For large body rifle brass like the 338 RCM, you may need to trim .26" minimum off the end of funnel to work with the large body of the 338 RCM. A belt sander or cut off blade in Dremel tool will make quick work of this. If you would prefer us to make the adjustment, we can. Please return funnel and a sample case, and we will make the adjustment for you. https://leeprecision.com/files/instruct/returnform.pdf
