Is it unheard of for stock VSR cylinders to crack?

[morugatu]

Basically I have looked all over and can't really find anyone else who has cracked their cylinder and I am worried about mine as it has two parallel lines on either side of the cylinder right behind the cylinder head and I am afraid of it cracking?

 

I have used sorbo on both the piston and cylinder head, so I'm a little perplexed as to how these could have formed?

 

My theory is either from adding too much Teflon tape in the threads of the cylinder head, drilling out the cylinder head pin somehow caused this (I've had this for years after doing the drilling, so I doubt it) or being too rough with screwing the cylinder head back on could have done it?

 

I'm just not quite sure if this is no big deal or should I be worried and looking into a new cylinder? I would put up photos, but I have it packed away at the moment for a trip.

 

Thank you!

 

Note: My USR 11 is totally stock. I will be replacing the hop up rubber and putting in a tightbore, but the cylinder is stock. In all honesty, I'm more curious than worried as I plan on running this replica into the dirt since I've had it since it came out and will likely replace it with some other VSR clone and toss any aftermarket parts I have later on into that replica.