Taipan Veteran Leak Help

I need some input from those that are more knowledgeable then I on the Taipan Veteran system, in regards to a leak I've encountered. 

In the quest for more speed and power, I want to push the .22 RD monsters faster, I've done some modifications to my .22 Taipan Veteran Long. I've added a power plenum, replaced the stock regulator with a Huma regulator, and I've ported and polished the transfer port per Ernest Rowe's instruction on youtube. Upon assembling the rifle, I've encountered a leak in a spot that I can't quite figure out. 

The airgun is leaking from the hole where the grub screw goes to retain the transfer port, and I can't make sense of it. I've since taken it apart and reassembled it a few times, perhaps it wasn't quite assembled properly, with no change in success. 

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"I've ported and polished the transfer port per Ernest Rowe's instruction on youtube. Upon assembling the rifle, I've encountered a leak in a spot that I can't quite figure out. "

is there an o-ring on the transfer piece you polished, you are leaking around it

There is, there's an o-ring that sits on the front face of the transfer port, which was installed. After taking it apart a couple of times, I decided to put some silicon oil on the o-ring to see if that helped with the leak, to no avail. 
 
Okay, I think I may have found the culprit. There's an area on the sealing face of the transfer port that looks like there's been some flow by. If you look just above the red arrow, you can see evidence of some gas flow. 

So I'm assuming this leaves me with two options: 1. Find a machinist to machine that face perfectly flat. 2. Get a new transfer port. Am I right in those assumptions?



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does not need to perfectly flat---just smooth and sealable, o-rings will conform, I would just polish it,, a fine scotch brite pad and a drill, if you chuck it up in a drill or drill press. I have even used the cloth side(back side) of emery cloth for a fine finish. And if you have a spare o-ring, I would change it for a new one

If you machine it, you will change the lenght, will that cause a different problem?
 
Does it still leak if you completely remove the hammer and spring?

I'd bang it with a rubber mallet real hard many times and see if that helps after removing the hammer and spring.


Sorry, what exactly are you suggesting needs a good whack with a rubber mallet?

I did not remove the hammer and spring, I could try that to see if that helps.

I suggest whacking it with a rubber mallet in case it was minor and there was only dust or debris between the valve seat.

Lots of fixes don't require disassembly believe it or not regarding leaks. Just a good old fashioned whacking is all it takes.