I had this gun as well. I went to the musket cap like you mentioned HM. It is easy to take apart and clean IF
you do this on a regular basis. When I first got my hands on this ML it was corroded like crazy.. I had to change the nipple out that is why I went with the musket over the No.11 cap.
I wrote a short review on this ML. One of my cons of the ML was that is not as easy to clean as the more modern ML's. But Im comparing that to a T/C Triumph that has a breech plug you just remove with your hand or at worst a quick 1/4 turn with a tool. http://www.deerhuntersclub.com/hunti...loader-review/
You can get the musket nipple for about 5 or 6 bucks.
Great ML that was very accurate. Just take the time to clean every time you go out to the range. If you let it sit you will be beating it against the wall screaming at it.