ORIGINAL: eldeguello
CCI makes two different caps in No. 11 size-"standard" and MAGNUM. The magnum caps are labelled as such on the tin. The CCI Magnum No. 11's are plenty hot, as are RWS caps. And the NEW Remington No. 11's are a big improvement over the old ones.
IF you want really hot, go to October Country's website and buy a Mag-Sparknipple to replace your standard nipple, and use No. 209 shotgun primers.
http://octobercountry.com/products3.php?productid=395
The one shown here is metric. But I purchased mine from the manufacturer, Hubbard Outdoor Products, and they havce 1/4X28and U.S. musket thread sizes as well.
Thanks for that info Elde! It's going in a folder for later reference/purchase.