What's going on with this MS250 chain?

[JeffRH]

Link to video here:

I have a Stihl MS250 and I'm not sure what's going on with the chain. Specifically, I have 2 stihl chains that have a 2 stamped on the depth gauge and a 6 on the drive link. I also have 3 generic chains I got last summer with a 6 on the drive link.

According to Stihl, those are both compatible with the saw (.325" and 3/8" pitch), but I'm having a problem with the .325 pitch chains when they're on the saw. In the video I linked here, I have one of those on the saw and was trying to sharpen it. I had the tension set to what I would normally have it and the bar nuts were not overly tight. As soon as I put the cover on though, the chain acts like it's stuck on something and I can barely advance it forward with my fingers while sharpening (yes, I'm sure the brake was not on...I checked....several times). In the video it's just sitting on my bench and not in the vice, so it's clearly something in/on the saw causing it. I figure with it sticking like that, it can't be good for the saw at working RPMs so I'm hesitant to use them anymore.

Both .325 pitch chains do that, but all three 3/8" pitch chains advance smoothly.

Any ideas?

 

[Justin Taylor]

You can’t switch from 3/8 to .325 you would have to switch the bar and sprocket

 

[JeffRH]

You can’t switch from 3/8 to .325 you would have to switch the bar and sprocket

I'm assuming I can stick with the 3/8 then since it's moving OK with the bar I have on there?

 

[Justin Taylor]

Post a pic of the bar specs and a pic of the drum on the chainsaw