Search for the article on the 17squirrel cartridge here on the site. In it you will find more information than necessary.
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http://www.saubier.com/smallcaliber/17squirrel.pdf
http://www.saubier.com/smallcaliber/17squirrel.pdf
The short answer is that this is a good match for the cartridge & you can probably reach 3650fps* (edit from earlier), using the appropriate powders mentioned in the article, (dependent on your barrel length).
Your 38 Cooper probably can maxamize the potential of this cartride.