I wanted to offer my thoughts on a product that I received from Prime Weaponry. This company is fairly new to the market and offers just BCGs and associated parts at this time. I realized I was taking some risk in trying a BCG from a new company in the market, but they offered a good deal on a DLC coated BCG, so I thought I would try it.
As of mid-2015 I do not recommend this company or this product. I know that BCM, AIM, PSA and many other well established suppliers would have supplied a serviceable part with very little risk of a lemon, but I let enthusiasm to try the diamond like carbon coating override my better judgment.
For folks that might not have used anything with a DLC coating; it is a phenomenal bonded coating that when done correctly beats the specifications on any other coating material I know of including NiB. As an oversimplification of the process it is a carbon based coating that is deposited in a vacuum on the base material and could have properties very closely matching that of a diamond. I use the term “could” as the carbon materials can vary based on intended properties of the final product and the actual process for deposition can be done in a number of manners. I use a few items that are DLC coated and they never fail to impress from a durability perspective.
The BCG arrived 4 days after I ordered it, so no issues there, packing was good and from a distance everything looked good. Looking at the BCG critically I found the following things that I did not really expect for this price point. First a few minor things:
1. The ramp for the hammer on the carrier has a distinct machine line I can see and feel. This runs in the same direction of travel as the carrier moves so it likely would not cause any failure just some unnecessary matching part wear
2. One of the lower bearing rails on the carrierhas a very minor bur. It looks like the machined edge was hit by something and turned out a bur. It might make a corresponding scratch in the upper, but I doubt it is enough to really be an issue other than a scratch.
3. The bolt did not seem to be moving as I would have expected. On inspection the gas rings were just awful, and wedged on the bolt. After taking them off it is clear they are concaved (dull tooling?). The ID of a gas ring is off center by design, but should be consistent from ring to ring. These were each a bit different and none matched to any of the new ones in my parts bin. I believe if installed with the concave shapes aligned they would likely function. I installed a new set.
Now the issues that I think disqualifies this as a “good to go”product
4. After replacing the rings I soaked the bolt with oil and hand worked the bolt in the carrier to make sure the rings were seated. I realize this is not necessary, it is just a habit. Without ever going into an upper or seeing a single round the DLC on the cam pin is worn through and a silver wear line is visible. The carrier slot for the cam pin is also worn to a light brown and looks like it will be completely devoid of coating in less than a few dozen additional cycles. Not what I expected for a coating sold as significantly harder and with a lower friction number than NiB.
5. I looked a bit harder at the gas chamber. The DLC coating does not reach the gas chamber inside the bolt carrier and there is no evidence of any lining at all (e.g. chrome, melonite or DLC). It presents the way a bad spray paint job would look over a deep recess. At this price one would expect some lining of the carrier.
The positives:
6. Firing pin looks perfect and the retaining pin (cotter pin) is sized properly and beveled
7. The machine work on the bolt & extractor is perfect and it is marked as MPI
8. Although the extractor spring looks like it was bent while being ground it includes an o ring and insert
Frankly the only specification on this BCG that you’re paying a premium for is the DLC coating. I can make suppositions on the QC issues, but it really does not matter, these are not at a quality level commensurate with price (on sale for 139) and the coating at best would be characterized as questionable.
DLC and NiB may be solutions looking for a problem to many folks. I was hoping to find a product similar to a Cryptic BCG at a better price point. That did not work out for me with this company.
Prime is not responding to my questions on this issue. If they eventually do I will update with their answer.
As of mid-2015 I do not recommend this company or this product. I know that BCM, AIM, PSA and many other well established suppliers would have supplied a serviceable part with very little risk of a lemon, but I let enthusiasm to try the diamond like carbon coating override my better judgment.
For folks that might not have used anything with a DLC coating; it is a phenomenal bonded coating that when done correctly beats the specifications on any other coating material I know of including NiB. As an oversimplification of the process it is a carbon based coating that is deposited in a vacuum on the base material and could have properties very closely matching that of a diamond. I use the term “could” as the carbon materials can vary based on intended properties of the final product and the actual process for deposition can be done in a number of manners. I use a few items that are DLC coated and they never fail to impress from a durability perspective.
The BCG arrived 4 days after I ordered it, so no issues there, packing was good and from a distance everything looked good. Looking at the BCG critically I found the following things that I did not really expect for this price point. First a few minor things:
1. The ramp for the hammer on the carrier has a distinct machine line I can see and feel. This runs in the same direction of travel as the carrier moves so it likely would not cause any failure just some unnecessary matching part wear
2. One of the lower bearing rails on the carrierhas a very minor bur. It looks like the machined edge was hit by something and turned out a bur. It might make a corresponding scratch in the upper, but I doubt it is enough to really be an issue other than a scratch.
3. The bolt did not seem to be moving as I would have expected. On inspection the gas rings were just awful, and wedged on the bolt. After taking them off it is clear they are concaved (dull tooling?). The ID of a gas ring is off center by design, but should be consistent from ring to ring. These were each a bit different and none matched to any of the new ones in my parts bin. I believe if installed with the concave shapes aligned they would likely function. I installed a new set.
Now the issues that I think disqualifies this as a “good to go”product
4. After replacing the rings I soaked the bolt with oil and hand worked the bolt in the carrier to make sure the rings were seated. I realize this is not necessary, it is just a habit. Without ever going into an upper or seeing a single round the DLC on the cam pin is worn through and a silver wear line is visible. The carrier slot for the cam pin is also worn to a light brown and looks like it will be completely devoid of coating in less than a few dozen additional cycles. Not what I expected for a coating sold as significantly harder and with a lower friction number than NiB.
5. I looked a bit harder at the gas chamber. The DLC coating does not reach the gas chamber inside the bolt carrier and there is no evidence of any lining at all (e.g. chrome, melonite or DLC). It presents the way a bad spray paint job would look over a deep recess. At this price one would expect some lining of the carrier.
The positives:
6. Firing pin looks perfect and the retaining pin (cotter pin) is sized properly and beveled
7. The machine work on the bolt & extractor is perfect and it is marked as MPI
8. Although the extractor spring looks like it was bent while being ground it includes an o ring and insert
Frankly the only specification on this BCG that you’re paying a premium for is the DLC coating. I can make suppositions on the QC issues, but it really does not matter, these are not at a quality level commensurate with price (on sale for 139) and the coating at best would be characterized as questionable.
DLC and NiB may be solutions looking for a problem to many folks. I was hoping to find a product similar to a Cryptic BCG at a better price point. That did not work out for me with this company.
Prime is not responding to my questions on this issue. If they eventually do I will update with their answer.
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