Apache mod_rewrite Take @2x out of image request uri

For an acute server crash problem, I'm trying to match any request for @2x retina style images, and rewrite it to the non-@2x equivalent.

First I want to check this is such a request:

# NOTES: Check the file name to see if it matches the @2x pattern:
RewriteCond %{REQUEST_FILENAME} ^(.*)(@2x\.\w+)$ [NC]

For example:

media/catalog/product/cache/1/thumbnail/100x/9df78eadfvrtdfgdfg6e5fb8d27136e95/i/n/[email protected]

Then I need to just take out @2x and return:

media/catalog/product/cache/1/thumbnail/100x/9df78eadfvrtdfgdfg6e5fb8d27136e95/i/n/insample-123_1.jpg

Could be png or jpeg or PNG or gif etc.

I'm no RegExp ninja. I know how to replace parts, but not remove. Can anyone please assist? My servers are dying because of 404's...

EDIT: Seems like it's:

RewriteCond %{REQUEST_FILENAME} ^(.*)(@2x\.\w+)$ [NC]
RewriteRule (.+)@2x\.(\w+)$ $1.$2 [R=302]