John Knibbs gas-ram kits...

[Hellequin]

Just a quick one to ask if anyone has any views/experience of the aftermarket gas-ram conversion kits by John Knibbs?

I have an old (ish) springer which I'm thinking about using as a conversion experiment but it'd be handy to hear any reviews, good or bad, before I go for it...

Cheers

[gunsnlandies]

I've fitted rams into few things, as I like rams. Depending on what you want to fit it too, Protek does the Crosman ram for £25 but you will need to spin up your own adapters. Whatever ram you use, the body needs to fit inside the length of the piston when cocked, otherwise the piston won't engage the sear. IMO Knibbs is expensive for what they are, but then it's your money. Sorry I can't help on the Knibbs kit.

[Hellequin]

I've fitted rams into few things, as I like rams. Depending on what you want to fit it too, Protek does the Crosman ram for £25 but you will need to spin up your own adapters. Whatever ram you use, the body needs to fit inside the length of the piston when cocked, otherwise the piston won't engage the sear. IMO Knibbs is expensive for what they are, but then it's your money. Sorry I can't help on the Knibbs kit.

No worries mate, the advice is appreciated anyway! The rifle is a Brum built BSA Supersport in .22 calibre. I have a carbine version too but want to keep that one with a spring in it, unless I try the gas-ram and absolutely love it...

[bighit]

Hatsan do an adjustable one but that's not to say it will fit your rifle . possibly get adaptors made . The problem is the adjusting . It has to be done with the ram outside the gun . If you put it in and its 8 ft lbs .You need to remove it and pump it up then try again . If its then 13 ft lbs you have to strip it and remove air .
https://sharg.pl/product-pol-103612-...TYPE-1-ST.html

The AWT/Theoben .I had one in my AIR ARMS Hi-Power . Fitted it my self and they are non adjustable . I had to fit it my way to get the power up . They said to leave the spring guide 4mm but I left mine long for fine tuning .I adjusted the length till I got the power I wanted .

The Gamo one for your BSA is the same as the AWT/Theoben in design . They cant be be adjusted hence why I did the th fine tuning route

It was fine to shoot . I traded it not long after as my hobbies changed .

There are other gas rams made throughout the world as seen here


https://airenlaces.blogspot.co.uk/20...iston-igt.html

[Hellequin]

Hatsan do an adjustable one but that's not to say it will fit your rifle . possibly get adaptors made . The problem is the adjusting . It has to be done with the ram outside the gun . If you put it in and its 8 ft lbs .You need to remove it and pump it up then try again . If its then 13 ft lbs you have to strip it and remove air .
https://sharg.pl/product-pol-103612-...TYPE-1-ST.html

The AWT/Theoben .I had one in my AIR ARMS Hi-Power . Fitted it my self and they are non adjustable . I had to fit it my way to get the power up . They said to leave the spring guide 4mm but I left mine long for fine tuning .I adjusted the length till I got the power I wanted .

The Gamo one for your BSA is the same as the AWT/Theoben in design . They cant be be adjusted hence why I did the th fine tuning route

It was fine to shoot . I traded it not long after as my hobbies changed .

There are other gas rams made throughout the world as seen here


https://airenlaces.blogspot.co.uk/20...iston-igt.html

Blimey...!

I thought it'd just be a case of removing old internals & doing a bit of clean, then fitting the specific gas-ram for the Supersport. To be honest, for something I'm not sure I'll even like, I'll probably stick with a spring!

I've found that BAR still (according to their website) have some stock of Theoben rams to fit various rifles but I'm not sure if they differ to the one which Knibbs' sells or not.

[bighit]

Blimey...!

I thought it'd just be a case of removing old internals & doing a bit of clean, then fitting the specific gas-ram for the Supersport. To be honest, for something I'm not sure I'll even like, I'll probably stick with a spring!

I've found that BAR still (according to their website) have some stock of Theoben rams to fit various rifles but I'm not sure if they differ to the one which Knibbs' sells or not.

The Theoben/ AWT one was a modify the end block to fit the ram. but that may have depended on the rifle and how it was made . The newer gamo ones will be different . they should be as you say a drop in kit as they were designed at the time of making the rifle where as the Theoben/AWT was a retrofit.

An old post about one in a BSA superstar

http://www.airgunbbs.com/showthread....-few-questions

The way it was set up to me looks like the rifle was low on power and the person made the threaded adjust setup to fine tune it .

If you go for a Gamo one you may need a few parts to fit it as they say in the page
BSA GRT Gas Ram

Fits
GRT Lightning SE
GRT Lightning XL SE
GRT Supersport SE
Lightning XL SE (Requires part No.36540)
Ram Width 19mm
Ram Length 217mm
Ram Seating Washer Width 23mm


If you go for a Gamo one it will be spring out and gas ram in .

[look no hands]

Blimey...!

I thought it'd just be a case of removing old internals & doing a bit of clean, then fitting the specific gas-ram for the Supersport. To be honest, for something I'm not sure I'll even like, I'll probably stick with a spring!

I've found that BAR still (according to their website) have some stock of Theoben rams to fit various rifles but I'm not sure if they differ to the one which Knibbs' sells or not.

I'd stick with a spring if I was you, I had a couple of the Theoben drop in rams in my BSA's and they both leaked, the trouble is they are sealed units and can't be adjusted, so if it's 8ftp or 13ftp you can't do nothing about it.

Pete

[Hellequin]

The Theoben/ AWT one was a modify the end block to fit the ram. but that may have depended on the rifle and how it was made . The newer gamo ones will be different . they should be as you say a drop in kit as they were designed at the time of making the rifle where as the Theoben/AWT was a retrofit.

An old post about one in a BSA superstar

http://www.airgunbbs.com/showthread....-few-questions

If you go for a Gamo one you may need a few parts to fit it as they say in the page
BSA GRT Gas Ram

Fits
GRT Lightning SE
GRT Lightning XL SE
GRT Supersport SE
Lightning XL SE (Requires part No.36540)
Ram Width 19mm
Ram Length 217mm
Ram Seating Washer Width 23mm


If you go for a Gamo one it will be spring out and gas ram in .

Not sure if my SS is the same (as the XL/SE) as it's an older model from around 1995/6, although I'm guessing the internal dimensions haven't changed much over the years.

Thank you very much for the info.

[bighit]

I'd stick with a spring if I was you, I had a couple of the Theoben drop in rams in my BSA's and they both leaked, the trouble is they are sealed units and can't be adjusted, so if it's 8ftp or 13ftp you can't do nothing about it.

Pete

http://www.airgunbbs.com/showthread....-few-questions

Ben Taylor says that's how it was done at the time in the post above . could the threaded part be an adjuster?

when fitting my AWT/theoben one I left the spring guide longer than the instructions said to fine tune . I cant remember now if it was the size theoben said or less by the time I got it so it was not loose in the rifle and it was cocking properly.

It was 20+ years ago

[bighit]

Not sure if my SS is the same (as the XL/SE) as it's an older model from around 1995/6, although I'm guessing the internal dimensions haven't changed much over the years.

Thank you very much for the info.

chambers pic here


Its like the setup from the superstar post .


you could ask Knibbs if the Ram he sells fits yours

[Hellequin]

I'd stick with a spring if I was you, I had a couple of the Theoben drop in rams in my BSA's and they both leaked, the trouble is they are sealed units and can't be adjusted, so if it's 8ftp or 13ftp you can't do nothing about it.

Pete

Yep, I reckon you're right Pete. It was just a thought as I saw the kits whilst looking for servicing spares on JK & Chambers sites... It was one of those 'ooh, I wonder what that'd be like' moments but figured I'd get some real world advice here first.

[bighit]

I know its a different rifle ,Im sure Thisisdonald was fitting one to a webley vulcan not long back. Not sure if he did get it done though .

[Aa410k]

I’ve got an old bsa supersport with a John knibbs gas ram in, it 10.5ftlb consistently and it’s an absolute dream to shoot. I fitted it in January and put about 2000 pellets through it. I love it! Much nicer then spring twang, a nice thud.

[EdSIII]

I put one in a .177 Tracker last fall and it made the gun a much nicer shooter, no twang and a nice quick lock time, shooting just under 10ftlb

[Hellequin]

I’ve got an old bsa supersport with a John knibbs gas ram in, it 10.5ftlb consistently and it’s an absolute dream to shoot. I fitted it in January and put about 2000 pellets through it. I love it! Much nicer then spring twang, a nice thud.

That sounds good, was it a straight 'drop in' and go or did it need adjustment/fine tuning?

Cheers for all the replies gents, much appreciated!