Unfortuneately there is not much you can do but either get the dog to a vet before damage is done or wait to see if it will pass, but I do not think it will pass through without causing a blockage. Trying to make the dog vomit is not an option as the bones may do more harm coming up.
The sooner you get him in for treatment the less expensive it may be. Symptoms of a blockage are sudden lack of appetite, vomiting, diarrhea (or off color/ wrong consistency stool), lethargy and possible excessive drooling.
Here is more on this.