When I make a squirrel call, I'll bore a 9/32" hole about 1-1/4" in length. Then I'll epoxy in a JC Products tapered sleeve. The sleeve will hold the JC Products reed (I believe it's a 005). For the bore of the call, I like a 5/8" diameter hole, that butts up against the 9/32" one. The tapered sleeve is seated right to the beginning of the 5/8" hole. I also use the small 3 tier bellows on my calls. I'll blade the reed, then carefully insert it into the metal sleeve. Then I'll slip the bellow over the dovetailed tenon I use at the mouth end of the call. The "V" shaped (dovetailed) tenon has a couple grooves turned around it to give the rubber ridge in the bellow end some where to sit. I've found that a shorter barreled calls seems to sound more squirrel like in my estimation. So watch the overall length. Hope this helps?
HuntnCarve
Dave