Mass Rocket Stove burn (fire height in heat riser) Question

Let me start by saying this is the first RMH I have built, an so far I have the J tube built.

all built out of 5X5 steel tube.

My Feed tube is 7 inch, burn Tunnel is 7 and the heat riser is 24 inchs ( I started with 36 inches).

I have not insulated anything yet.

so when I fire the stove I get a good draw and the Rocket sound but the fire is hardly makeing it out of the burn tunnel, I thought the fire was going to be up in the hear riser.

is this normal or is there something I did wrong.

thanks

Tom

Add the insulation and it will ! At the moment you're only burning the wood and not getting hot enough for the after burn