

I buy these and run them really hard and haven't damaged one yet. Sometimes they're on sale for $69.

https://palmettostatearmory.co...forged-mil-spec.html

Do you plan to use it in a rifle you're suppressing?

TBH, if you’re looking for a BCG to use for plinking and occasional hunting, I wouldn’t spend a ton of money on a high end BCG. Just get one from a reputable manufacturer and make sure the carrier key is properly staked. NiBo BCGs are nice for cleaning, but that’s about it. I only have one, and that’s about the only special BCG that I ever bought. All the rest of my guns have the BCG that they came with.

quote:

Originally posted by P220 Smudge:
Do you plan to use it in a rifle you're suppressing?

Soon, yes.

Then, as per our exchange in Mar’s thread about charging handles, you’ll appreciate a carrier group that’s at least hard chromed, if not something like nickel boron of some flavor. It’s the difference between lots of soaking and scrubbing vs wiping it clean with a paper towel and some Q-tips. I’m talking hours of difference in cleaning, here.

Good to know. Thank you, Smudge!

Given that, this looks like a good choice, right?

Is this chromed enough for you?

Unless someone else knows a reason you shouldn’t go with it, I’d say it ought to do well for you, yeah. I have some Toolcraft BCG’s that are hard chromed. Nothing fancy, just basic milspec with a flat, dull gray finish and they wipe clean with ease vs my nitrided carriers. I use a mix of synthetic motor oil and grease mixed to about the consistency of honey and keep it pretty well slathered and cleanup is as easy as a wipe down with a paper towel, and if/when I want to go OCD on it, brake cleaner. Then I just re-slather it. Cleaning is a breeze now, I don’t even have to drop it in my ultrasonic.

Mind you, this is all speaking very specifically about shooting suppressed, and SBR’ed, overgassed AR’s that aren’t tuned, and until fairly recently, shooting high back pressure, traditional 60 degree baffle style cans that blow a ton of shit back into the receiver. If someone is reading this and thinks I’m nuts, but you’re shooting a mid length 16” with an A2 birdcage on the muzzle and nothing else, you cannot understand how absolutely caked in carbon I’m talking. “You don’t need all that fancy stuff” but it sure makes life a lot easier after a thousand rounds or so.

quote:

Originally posted by Mars_Attacks:
Is this chromed enough for you?

I don’t know how to answer that question. Is it?

quote:

Originally posted by vthoky:
Good to know. Thank you, Smudge!

Given that, this looks like a good choice, right?

I have that one in my 607. It's spectacular.

It's literally wipe it clean.

quote:

Originally posted by vthoky:

quote:

Originally posted by Mars_Attacks:
Is this chromed enough for you?

I don’t know how to answer that question. Is it?

LOL, not you.

The budget carrier is hard chromed in the bolt chamber.

quote:

Originally posted by vthoky:

quote:

Originally posted by P220 Smudge:
Do you plan to use it in a rifle you're suppressing?

Soon, yes.

Depending on the suppressor you are using, and the rest of the build, you may want to consider something like a Bootleg adjustable BCG. How much you need it depends on what suppressor you’re choosing, if the gun is over gassed or an SBR, lack of tunable gas system, etc. Things are super-fluid in the suppressor market right now, and it is hard to make a firm recommendation without knowing more particulars.

Yeah, I’ve heard both good and bad about the Bootleg. Friend of mine tried it out and wound up swapping it out, I can’t remember his exact complaint, but he wasn’t a fan. Griffin also makes the gas pocket carrier, which I’ve heard great things about, but nobody I know personally has tried one yet. You’re right: until vthoky buys a can, building the gun with “tuning” parts is pointless, but a carrier that wipes clean easily will be appreciated in any gun.

quote:

Originally posted by P220 Smudge:
Yeah, I’ve heard both good and bad about the Bootleg. Friend of mine tried it out and wound up swapping it out, I can’t remember his exact complaint, but he wasn’t a fan. Griffin also makes the gas pocket carrier, which I’ve heard great things about, but nobody I know personally has tried one yet. You’re right: until vthoky buys a can, building the gun with “tuning” parts is pointless, but a carrier that wipes clean easily will be appreciated in any gun.

I recently ordered a Griffin 11.5” 5.56 upper that’s going to come with the gas pocket bolt carrier, so I hope to get some experience with it in the next couple of weeks.

Oooh, definitely want to hear your thoughts on it when you get enough rounds through it. I got ahold of a blem Terra Brown Mk2 lower this past weekend and ordered their suppressor optimized buffer to go with it. A bit of a thread drift with that, but I’m bringing it back by saying I want to eventually see how it runs with my 10.3 and 11.5 URGI uppers and possibly throw a gas pocket carrier in there, depending on what upper end can combo I end up going with.