That sounds about right to me. Honestly, it's hard to say what a good weight is because it depends on the dog. As long as he is not too skinny and he is not obese, then he is developing normally and his food is at the right amount. I keep an eye on my pup's body weight versus their frame more than anything else when they're growing.
There are some charts that people have made, but most pups don't actually fit on them. Mine was about 20 pounds at 4 months which I think the chart said made him a dwarf D: But he's a happy healthy 60 pounds now and still growing!
My best advice is to keep an eye on his body weight and make sure he doesn't get fat. I actually like to keep my pups on the lean side. In my experience, it helps keep them from getting quite so many growth spurts and it keeps them light so their weight doesn't put too much stress on their joints.