+1 to Ultimak http://ultimak.com/pic2.htm It solves many problems common to AK-47. Very common thing, binding gas tube, is solved with Ultimak, at least with little grinding.
Attachment to barrel provides usually stable enough platform for mounting optics. But, if barrel does bend when heated up (pretty common thing in some AK:s), it does not help.
If you install lower handguard part also, make sure it will not bind the barrel. Just in case you want to hit something and not only kick dust

Yes, I worked with hundreds of AK:s, AKS:s etc. before Northern Europe got their AR-15 boom