What is the name of this part?

[88turbocoupe]

Installed the 380mm barrel on my notos which works very well
Only issue I have is small air leaks from the barrel o rings

I am wondering if it's possible to replace this brass part as this new one has 3 transfer holes vs one

As I see it when the gun fires its also getting a burst of air out if the other 2 holes and putting pressure on the o rings

 

[88turbocoupe]

the brass piece on the bottom in the pic only has one hole maybe i got sent the wrong part or re designed.

 

[Stubbers]

Thimble.

 

[sb327]

In both cases, the orings will see pressure. The one with 3 holes is designed that way to allow the thimble to perform no matter how it is aligned with the transfer port. The one with a single hole requires alignment with the transfer port to function correctly.

Dave

 

[subscriber]

Notice how the three hole version has a groove joining them, for the air to spread circumferentially? As sb327 said, the thimble orientation does not matter with the three hole version.

Another benefit is that the three smaller holes won't allow the projectile to drop into the transfer port hole and scrape. That said, the outer transfer port hole edges on the 3-hole version have some burrs. These don't matter, but if there are burrs at the inside of these TP holes as well, those will scrape the projectile. In which case some careful deburring with a small scraper or needle file is suggested. Not a job for an incoordinate Dremel burr....