Transfer port seal mod

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For the TDR I was struggling with power - hard to get over 9 ft lbs due to the very short barrel  12 inches and in 177 .....
I use this mod for all of my guns now as it aids efficiency.

I wanted to drastically improve how the transfer port worked
The standard way is a piece of tubing cut and squashed between the bottom tube and breech this can work well but often can leak and the tube can get squashed and partially block the flow of air.
There have been a few ways suggested to improve the TP seal this was my solution - sure I am not the first to do it this way, but it does work very well !

with the valve removed I drilled the valve block around halfway down with a 6mm drill



then insert a piece of brass tube into the breach and then solder in place



I then push a short length of nylon tube over the brass tube, this seals very well and cannot be crushed when tightening the breach to bottom tube

When assembled the nylon tubing is compressed  into the counter sink in the breech - the brass tube keeps the transfer port fully oped up - it cannot be crushed!
seems to work very well - absolutely no air leaks and lots of flow !

this is a great aid to consistency as the TP is always the same size.

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