I made my own handle and you don't want to run a carbide trimmer on a drill press or anything else that spins it real fast.You will quickly end up with really really short brass.Carbide cuts so fast on brass you only need a single turn or one full revolution.
For trimming your brass have your gunsmith run your reamer into a piece of old barrel about 1/4 inch past the shoulder.
Now go to your local hardware store and buy a 3/8 end mill and a shaft collar.
Put a piece of brass into the barrel stub after full length sizing it and adjust the shaft collar until you get the length correct and lock down the set screw.
For trimming your brass have your gunsmith run your reamer into a piece of old barrel about 1/4 inch past the shoulder.
Now go to your local hardware store and buy a 3/8 end mill and a shaft collar.
Put a piece of brass into the barrel stub after full length sizing it and adjust the shaft collar until you get the length correct and lock down the set screw.

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