CAI M70B1: Gratuitous Full Auto

    Yugoslavian AKs are very neat and stand out amongst their peers by having some very unique features. The gas cut off valve allows for rifle grenades to be fired (some folks modify this to reduce gas pressure when running a suppressor), they come equipped with night sighs, they have an RPK trunnion, thicker receiver, and I find their grips to be very comfy.

    I was looking around for a good AK candidate to convert to full auto on a form 2 for some testing, and with its rigid receiver and trunnion I decided on the M70B1. You can find them online for just over $500 and thus I would not feel guilty making one into a post dealer sample using my SOT status to make the gun a sample for law enforcement sales. I loaded 15 magazines with Brown Bear steel 7.62×39 for a total of roughly 500 rounds (we loaded some loose ammo and shot it as well).

    Converting an AKM to select fire is simple. I had a Yugo M70 parts kit and harvested the carrier, selector, and trigger group and drilled the necessary holes. You also have to cut out a section of the right guide rail so the trip lever has a place to rest. All in all it is much easier than an AR conversion, but it would be hard to do without the proper parts, jig, and drill press.

    Anyways, in the name of scientific testing, this happened:



    All in all I experienced two malfunctions. Both of which were probably a result of me messing with it (the bolt carrier failed to close all the way due to a burr preventing the trip lever from moving as freely as it should have).

    So the gun worked really well all things considered. That said, shooting this gun made me reflect on this post.The only other fully automatic AK I have ever shot was a 5.56, which reminded me of shooting my FNC. The 7.62×39 was a whole different beast. I shoot machine guns all the time, including some in 7.62×51 but this AK was ludicrously hard to keep sighted on target. While the video does not convey this well, my friend and I both agreed that it was rowdy. The AK has earned a reputation as a gun that is easy to shoot, but I cannot imagine someone with no prior experience controlling this gun very well on fun-mode. The gun also got extremely hot very quickly, more so than any other assault rifle I have played with. Obviously steel is a good conductor of heat, but I have fired 300 round from an M16 with a 10″ barrel from 10 back to back mags and that gun did not feel as hot as this one.

    However, since my friend CJ worked over some wood furniture I got from a parts kit, the heat has become less intense after trying it out several times. I think the gun turned out great! The writing on the stock says “Soviet” (I realize that Yugoslavia was technically non-aligned):





    All in all, I am very impressed with this gun, and I hope you enjoyed the video!

    Alex C.

    Alex is a Senior Writer for The Firearm Blog and Director of TFBTV.