Quoted:
That's a good idea. Unfortunately, it never occurred to me to check the gas port in the bottom of the FSB when I had the thing off last night. Do you think that I might be able slightly enlarge the opening there to trap gas in case it is slightly off center? Or, might that be asking for trouble?
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Uh, don't enlarge the gas port unless you want the problem to get worse. This is a typical misunderstanding to the causes of short-stroking. See, the gas system is designed for only one thing: to unlock the bolt from the barrel extension. There is nowhere near enough gas to push the bolt all the way back in the carrier; the force of the cartridge does that after the bolt unlocks.
The timing of the system is so that after ignition, when the forces in the chamber are highest, the bolt is locked into the barrel extension to prevent a kaboom. As the bullet travels down the barrel and passes the gas port, hot gas runs down the tube and unlocks the bolt just when pressures have dropped to safe levels. However, too much gas will have a much higher velocity and will try and unlock the bolt early. This isn't dangerous, but the bolt will try and yank the cartridge out (the cartridge can be exerting several thousand PSI against the chamber walls) and not have enough residual energy to do so by the time pressures drop. With a Bushy this is not so much a problem with regular ammo, but Wolf and other cheap ammo can have slower burning powder. This translates into a higher pressure spike in the barrel just when the bullet passes the gas port. Faster burning powders have earlier pressure spikes, so the Bushy is less prone to short-stroke on them.
All that to say you might have an overly large gas port to begin with. Unfortunately there's no easy way to test this, short of making a smaller hole, or buying an adjustable gas block from JP Enterprises or someone like that and testing it. To get a smaller gas port have a professional gunsmith do it. Or, if you feel confident, just drill out the old one, weld in a bushing, then drill a hole in it that is smaller than the original.
Hope this helps.
ETA: I just thought of this and have no idea if it'll work. First off, are using standard gapped gas rings on your bolt carrier? If you're using the "fancy" one-piece gas rings, switch them back. A lot of people have problems with these because of excessive gas pressures. If that doesn't work or you're already using standard rings, you could try and use a grinding wheel on a rotary tool to widen the gaps. Hopefully this will reduce the gas pressure enough to fix the problem.