RWTF, The gun that I moved the POI on was a .410 that was F&F and both barrels POI was off by over 8" in different directions. I don't have a choke mike that will go in a .410 so I did it totally by shooting patterns and burned up about 2 boxes of shells, as Jent pointed out if you do something like this yourself the single most important thing is to go slow and constantly check the result you are getting. As for reamers I just have a cheaper set that more than covers all the gauges that I bought from harbor freight, some will say you have to buy the top of the line from brownells or a tool Co. but for older guns I haven't found the barrel steel to be that hard that what I have doesn't work just fine. As for bore pilot bushings, I have done all the chokes I have done from the front and here again the key seems to be the very lightest cuts you can take and constant patterning and I have not had a problem with moving the POI when I didn't want to. RWTF, if you are asking about cleaning up the length of the bore I would get a piece of dowel and wrap some emery paper on it or buy a bore hone and use a drill to clean up the bore, not a reamer.
