Gamo cf20 mod version any information.

[rovercoupe]

I recently bought a sorry looking gamo cf20 and it looks like after a bit of research its a mod version with a odd extension on the end of the gun for a different sight and its a low power model. Does anybody know anything else about them and is it possible to get it up on power or is it stuck at 6lbs.

[Phil Russell]

A CF20 could easily become a 'full power' rifle providing the spring is suitable ... square section monster not needed. Make sure piston washer is OK as well.
Cheers, Phil

[Shed tuner]

Mine was of the same type... my thread about some improvements here:

http://www.airgunbbs.com/showthread....highlight=cf20

[rovercoupe]

How bizarre, had a look down the barrel and sure enough the rifling just ends! Chambers has come up trumps with a new spring and seal arriving today and with excitement I replaced the seal and spring and the power was 6lbs..... Put some pennys in the end and no difference. Maybe its just destined to be a low power rifle. Now do I chop the end or leave it as a original as i wanted a hunter and it looks like its going up for sale once the stocks refinished.

[TonyL]

How bizarre, had a look down the barrel and sure enough the rifling just ends! Chambers has come up trumps with a new spring and seal arriving today and with excitement I replaced the seal and spring and the power was 6lbs..... Put some pennys in the end and no difference. Maybe its just destined to be a low power rifle. Now do I chop the end or leave it as a original as i wanted a hunter and it looks like its going up for sale once the stocks refinished.

Can these suffer breech leaking issues with the pop-up port?

[Phil Russell]

Re breech leak ... I fully expect so. So this could be checked by the wet tissue method.
Also, I have known issues with the breech 'plug' locating properly. It might be worth trying to see if the pellet is moving from loading bay to barrel without hindrance. Maybe by loading and firing into water or whatever to allow the pellet to be examined for scores or tears etc.
Cheers, Phil

[gwyn]

I recently bought a sorry looking gamo cf20 and it looks like after a bit of research its a mod version with a odd extension on the end of the gun for a different sight and its a low power model. Does anybody know anything else about them and is it possible to get it up on power or is it stuck at 6lbs.

Hi , i have one of these ex MOD CF20 Gamos,it was chrono'd at 8ft lb,nice smooth and accurate,at 25yds off a bench rest it would do five shot groups time after time, then the spring broke i took it to a gunsmith and had a new spring and seals fitted,came back returning 9.5 ft lbs but has never matched its old performance,too much power now??
Don.

[rovercoupe]

This is now twice in a week where a simple seal and spring replacement has caused more issues than a full re seal on my pcp! So it should up the power with a new spring and seal but it has remained exactly the same. To be fair the old seal was scored to hell and was still doing 6lbs so there pretty hardy guns!