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Can a gas ram be improved


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#1 MarkHolding

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Posted 17 February 2017 - 02:48 PM

I have a Gamo Whisper IGT and it is shooting at an average energy of 9.4 ft/lbs energy. It has been like this since new about a year ago. Will shimming the gas ram, as with a normal spring add extra power, or does the gas ram pressure remain constant even if shimmed. I have been told that the HW90 could be adjusted by a valve at the rear of the ram and a special pump. I haven't had the rifle apart yet, but wondered if anyone had fine tuned their gas ram. My goal would be 11 ft/lbs, so not much extra energy required, possibly 50 or 60 feet per second.

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Edited by MarkHolding, 17 February 2017 - 02:49 PM.


#2 rapid slayer

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Posted 18 February 2017 - 06:39 AM

you should have taken it back when you first chronographed it.
you'll now need a pump.

#3 MarkHolding

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Posted 18 February 2017 - 01:12 PM

Getting a pumps no problem, I just wondered if the Gamo gas rams were adjustable. I will have to take it out and have a look to see if the gamo rams are designed to be adjusted or not, as you never see many comments on this. If this is the case I will record my procedures and share for anyone else that has a Gamo gas ram. I realise that the Theoben rams are adjustable, but are other brands??????? Thanks for your imput rapid slayer



#4 MarkHolding

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Posted 25 February 2017 - 05:00 PM

I phoned Countryman of Derby, who told me to take it back. They are returning it to BSA/GAMO for a replacement ram, as it still has 2 months on the warranty.


Edited by MarkHolding, 25 February 2017 - 05:01 PM.


#5 DaveL

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Posted 25 February 2017 - 07:26 PM

There's no need for a separate pump if you have either a manual pump or a pressure bottle.  Just an adapter and a LOT of care to ensure you don't put too much pressure into the ram, if the ram's adjustable.

 

I have a Fenman and it was my favourite shooting rifle - when I could still shoot; Ahem! - It used to lose just a wee bit of pressure over a long period and with a bottle, I've topped it up a couple or three times over the years.  It must be pretty low now and I really should flog off some of my guns as they have had no use for some years.



#6 MarkHolding

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Posted 04 March 2017 - 04:52 PM

Just an update to say that I got my rifle back from The Countryman gunshop in Derby within a week of sending it back to BSA in Birmingham. It's all been looked after at the factory, with even parts added that I didn't send it in for, so quite a good customer service from GAMO/BSA. I haven't tested it yet, due to the -excrement-ty weather, but hopefully it is now doing what it should have done in the first place. It had about 2 months of warranty left.

 

 

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#7 rapid slayer

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Posted 08 March 2017 - 07:32 AM

nice one,glad you got it sorted

#8 MarkHolding

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Posted 26 March 2017 - 09:47 PM

Here are the results of the replacement gas ram and seal fitted by BSA. A bit better, but no where near what it should be.
 
https://youtu.be/xAvM4dWr4bE



#9 Jon

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Posted 27 March 2017 - 09:44 PM

Whats it like with non heavy, power usually rises and would be too close a call.

 

Try chrono in a different light may see a good 100ft/sec drop or an increase, common in uncontrolled environments.

No led type chrono is immune to it certainly the Caldwell having briefly had the IR giving wildly random results in controlled lighting to not registering at all.

What im saying is dont take the chrono reading as being correct.






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