Casting weighted flies is always A challenge and never fun. BUT! You do need to get down to the fish. When casting weighted flies you need to slow down. You know you are not slow enough when the fly goes careening off the top of your head. With a weighted fly you should feel A deffinet tug when the line straightens out behind you. That is when you start the foreward cast. Oh yes, you also need to throw A big open loop. Put these two thing together and your there. If you have done any Spay casting you can also use a Single Spay or a Snap-T cast with your single handed rod as long as your not throwing A lot of lead.
The Spay casts I mentioned are good to know because no matter what you are throwing they give you some options during the course of A long day. They will give you A chance to rest your tired and sore shoulder and wrist. It is well worth the time and effort to learn. Give me A holler if you want to discuss any further.