BNM O rings

[Seatec]

What is the size of the O ring that fits over the end of the barrel  where the transfor port is.
I had to take mine apart a few times for a jamed pellet. The hole in the barrel for the transfer port had a sharp edge, so I fixed that and did not hurt it the next time I had to take it out.
Is there an easy way to clear a jamed pellet, other than taking it all apart.
Can I just use a regular O ring if I can find the right size.

Wayne

[ped]

I just use a cleaning rod in situ -removing probe lug and probe then rodding from the rear if no shroud is fitted -if one is I would take it off first or you'll have a pellet rattling in the baffles
o ring is a bs111

[Seatec]

I guess there is no short cut, without taking it apart.