To be quite honest,I'm kinda disappointed with both JVPC and Sandeep.
Look at 9:20,there's a 'Stovepipe' jam in JVPC (with Nickel-Boron-Nitrite finish).
Later,in same video,around 10:50,there is either failure to feed or failure to fire (due to bad primer,i guess) in JVPC without Nickel-Boron-Nitrite finish.
I mean after all these years,how could they f**k it up ? INSAS family of firearms are already infamous for having bad reliability,and now this.
I'm disappointed with Sandeep because he's showing this up.
I think rate of fire of this gun is somewhat higher,which is causing this stovepipe.My guess is that they didn't put 'Hammer Retarder' or 'Rate Reducer' in JVPC's trigger group,which could potentially reduce chances of such jams.
This is how it looks.
This is how it works.
Video
Animated Video of AKM which has shown rate reducer operation
Description with images.
www.weaponeer.net/forum/forum_posts.asp?TID=8365
It might happen due to issues with recoil spring,as well.