C4 Bolt Carrier, Hard Chromed, with Sand Rail Cuts
Fully hard-chrome finished, the V1 8620 steel, full-auto weight carrier includes a proper machined Mil-Spec gas key that is chrome lined, phosphated and heat treated per the TDP and is secured to the carrier via Grade 8 fasteners and properly staked during final inspection.
Sand cuts are added for increased reliability in harsh conditions.
Obviously, “sand cuts” aren’t a new concept, we can look back to the FALs which were probably the first common firearm which used cuts to abrade, loosen, eject junk in the action. While a lot of people tend to focus on the “SAND” aspect, this style of carrier also works for weapons using cans or weapons which aren’t cleaned on a regular basis. For anyone who hasn’t used a can, not only does it get hot, it also kicks a lot of crap into the action. Cans are also heavy, make your gun longer, but they do lessen noise to a degree, and they do look sexy.
I think the hard chrome is a nice touch as well. While hard chrome might not hold lube the way parkerizing does, it does increase lubricity. Cleaning is also a nice secondary feature of hard chrome, but anyone who thinks their carrier will remain perfect and have a nice sheen is going to be sad. They do darken up eventually.
The carrier being made from good steel and having the correct staking and specs is something I would expect from Centurion Arms, so no shock there.
I saw those a while back. Had one in the cart and almost pulled the trigger. I may still, especially with one of their fine uppers. But, I’m just completely sold on the Geissele BCG’s. I have several of those and buy them whenever on sale.
Expensive for a carrier only, more than the LMT Enhanced Carrier was going for a few years ago (also with a form of sand cuts) and about what I have seen a complete Sionics NP3 BCG selling for. Trajectory Arms complete BCG is $160 and uses OCKS. A Microbest chrome BCG is $120 from Arftac so I don’t think chrome explains the price either.
It looks dope and I almost bought one, but I’ve moved pretty heavily into LMT E-BCGs, so much so that the Geissele REBCG I’ve been wanting to try doesn’t have an upper.
I’m sure it’s good and I’m sure it works, but to me this is a very low probability in the first place just based off of where I am geographically. I have yet to do some heavy shooting out in the deserts of AZ or NV, or the mountains of Utah to where sand is constant. In the woods of the Minnesota and Wisconsin the fact that I’ve run my guns in snow and mud and in dust and pine sap and they all worked great, with maybe a Tap Rack Bag to clear any debris malfunctions but those are typically magazine or ammo related.
(Edited for Update)
I did just buy another one of their regular BCG’s for $156 shipped, that’s a pretty awesome deal
I couldn’t do it. Cool enhancements, but the type of thing that needs to be priced low enough to make it the obvious choice over milspec. Basically priced same as Sionics NP3 all together with bolt and it’s good.
It’s funny you brought this up, I was going to post a thread about chrome BCG’s yesterday.
I don’t know if it’s just me, but is anyone else noticing more and more chrome BCG’s popping up? And I don’t mean from gimmicky one off brands, but I saw BRT, SOLGW, and now this one from Centurion.
I know chrome finish on BCG’s isn’t something new. I was reading one of the “Best BCG’s” threads yesterday, and somewhere in there was mention of microcracking (?) or microflaking (?) that chrome BCG’s were susceptible to.
For me the big question is: is there some sort of new method for chroming BCG’s that solved whatever “microcracking” problems used to exist? Is that the reason they’re coming back? These being from a reputable brand, I have no doubt they are well made.
I am interested in these BCG’s, especially if there’s benefits for running suppressed. I should have my first personally owned suppressors in a few months.
I hope this post didn’t detract too much from the topic. I usually default to Centurion phosphate, SOLGW, or Sionics BCG’s.
Paging Lysander, as I’m sure he can give his expertise.
Iirc the early chrome bolts had issues with hydrogen embrittlement. I’d guess the process is now refined enough that this is no longer an issue if you purchase from a reputable source.
Back to the topic, I like the idea of one and knowing how centurion arms is I have no doubts it’s a quality product.
I picked some up, and I’m not worried about the hydrogen embrittlement for two reasons. First, Monty is very knowledgeable both through his military time (R&D/ Weapon Development) as well as knowledge gained from being a part of the industry. I know he isn’t taking short cuts or skimping on things. Secondly, if there ever were an issue, I know they would take care of it ultra quick.
For myself, I have a few reasons for getting them. One, I’m a dirty pic whore. Two, I like new shiny things. Mainly, I think I’ll use them in my guns that run cans most of the time. I’m not worried about sand build up, but the crud and carbon and suppressed weapons is just plain nasty. Especially as I hate cleaning guns.
I don’t know, honestly, I have never felt the need for a chrome plated bolt.
But if I did, I would write and ask the company which SAE specification they use to plate, and the plating thickness. I would hope all of them that offer chromed bolts would use SAE AMS 2438 and a thickness between 0.0002 to 0.0005".
If you want a company to plate something with TDC, you can google “thin dense chrome” and get an impressive list of people that do that sort of thing.[/QUOTE]
I’m buying a barrel and quad from Centurion this week and was thinking about dropping one of these carriers into the cart too, but they were out of stock. Running suppressed so hence my reason for being attracted to the sand cuts and chrome. I had one of the early Young N/M BCGs and even thought it used chinese staking screws the chrome wore very well and was nice to clean. I’d like to try one on my 10.5 and see how it runs.
Hydrogen embrittlement and chromium plating mirco-cracking are two separate phenomenon.
Hydrogen embrittlement is due to hydrogen atoms infusing into the steel, not unlike nitrogen atoms when nitriding, and weakening the steel. Baking the part can drive off the hydrogen, restoring the steel properties.
Chromium plating micro-cracking is a result of internal stresses built up in side the chromium layer as it is being deposited. When hard chromium plating you are going to have micro cracks, because with that method of chromium deposition, you are going to get internal stresses inside the chrome layer. There is no refining the process to eliminate it, it is inherent in the process. You can control the size and network of the cracks but you will always have them. It the usual hard chrome applications, piston cylinders, wear rails, etc, the crack are beneficial as they retain oil.
I see some one else has covered thin dense chromium.
Same, I have ZERO qualms about going Chrome. Ive been using BRTs excellent chrome bolt carrier and LMTs enhanced bolt NOW WITH A NEW HARD CHROME COATING® with zero issues. If a company like LMT switched from whatever electroless nickle plating they were using to chrome in their flagship uber bolt Im sure its fine.
I bought one and swapped the carrier in my cm4. Anything and everything CA is excellent, top notch brand that doesn’t fk around and take the easy cheap way to doing things. Is this materially better is what those on the fence ask. For me, chrome is always best and of all the testing done by crane and mil research, chrome comes out on top. The design is fine, proven, and enhances reliability in known conditions. no brainer for me but now I have a spare carrier which as we all know…grows to full grown adolescent rifle!