You've got a few problems at play here.
First, and most importantly...you said your shelf is flat. The bow was never made to be shot off the shelf. Is was made to be shot off an elevated rest. A flat shelf on a recurve is a dead give a way to this. When you try to shoot a bow like that off the shelf you've got a TON of contact and the bow will be out of tiller.
I see a lot of guys shooting old Wings, Pearsons, and some Roots like this. BAD idea. Their arrows always fly like crap and their rugs are worn horribly.
You've got a few choices here. You can build up the shelf to make it radiused and get the arrow higher so you're pulling where the bow was tillered for. This can be done with leather, hard felt, etc.
You can also use a stick-on rest. Flipper's are a good choice, but bristle rests and feather rests are also available and will give you that "off the shelf" feeling. Check out Black Widow for the bristle rests, and Three Rivers for the feather rests.
First things first...get that shelf situation taken care of and get your nock point set so that there is NO porpoise of the arrow.
Next, you may have a spine issue as well causing the arrow to contact the strike plate upon release. Once you get the shelf addressed and eliminate any porpoise of the arrow you can check for fish-tailing and adjust your shaft length, brace height, and/or point weight as needed.
JRW
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