OK, so this isn't my 102, it's my buddy's. I haven't even ordered one yet, but I probably will. Him and his wife just had his third kid and he won't be shooting it anytime soon so he left a bunch of his stuff at my place to mess around with. I'll be using his his as a guinea pig, lol!
He's collected a few parts here and there, and though these aftermarket mods wouldn't be my first choice, it's nice to have to play around with, see how things work, how certain things fit.
It should be noted that he already installed a Trigger Tech trigger, so I have no idea how the original trigger felt. My buddy typically shoots his bolt guns and isn't really an AR guy, so he's pretty particular about having a smooth light trigger that breaks nicely. He said he hated the factory trigger on the 102. I'll have to bug him about the details next time. The Trigger Tech feels pretty awesome though, nice clean break. Sorry, I didn't check to see how many pounds it breaks at, but it is definitely lighter than any of the mil-spec triggers I have.
So, the mag release appears to be non-ambi on this one. It's supposed to be a Gen II, and you can tell because it doesn't have the integrated trigger guard. It's just a standard style one that you can swap out to whatever you want. Plain A2 grip.
The factor selector is pretty crappy. It almost feels sticky, but I'm not sure if that has to do with his trigger swap. I didn't get a chance to feel it before he swapped it out, but he said it was always like that.
The factory BCL butt stock is pretty hideous. It looks like it took some design cues from Magpul, but didn't get it quite right.
My pal ended up picking up two barrels, a Ballistic Advantage 18" in 6.5cm barrel and Christiansen Arms Carbon Fibre in .308. I suggested he shoot the factory barrel first, see if it's any good, but as he already bought the aftermarket ones, he didn't want to bother.
For glass, he ended up with this Trijicon unit. To be honest, I haven't even looked through it or know which model it is. Will have to get more details on this later.
He decided to go with a Gen3 Magpul PRS stock. I had the Gen 1 and really liked it, so I can see how this would be a good pic. This model fits both regular carbine and rifle length receiver extensions.
Raptor charging handle. Looks pretty, works fine, just not my cup of tea.
Again, looks pretty, but would not be my first choice in aftermarket selector switches.
The first thing I noticed about the hand guard was the shape of it appears proprietary to the BCL upper receiver. Any aftermarket one not shaped not specifically made for the 102 will likely leave some sort of gap and might not look right. The screws are countersunk, but are not countersunk deep enough, but honestly it's hard to expect much when you have a round surface and flat top screw.
The barrel nut assembly appears to be proprietary to BCL, however as many here have stated before, it is an Armalite AR-10 thread pattern, so if you are going to order an aftermarket hand guard for your 102, make sure it has an Armalite pattern barrel nut. The height and profile of the hand guard will be another matter that needs to be figured out. I think I read somewhere to order a "high" profile hand guard, but I'll have to figure this out when the time comes.
The gas block came of easily enough, just two simple Allen screws.
As I understand it, previous NEAs had this design where the rear take down detent spring was not behind the rear plate, but captured by the grip. I'm not sure if this is typical of AR-10/AR308s or just an NEA/BCL thing. Anyway, the A2 grip came off in favour of an Ergo grip, plus we had to get that selector switch in anyway.
A comparison of a standard AR-15 carbine receiver extension with the BCL unit. The BCL one is longer, and the receiver extension locking ring on the 102 appears taller and possibly had a wider outside diameter.
As mentioned the PRS stock is supposed to be able to install onto both carbine and rifle length receiver extensions. The adapter for the carbine stock fit one of my ARs (though not completely seated in the picture) just fine.
It did not fit the 102 in any way we could figure out. I suppose we could have removed material from the Magpul adapter, but we had a 308 rifle length receiver extension anyway, so off came the BCL tube.
The nut came off with a standard AR tool, pretty straight forward.
The receiver extension was made for an LR-308, and though it should have fit a standard A2 butt stock, we never tried it. I have no idea if there is any difference between an Armalite pattern and DPMS pattern receiver extension, buffer and spring, but since it fit and it was all we had, on it went.
After that, it was just a matter of slipping on the PRS stock.
The Raptor charging handle was not a simple fit, and I think this has been addressed. The profile of the little tabs on the factory BCL unit are smaller, and rounder, so the tabs on the Raptor had to be filed down to fit. I understand that BCL may have addressed this issue and future uppers should fit aftermarket charging handles better?
The Ballistic Advantage barrel on the left, the Christiansen Arms carbon fibre barrel in the middle and the factory BCL barrel on the right.
Thanks to FMJ's advice, we picked up a Brownells barrel extension torque tool. I don't even have one of these for my ARs, but I'm thinking about getting one. Definitely handy to have. It locks down the barrel (with the aid of a breaker bar or socket wrench) so you don't put any unnecessary strain on the receiver itself.
I think FMJ read somewhere the size of the BCL nut was 1 3/16, but we just ended up getting the biggest adjustable wrench we could find. I think I would have preferred the right size wrench, but Crappy Tire was sold out and all they had was the big adjustable wrench.
The sleeve for the BCL hand guard came off with the nut, but once the nut was loose, the sleeve spun freely.
We decided to throw the carbon fibre barrel on, and we should have weighed them, but to be honest, the weight saves really felt negligible.
The ledge where the gas block sits on the Christiansen Arms barrel sat further back slightly.
As a result, the gas tube would sit deeper in the upper receiver. I'm not sure if this is going to be an issue later on.
The factory BCL gas block fit around the Ballistic Advantage barrel perfectly, but would not fit the Christiansen Arms cf barrel, but it came with their own gas block and gas tube anyway. At least if we decide to try the 6.5 barrel later on, we can use the BCL gas block and tube.
Fit like a glove.
We had no idea what torque specs are called for the barrel nut, and we had to struggle a bit to time the hand guard sleeve while cranking on the barrel nut. Anyway, it's all coming off again when my buddy orders an aftermarket hand guard.
Both of us are looking for quad rails for that old school look like on the M11 Mod 0
or the Armalite SASS:
I've heard the KAC unit will not fit (DPMS pattern barrel nut?) but I'm hoping the rail from the Armalite will. Either way, I'll have to do more research.
Anyway, that's all to report for now, it will probably be a while before we have time to shoot this thing. More likely than not more mods will be done before we take it out for a test drive. Stay tuned :)