[Quicksilvergoat]

My best advice is contact Eberlestock. I recently looked at a ton of their packs and this is probably one of the few I didn't fondle. I ended up with an Operator. I believe all of their buttcovers are adjustable length wise. I didn't see any that weren't. Even the smaller scabbard that they sell seperately has an optional butt cover you can buy and it extends. I really think with the widemouth you should be fine. Reading on their site I think it's designed with what you have in mind. The scabbard is pretty wide on the Operator. It doesn't taper until the very bottom. The butt cover is going to be the same width as the scabbard. Hope this helps.

 

[Frankstonalum]

Yeah that operator is a nice pack, it is actually the other one I am looking at if the dragonfly won't fit my rifle. The only thing holding me back on the operator is the dragonfly's ability to go from a good day pack for light loads at the start and the ability to expand to a hauler at the end of the day. I agree I'll have to get in touch with them after the holiday.

 

[Quicksilvergoat]

Depends on what your goal is but you may want to check out the phantom. It has a sizable scabbard which is detachable and there is one for sale here on the forum.