gas ram install..?

[triry]

despite the  drawbacks, im toying with the idea of gas-ramming my son ryans big-cat.  to that end, has anyone installed one themselves ?
any positive feedback regarding a post gas-ram install ?
if so, is there any reference material for the install ?

thanks guys...............jim aka triry

[airiscool]

Jim,
I don't remember mention of a Big Cat, but there've been quite a few posts in the last 6 months about Air Venturi's being installed in Whispers - mine included.  I love it now that it's settling in and I've found using heavier pellets makes a big differance in acuracy.  


Here's one post from CO -AirGunner, might be similar to your Big Cat.
http://www.gatewaytoairguns.com/airguns/forums/thread-view.asp?tid=16773&posts=12&highlight=venturi&highlightmode=1#M136552

A search using "Venturi" tuned up a bunch of others.

Just don't do like I did and assume the factory seal was ok ... it wasn't and the air venturi puts greater strain on it. I'd recommend honing, then put in a good seal and lube from J Marccari while you have it apart.

Hope it helps.

Paul.

[triry]

PAUL,

outstanding info !! this will go along way in my decision.!!

[AKJC1977]

Have not owned one personally,but have shot one.My friend ordered one from Pyramid pre-installed. I had also considered the idea and posted a thread few weeks ago,on Gamo gate. You need to scroll on down til ya find it cause it had bout thirty some replies with a welth of knowledge,from some pro's. It is titled Good and Bad bout Nitrogen pistons. By the way after speaking with Gene before he tuned mY Gamo,Viper .177 I decided not to use gas ram. Just me,not that is a crazy decision or anything.AKJC1977  Thread is on page two

[Evo|ve_S|66]

Hey Jim, if you are absolutely going to get a Gas-Ram install. You might want to consider it to be installed by Pyramyd-Air, being as that they have a warranty on that n' whatnot. And if you "happen" to "mess up"....well then ya know what comes next lol. That being said, I'm not discounting your Airgun tuning skills! Just want you to play in the safe route =] It's a good upgrade from what I hear, however from my recollection....that seal is bound to become a problem soon. So if you are absolutely going to take this route, be sure to stock up on the replacement seals and all that good stuff to "escape" from such peril! Best of luck,

-Jarred

[onechuck]

The gas ram install is very easy with the common Gamo powerplant. I have had many rammed airguns including the Big Cat. There is a very well written guide on the forum that tells exactly how to do the install. The only thing that needs machining is the rear spring guide, and it only requires cutting it down to a shorter length.
link is            http://www.gatewaytoairguns.com/airguns/forums/thread-view.asp?tid=16773&posts=12&highlight=big%20cat%20gas%20ram&highlightmode=1#M136552

If you have any questions, I will try to help in any way I can. I have owned two rammed Whispers .22, two rammed Falcon .22, two rammed Falcon .25, and one rammed Talon .22 along with the rammed Big Cat. As you can see, I am a very big fan of rammed airguns! If you choose to proceed with the enhancement of the Cat, it would be easy to replace the piston seal and lube tune the airgun while the entrails are exposed. I still have two Walther rammed .22 and one rammed Whisper .22 for sale if interested in the classifieds. Be careful with the breakdown, and "ram away"!
On another note, I am about to order a Condor and Evanix Blizzard through Pyramyd Air. Being that I have a dealer account with them, is there any demand for these caliber of rifles if purchased new? I would be able to sell them cheaper than retail, but would not want to get into the whole "retail gun sales" as this is just a hobby of mine.  I am a ER nurse by profession, but I greatly enjoy the art of airgunning. I couldn't sell the cheaper rifles much cheaper than retail, but I have leeway on the more expensive breeds. Thanks for all this board offers, and I hope I've helped with the air ram decision.
MC

[airiscool]

".................The only thing that needs machining is the rear spring guide, and it only requires cutting it down to a shorter length.
................".

That may not be the case with all Gamos.

I bought my Whisper last Febuary and either Gamo changed the design, or some just think the tube is part of the spacer block, but it wasn't  on mine.

Having read  what CO_AirGunner had to do to install his air venturi in his Whisper  I assumed I'd have to do the same. That is,  until I got my Whisper opened up and looked closely at the rear spring guide. It's just a steel tube that is a light press fit into the spacer block. At first glance it looked like I'd have to cut off the tube, but with a bit of light tapping and twisting the tube came right out of the spring spacer block.

Also, I didn't have to machine anything - the spring guide spacer block was the correct length to work with the air venturi just as it came from Pyramid.  I prefer not to cut /machine origianal parts just incase I ever want to re-install the spring.

Paul.

[powhitetrash]

What's the big deal with gas ram?  No really, what are the benefits?

[airiscool]

For target shooting and general plinking - not much.

But,  if you want to use it for hunting like I want to, it can be left cocked, ready to shoot, for long periods without worrying about spring tension loss. Plus, it's less affected by low temperates (hunting season in the North East). And it can shoot heavier pellets without risking spring damage.

Paul.

[onechuck]

Also no spring twang, torque, or worry about how much heavy tar to use when tuning. The ram installation does away with the worry of the tophat, spring, and rear spring guide tuning and lubing.

[triry]

thanks guys,....i think that as more "discretionary" funding comes available......i'll convert ryans big cat to gas ram.!

[mze]

Installed one gas ram in a Gamo CFX and one in a Hatsan mod 70 (Winchester/Daisy 1000 derivatives) on Tuesday and Wednesday.

 Tested both today, Thursday. Both guns are heavier but smoother to cock. Recoil is still there but quicker and is linear without any torque effect. Just a solid "thunk", no twang, no rattle, no crap. The rams installed give MV of ±850fps. Accuracy is very good.

  These rams have been custom made and are not of Air Venturi or Theoben origin.  Installation is very easy BUT you need a very good and stable compressor. 3-4mm pre-compression is required.

  Tuning cannot be simpler. Debur. Get the compression chamber in good condition by degreasing, cleaning and honing. Apply Moly Paste thinly to entire receiver. Replace seal if stuffed. Apply Moly Paste to piston behind seal and where machined at the other end.  Carefully shove piston in, put gas ram in, compress and install retaining pin. Finish assembly. Shoot and enjoy the difference.

  The gas ram will outlast the rifle.

  "The standard durability test for Gas Rams is 45,000 cycles at 20 degrees C and we offer a one-year guarantee against problems caused by bad workmanship or faulty materials".

  How many air rifles will ever see 45,000 pellets shot through them?

  The gun can be left cocked for any period of time without the gas ram losing performance.

Stacking a gas ram against a spring after 6 months will only have one winner - the gas ram!  All you will ever have to do is replace the piston seal when it wears out. How many pellets? 20,000? i don't know how long the seal will last.

  Does this not sound like a very viable proposition?

[mze]

Installed a second ram in a CFX today. Friday 25th. Chronied just under 800fps. Installed a third ram in a Gamo hunter 440 fitted with a 5.0mm barrel.

Here are pertinent comments from the owner of the Hunter:

I just spent a very delightfull afternoon with Vincent (Mze) and Darius (Boomslang) testing gasrams. Here's my findings:

First we fitted a Gasram to Darius's CFX Royal, complimented by the now obligatory VT-1 trigger. The rifle is totally transformed. It shoots at around 750ft/s with AA Fields but the speed kept climbing on the chrony as the whole system is bedding in. It will probably settle at around 770-780 which is perfect. The rifle is super smooth, no comparison to any standard CFX.

Then we fitted a ram to my Gamo Realtree .20 and WOW. After an initial brainfart from me forgetting a spacer in the piston ensuring the rifle couldn't be cocked, we got it right and off to the Chrony. Running 760ft/s with H&N FTT's. That is 15 fpe, and was exactly the power that I wanted for the rifle. The firing cycle is astoundingly smooth. It has the same sharp short jab as the HW90, but being 15 fpe vs the HW90's 18 fpe, means the recoil is almost non-existent.

This is a very worthwhile mod to any Gamo and for that matter to any spring gun. Accuracy of the Camo Gamo was good, but now it has the power and the accuracy. I hit a target with a 16mm reducer at 30m with the first shot after chrony testing.

Well done Vincent.

[mze]

These are further comments by Ou Van, the owner of the Gamo Hunter 5.0, and a recogised air gun owner and tuner of note.

  ".....after Vincent left I shot a 10 shot string on the .20 Gamo. I got an extreme spread of 4 ft/s. Not bad at all. I 'll do some more testing, or leave it up to Vincent maybe?

  ...... it simply means that during the 10 shot string the highest recorded speed was 763ft/s and the lowest was 759ft/s.

  Oh, and of course, I almost forgot the best part. ABSOLUTELY NO TWANG!!"

[mze]

Be aware that springer type air-rifles lose muzzle velocity the higher the altitude. Muzzle velocity at sea level can be 845fps dropping to ±720 to 750fps at 6000'. Installing a gas ram has many advantages but if shooting at high altitudes, one must weigh up the increased cocking effort against the perceived advantages of the ram. My customers, experiencing the reduced velocity at 6000' here in Johannesburg, are adamant the they will never again rely on spring to power their air guns.

Vincent