$9 shrouded barrel for QB78....

[Rob M]

lol, about 12 minutes machining the crosman parts , u have a kit. ( if one wanted to do so

[rewinder]

Well I had to jump on this mod after reading the thread. It's an elegant solution for a semi full shroud.

I started with a qb79 on a co2 9oz tank, and a umarex moderator taped up (15mm barrell)

I goofed of for few hours the last 2 days at work and turned the parts, threaded the adapter on my lathe with a supported die against he tailstock. It want together slick as can be. the only changes I made were to put the rear support set screw outside the tube, and  chamfered the right angle where the baffles meet the adapter about 60 degrees,so the smallest edge of the chamfer ended at about 15mm instead of 3/4" . This i thought would unblock the semicircular slots on the threaded end of the baffle and allow pressure to flow back toward the breech, inside the tube .

No difference in accuracy when I tested it out this evening.

I can say th it is every bit as effective as the umarex unit, and maybe more so. There is a difference in sound, hard to explain it. But it looks so much better than that larger "pickle" sitting out there.

Anyone wondering about tank clearance. I have some old brass eagle all steel tanks and newer aluminum standard paintball tanks, and both fit fine, w/ clearance. the newer aluminum ones are larger diameter than the steel ones.

Going to do the same thing to my 79 on hpa next.

thanks Kevin for posting this great mod, It works as well as you said it would

I could post a pic, but it looks the same as Kevin's, just has a bottle on it
 

[Rob M]

so where did ya get the shroud> i was kinda confused by ur umarex reference?

[rewinder]

I meant the tube from crosman, I called that the shroud. The umarex reference is this:   https://www.pyramydair.com/product/umarex-compensator-fits-hammerli-850-walther-1250-dominator-beretta?a=1135

Much bigger diamter

[Rob M]

sounds good.!!!