I am considering buying the CountryLine PHD (model 24045500) sold at TSC. Does anyone know if my B7100HST will handle this? With this SCUT is there a limit on the size of the auger I should use? Thanks.
My dad's B8200 handles a 9" auger just fine, and it's not much bigger. I don't think I've ever heard it even snort the engine, so I don't doubt it could handle a larger auger. Your question really depends on your soil type. If you want to spin a 24" or larger bit in heavy soil, you are probably out of luck. Large rocks and tree roots will be a pain on any auger on a farm tractor without downforce and a reverse direction on the PTO.
I don't know if you've used a tractor mounted auger before, so I'll give you my standard advise. Pack the wrenches to unfasten the auger mounting bolt and a large pipe wrench to unscrew the auger from the ground if it gets stuck on a root and corkscrews in. I'd also advise taking a manual post hole digger to make a small "starter" hole to allow the bit to start cleanly, otherwise it will tend to skip around a bit before it bites in. This will help keep your holes in a line. You also want to learn how much angle you need to have in the auger when you start digging, as the pivot action as the auger lowers tilts the auger as it goes down. They are a very nice tool to use, and you'll be used to it in no time. Best of luck!
The problem I've found isn't power but lift height of the 3pt, my B2620 will barely lift the auger high enough to allow traveling. Mine is a Leinbach 7300 so its a little big for the tractor so that is part of the problem, the 7100 is decent size (little bigger than what I consider a SCUT) so I doubt it will have any problem with the Countryline.
As far as what size auger, I would say you'll have no problem running a 12in in most of the soil in MD, if your in sandy southern MD I'd say maybe even 24in would be doable, maybe 18in max in heavier clay as long as its not too rocky.