Gamo Urban Shroud Conversion

The Gamo Urban is an impressive entry PCP full of features we expect to see on more expensive rifles. The things I particularly like about the rifle is it is light weight, quick to fill from a hand pump and the BSA hammer forged barrel the delivers fantastic accuracy! Mine is doing 860 FPS with 18 gain JSB Exacts out of the box. However, I find that the OEM LDC makes shouldering and maneuvering awkward due to all the added weight and length at the end. Insult to injury, it’s UGLY! I wanted to design a full-length shroud that met the fallowing requirements. 1: Functionally better to the OEM LDC. 2: Aesthetically pleasing. This involved matching the geometry on the slant cut receiver to the shroud. Lastly, compactness. The stock length of the Urban is 42 inches. After the conversion, it measures in at 38 inches. Just this alone makes the Urban feel 2 pounds lighter and easier to navigate through the woods.

I had hoped that Gamo only had epoxied the OEM LDC to the barrel but under further investigation, this was not the case. It turns out that the LDC is molded around grooves in the barrel. The only way the LDC is coming off is by destroying it. I took the LDC apart to measure where the muzzle of the barrel is inside then cut the LDC an inch past the muzzle. Afterwards, the barrel was dialed in my 4 jaw chuck on the lathe to surgically remove the plastic remains from the barrel.

http://cdn.pyramydair.com/images/zoomed/PY-4100_Gamo-Urban-PCP-Air_1476363105.jpg

I had two choices for mounting an air stripper. I either cut the thin portion of the barrel off, turn it down and cut a ½-20 thread concentric to the bore with a new crown, which would lose the choke as a consequence but make the OAL length more compact. Or machine an undersized bushing to press fit over the newly turned down portion of the barrel and thread the bushing concentric to the bore. I chose the latter to preserve the choke. The bushing OD was tuned down to match the barrel OD and then the threaded section was turned down in relationship to the bore. I left the bushing unfinished to illustrate the work.

All DONE!! What an improvement. Not pictured, but the shrouds implements gen 2 marauder style internals but made to tighter tolerances.