Cropping images - pasting to new layer - layer boundary size

[rich2005]

Not too sure about your selection method but it seems to be something like this

A new layer (red) pasted in but coin needs to be same size as base layer.
screenshot(s) http://i.imgur.com/rltGQzm.jpg

Layer is scaled to size but layer boundary (yellow dotted boundary) is now larger than the canvas size. http://i.imgur.com/I6CxcDQ.jpg

Use layer to image size crops the layer to the canvas size http://i.imgur.com/wJLbNDu.jpg

results in matching layer(s) http://i.imgur.com/WnDoY1p.jpg