Howdy Rufcut'
It sounds like all your chains are 3/8 pitch, the McCulloch one is a branded Oregon. All will require a 7/32" file. That makes it easy. Now see if you can come up with a filing instruction sheet from the local dealer. Often there is one on the back of the chain loop boxes. You need an illustration of a correctly shaped cutter of the type you wish to file. There are two basic types of sawchain around, the ones with a slightly round working corner on the cutters, and the ones that are square, that is to say flat across the top, and intersecting with a flat sideplate, with very little or no radius obvious between the two.
The round corner cutter type is called semichisel, and the square one is chisel. They are filed slightly different. On the semichisel you hold the file level across the chain at a 35 degree angle to the centerline. On the chisel you hold the handle of the file down 10 to 15 degrees, and the angle across the top comes out at 30 degrees. It is easier to make them look right as compared to an illustration, than to worry about how many degrees!
When filing, file with your forearm in a straight line with the file so you stroke with a nice straight pendulum-like stroke, lightly and smoothly. No wiggle. (It is not necessary to rotate the file as you stroke. The spiral of the teeth takes care of the shedding of chips). Keep your file clean and dry, free of oil or dirt. Don't touch the teeth, or the oil off your fingers will cause it to load up and/or rust. Wipe the file off by rotating it in a clean rag if it needs cleanning. (I usually just wipe mine on my jeans!) After three or four filings, you need to reset your depthgauges. That requires a different file guide that is inexpensive. This restores the bite the cutter can take.
Be sure to file your chain before it becomes totally uselessly dull and/or damaged. Sharpening from wood dull condition is easy and only takes a stroke or two. Trying to restore a damaged chain is difficult and if it hit a rock or metal, it may be impossible, as the cutters will be work hardened harder than the file. The secret is to file often and lightly. You get far longer life out of your chain and it is less work.
Regards,
Walt Galer