AR-15: Bolt Carrier Group and Rear Sight

With the lower and upper in my possession, I started looking for a bolt carrier group (BCG) so that I can get my new firearm to go BOOM and a rear sight so I could aim the firearm properly. Again, I perused the Calguns boards for weeks and contacted a number of sellers who were selling used BCG's and rear sights.

The BCG

As a reference point, brand new ones run about $130 to $150 for a standard quality BCG. The used ones I were finding for sale were running about $110. At this rate, I didn't believe I was getting enough of a discount to warrant buying used. I'd rather spend the extra $20 for new. However, as luck would have it, a seller who was offering to sell an "enhanced" LMT BCG showed up right as I was about to buy new.

The seller informed me that the BCG had an enhanced extractor (i.e., it was more robust than a standard extractor) and only had 150 rounds shot through it. He offered to sell it to me for much less than the other sellers were asking for, so I decided to purchase it from him.

Another key point that made me decide to purchase it was that the BCG was made by LMT. Given that my upper was from LMT as well, I felt that buying from the same brand would ensure that the parts would work well together. As this is my first build, I wanted to minimize any potential headaches.

The Rear Sight

As for the rear sight, I was initially looking to pick up a Magpul Back-Up Sight (MBUS). Don't hate me for saying this, but since the AR-15 had Magpul stock and handguards, I thought I'd round out the Magpul accessories with a matching rear sight. There were lots of people selling the MBUS; but after seeing them at a firearm shop, I decided to go a different direction.

MBUS sights are meant to be back-up sights (hence the name) and fold down to allow the shooter to use optics. With this being my first AR-15, I wanted to learn to shoot with iron sights first before considering optics. Besides, good optics run about $500 and that clearly was not within budget.

I changed my search criteria and started looking for a good dedicated iron sight. Much like the LMT BCG I acquired, I lucked into finding a LMT Tactical Rear Sight.

This sight typically sells for $120, but I was able to purchase it for less than half. In fact, it's a brand new sight, so I really scored a good deal.

I have to say that I've been very fortunate with my AR-15 build. All the parts that I've been able to purchase thus far have been from high-quality manufacturers...and I've been getting them at very good prices. I have a feeling that it's partly luck (I've been spotting these deals as they hit the forum board) and partly that people are selling off their firearms as they feel the pinch of the economy. In any case, I'm well within my budget for my first AR-15.