If you have been following along with some of the articles and reviews I have written about Imperial Arms Co., then you know they have been making receivers and components for the SCAR 17S platform. Nate at Imperial Arms Co. was kind enough to send out his new BBC (Buffered Bolt Carrier) for the SCAR 17S for this review. Why would you want a BBC for your SCAR 17S platform? Well, read and find out.

Imperial Arms Co. @TFB

• Imperial Arms Co. Buffered Bolt Carrier For SCAR 17/20
• TFB Review: Imperial Arms Co. MTM – SCAR Go FRT
• TFB Review: Imperial Arms Co New SCAR17S Upgrades

Back in August, Imperial Arms Co. announced their new buffered bolt carrier. The BBC is an upgrade for anyone with a SCAR 17S or SCAR 20S. Imperial Arms Co. designed their BBC to be compatible with FN’s new NRCH (non reciprocating charging handle) SCAR17S. So for those of you, like me, who have an older SCAR 17S that does not have the NRCH system, the Imperial Arms Co. BBC will upgrade you to an NRCH. However, it is not a simple bolt carrier swap.

Factory FN 17S carrier on top, IAC BBC on the bottom.

The IAC BBC is a two-piece carrier. The NRCH is a sled that the actual carrier slides into.

Photo by Imperial Arms Co.

Here is a close-up of the NRCH mechanism. That sprung latch grabs onto the leading edge of the bolt carrier.

When the BBC is closed in battery, that latch grabs onto a pin in the front end plate. Imperial Arms recommends getting Fernilab’s SCAR Unobtrusive Plate. The NRCH version has a pin that is drifted across the gap you see in the image below. This is what allows the NRCH to lock the charging handle while the bolt reciprocates under fire.

Here is the back and bottom of the IAC BBC. You can see the roll pin in the bottom left corner. That is for tripping Imperial Arms Co’s sled for forced reset or if you have an FFL/SOT, a post-sample MTM with M16 fire control and sear.

Besides the roll pin, the buffer is the more important feature of the IAC BBC. It is that large cylinder sticking out the back.

According to Imperial Arms Co.:

Hydraulically buffered configuration greatly reduces wear on the receiver and mititgates backplate screw canting, even under the harshest, overgassed and suppressed conditions.  Allows the use of high backpressure suppresors typically forbidden on the Scar(tm) platform.

IAC BBC in Motion

Here is a slow-motion video I captured comparing a factory SCAR 17S recoil impulse vs the Imperial Arms Co. BBC in my CypherX.

We used my friend’s SCAR 17S and his Elcan SpectreDR. In the past, we noticed the SpectreDR moves a lot under recoil due to how the scope is held in place under spring tension to zero the optic. Watch carefully. The black SCAR 17S in the beginning is a factory SCAR 17S setup and there is movement when the round is fired. There is a second event when the factory carrier hits the back of the receiver. Then another shimmy when the bolt closes.

Now carefully watch the next video clip with the IAC BBC. There is still a recoil event when the round is fired. But I did not see any movement when the bolt reached the end of its travel. The hydraulic buffer did its job. There does seem to be a micro movement when the bolt closes but it is a lot smaller than without the buffer bolt carrier.

Final Thoughts On the IAC BBC

When I am shooting my SCAR 17S Cypher X with the IAC BBC, the recoil impulse feels stretched out and not as snappy especially when I am shooting suppressed. The slow-motion video really amazed me at how little movement there is due to the buffered bolt carrier.

When I am shooting rapidly, the SCAR 17S feels more manageable. When we tried the Imperial Arms Co MTM with a forced reset trigger, the gun pushed us around and was difficult to control the recoil. Not the case with the buffered bolt carrier.

Imperial Arms Co’s buffered bolt carrier comes out soon and retails for $799.99. Not that bad considering you can upgrade to NRCH. My friends Kythe and Jerry both have Handl Defense hand guards and due to the design, the handguard bolts into a proprietary end plate. The NRCH charging sled interferes with these end plates and will not work. You would need to modify them if you wanted to use the buffered bolt carrier.

Soon I will be using the IAC BBC in conjunction with the Lingle Industries caliber conversion kit. I will be switching from 7.62×51 to 5.56×45. We shall see what the factory carrier and IAC BBC do under 5.56.