If you have the reloading equipment that will allow you to start substituting components why are you not developing your own loads? At your level of experience I don't think it would be wise to start experimenting on your own. For example, in your second question about substituting lighter bullets the powder in the case may not be well suited to the lighter weight of bullet. It might work, but then again it might not and if so, what have you gotten for your efforts?
I think you have to make a choice. Either stick to factory ammo or else get into reloading, read and understand the manuals and develope the experience to tune ammo to your gun.
Just remember, the advice may be worth just what you paid for it.
Jim
