Json giving 301 Moved Permanently

Removing the trailing slash should do the trick (most probably prior to Laravel 4.1, see below).

url: '/admin/submit-scan'

Update

As mentioned in Laravel4 POST unexplained redirect to GET

Laravel bootstrap/start.php is calling $app->redirectIfTrailingSlash(); which seems to be the culprit. This has been changed in Laravel 4.1:

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