Hmmm interesting. I was messing around with my x-150 to see if the recoil pad on my 30-30 would fit, which it didnt. But i found my stock was solid except for a 1" hole drilled through the middle of the stock that went for maybe 6-7 inchs. Im thinking about a custom recoil pad with a hole in it and a trap door, Kind of like on the SKS assult rifle and find a bottle and put a little stash of cleaning supplies in there.