The transfer port (35) is the interface between the valve and the barrel on the 22xx series guns. It can be a restrictive item in the flow of CO2 and by changing this for a larger or smaller bore version you can increase or decrease the power.
Standard transfer port sizes in the UK are 2.8mm for the 2240 pistol and 3.6mm for the 2250 and 2260 rifle series.
The standard transfer port (35) sits in a rubber gasket (34) on top of the main tube, this gasket seals between the transfer port and valve. Note there is a short and long edge to the transfer port, the short edge goes in to the seal.
A good way to upgrade the transfer port in the UK is using a design by engineer John Small which does away with the need for the gasket with his design.
The bore on John's transfer ports can be in 4.2mm or 4.5mm and typically sell for around the £5 mark.
They can be purchased on eBay seller ID Josma20, just search eBay for Crosman Transfer Port.
New arrival in the armoury.
Latest custom gun.
New arrival in the armoury.
This is a project I have planned for a long time.
A nice lightweight 2250XL Build.
The Scaramanga "bullet" 2040 Gun is my latest project.
This 2260 has just been assembled with a fantastic one off Geordie stock. Made by master craftsman Mr Gordon Bell. I am looking to add some hardware when I actually see something that will enhance the look.
This is a one off Bullpup made by Bluefork Designs.
This project was built to see how far I could go without using any Crosman parts at all in my build.
DAQ .25 Cal Breech and Barrel + More.
Sam Tussing Breech + More.
This is no Ratty but is a recent project that is undertaken. Based on a .25 Marauder Rifle and using a Spanish Bullpup kit.