well i recently purchased a core-15 NiB BCG and figured id write this to give my opinion on them.

im going to start this off with the bad and get that out of the way. there isnt a whole lot wrong with this BCG but there are two main things.

first off is the gas key screws and staking


it uses the incorrect screws, not that it matters but its something some may want. also the staking is not the best but it is staked well enough to never come loose.
the odd thing about the gas key screws is that they use the correct screws on their standard BCG's but not the NiB, no telling what thats about.(ETA: this was cleared up as an issue with FZ not Core 15)

the other bad thing is the lack of extractor o-ring


while this isnt a big deal its something alot of people want in their rifles. so while this will do the job fine i recommend upgrading to the BCM spring and o-ring if its soething you feel is needed in a BCG

now lets talk about the good.

first off is the price. for $170 you get a killer deal on a good NiB BCG.
its a full auto carrier that is identical to all my others except its NiB. its also one of the cheapest NiB BCG's ive seen that is as high quality as this is.

it comes with a large spool firing pin, correct extractor spring and insert as well as everything most BCG's come with. the NiB BCG is very smooth and works very well in my rifle.
it definitely increases the ability to fire without lube and is much smoother than other BCG's, it also has a slight slick feeling to it almost like there is a small amount of lube on it.
it runs great, in my limited use it really does seem to slide better and truly becomes slick with some lube applied to it, the best part is the cleanup.

all it takes is a rag to clean this BCG, basically nothing sticks to the coating allowing for a quick easy cleanup with minimal tools.





so far i have 600rnds through it and i couldnt be happier, the price of $170 is just right and unbeatable. if you are looking for a good affordable NiB BCG this is the one for you.

the good outweighs the bad in this case, and the bad may not really be a big deal but only time and use will tell. if you are on the fence about getting a new BCG and can afford the $170 i highly recommend this BCG to anyone

if you have any questions feel free to ask, and im sorry if this is a bit short, its late, im tired, and a little delirious

That picture shows the extractor insert is there...

I also wouldn't use the o-ring with a BCM extractor spring unless there was some demonstrated need to do so. The extra power extractor springs don't typically require the o-ring, and having too much extractor tension can cause just as many problems as not having enough.

I see no problems with the insert, bolts, or the staking.

Insert is there,  the staking looks good.  I see the screws they used take a larger allen wrench (not sure it matters) than my DD and Spikes BCGs.

Thanks for bringing hat up i mean the lack of o-ring that alot of people feel is necessary ill edit the post,

Like i said it was late lol

Overall though its an incredible BCG for the price and id recommend it to anyone

ETA: edited for clarity about the extractor.

Thanks for the clarification, your staking job is more than enough in my opinion as it did displace metal against the screws.

Some may find it lacking compared to brands like DD, but in my opinion i dont see your staking job ever causing an issue.

I try to look at this from a perspective of a general audience, ive seen alot of different things posted abou what is and isnt correct, or what is and isnt needed.
All that said the bad i listed isnt really bad persay. Its more of something to look at and decide if your happy with it.

In my case im perfectly fine with the screw, staking, and lack of o-ring, but i know there are some who want it to be exactly like brand A, so i wanted to point out the different things.

So IMO looking at it through my perspective everything is perfect

Is the bolt MPI?


I would need to see correct key screws, proper staking, and some sort of remnant of an MPI stamping before I would buy one. $170 is a good price for a NiB BCG with all of the right features, but for $200 I can buy a Spike's that has all of the right features, without a doubt. I don't own a Spike's BCG of any kind.... just saying.

For ME MP bolts are a must have for a SD carbine/rifle
For range,hunting, not so much.

The Oring no big deal

Hell I never had any problems with the blue or black insert

Looks Good to me ––Thanks for the review

They are MPI and HPT tested, just not stamped.

DD also doesnt stamp their BCG's with that info, but the only Real thing i noticed was the screws, that shouldnt ever be a problem.

Core-15 did state thats a FZ issue and in the future will be fixed, so buy with confidence

Also dont forget it comes with a LIFETIME warranty

Not true.  Cleanup is easier, but carbon will stick to it and you will still need a cleaner.

Im just giving my experiences, the carbon jut wiped off, i did have CLP on it before using it.

ETA: this came up through an im, the bolt carrier does not have a logo of any kind on it, which is nice for those who hate BCG logos

This is from the Core15 new product thread.

Batch testing is kind of a killer for me.  I do love NiB though, I'll never own a BCG without it.  My BCG has never received a drop of lube and I have never experienced a malfunction related to it.  95% of the build up will wipe off but will still need some chemical help.  If you use qualifity ammo and have a strict cleaning regimen you may be able to get buy without but I couldn't.(I use wolf occasionally and don't clean every time out when I get back, but I'm not anal about it)

What NiB BCGs do you currently own?

I emailed core 15, all NiB BCG are MPI and HP batch tested