GTA
General Discussion To Gateway To Airguns => Gamo Gate => : AKJC1977 July 26, 2009, 05:01:07 AM
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Hey, Yeah me again, I would really like a professional opinion about the advantages and disadvantages of the nitrogen pistons. I know what ya read about them. They are quiet,less recoil,not temp sensative and so on. but i really want to know the truth about them as I dont hear many ole pro's talking them up much. I have considered installing one in my Gamo and really want to know if its worth the bother. I dont want to if they are not more durable than a spring and consistent in velocity. Any info would be nice. Thanks AKJC
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This is the answer that CDT came up with back when the gas rams came out. I strongly concur with this statement.
The Gas Venturi or gas ram.... In my opinion, I would not buy it. To me
they are not all that would appear although when they are functioning
properly there is an advantage.. that being there is no double recoil
usually and not quite as harsh. But they are harder cocking over the entire
cocking travel and there is usually a loss in velocity. How much depends on
the gun. They are very expensive to replace and longevity has always been
questionable and are not repairable and have a tendency to leak after a
while, even with the Theoben Gas Rams. Theoben was the developer of the Gas
Ram application to air guns and they only back them up 6 months.
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I must disagree. I personally have owned a shadow for 2 years now, and as a springer it was a decent, powerful enough, rifle, capable of doing squirrel size game at 45 yards. The spring got smoother and then it lost velocity, an i mean from 890 fps with 7.9 to 650s... i had to replace the spring anyway so as puzzled as you were, i took the plunge and added the venturi ram. HOLY SH!7!!! The rifle was transformed. The twang is all gone. I mean nothing, just a solid thud and a bit of rear recoil, that is all there is. Is shooting crow mags at 860 fps, cpl at 945 fps and now my favorite kodiaks, at 770fps. The rifle became a much more effective hunter, and a more serious rifle to take to the field. I had it for 4 months now and also added a trigger, and to be honest, even if it failed, i would replace it with another ram. I even got a Nikko stirling 3-10x44 to be able to do some serious long distance shots. I can go thru cans at 120 yards! I would definitely try it. Again, none of these will last forever, so you can try and change back and forth and not break the bank. But Imho it is worth every penny. And the give strings with no more than 4 fps + or - deviation. and i think is because not all pellets of the same type weight exactly the same...
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This is just my 2 cents !
Every now and then anyone can get a bad spring, or a bad piston ! You can replace many spring, perhaps a lifetimes wort for the cost of one piston. Most that I have read find that they loose fps, not gain them.
I have reviewed the Gas Pistons for years, I wanted one, but after careful consideration, and observation, I decided to stay with the spring ! My Gamo 890S is going on 11 years, and will soon be getting a turbo tune, which cost much less than a Gas Piston installation, and is much smoother.
And my Gamo 890S will still shoot through a tomato (HEAVY) can !!! or two soda (light) cans.
Now I know that I believed that the Theoben Gas Strut was the best solution years ago, and they are very expensive to purchase and install, but Theoben's guarantee, (6 months)convinced me that they were not for me !!!
Now I never try to lead anyone into something that is not the very best, like the GRT-III trigger !! They are the very BEST !!! So you pay your money, and let us all know how you make out !
I wish everyone the BEST !!!
Bill
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Gene dislike gas rams because there less tuneing required.."$$$$$"
Sorry Gene couldn't resist...the opening was TO big...
peace to all air gun tuners.............
Pete
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One thing that bewillders me is when they design
a gun from scratch to be a gas ram gun....
Why the hell do they put a piston in then push it with
the gas ram.??....Common sence says to me use
the body of the gas ram as the piston...that way
you eliminate one complete componet....
Pete
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Your just plain Mean Peter....:D :D
Well one thing is certain for sure. Gas rams are just a replacement for a spring. Springer manufacturers designed the spring guns from the ground up designed to utilize springs. The gas ram is only a mere replacement for the spring and there has been no design or development made to build an air gun around the gas ram like they did for the spring.
Just a point to be made..:)
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My friend just received a whisper with the gas ram and I really like it.
Very smooth cocking and the recoil is more managable while trying to hold on target. This alone makes me want to try one in my cfx. My cfx will go from 3'' groups to one hole groups at 35 yards depending on how I hold the gun while shooting. His new whisper groups quite consistantly no matter the hold, so far not as tight as my cfx, but consistant.
The consistancy is what Im after, I go from bipod to free hand and everywhere in between while hunting, and cant always get the same hold on the rifle. The ram seems to be less hold sensitive (my observation only). Anyone else notice this?
If the rams last very long at all I say they might be worth it. I'd take a consistant 3/4" group all the time over one hole only if I can hold the rifle "just right" some of the time.
My question is can I have the cfx converted to a gas ram, and who will do this, how much $$$$?
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GREAT THREAD:) I ALSO WAS WONDERING ABOUT THE AIR VENTURI GAS RAM..I WILL BE WATCHING THIS THREAD CLOSELY..:emoticon:
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Yes CFX's can and are being converted to gas ram powerplant.
I have my Hatsan 60 (.22) converted by one of our local guys here in NZ. It has gained a whole ft/lb extra. If I use the heavier pellets in it, it is much smoother now. Cocking effort is slightly increased but spread over the whole cocking stroke, not just in the last bit.
CFX's respond well to a 650Newton ram, and produce one hole groups at 30 yards.
It costs us $170 NZ to get a ram made and installed.
I highly recommend.......
GS
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Very easy to see both sides of this, - I'm still tempted to pick one up, and probably will. The "interesting" advantage around here is it isn't "temperature sensitive" - and I can tell you springers are.
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Not temp sensitive as such if you leave them lying in the sun.
But they do have the same issues with the temperature and humidity/ pressure of air as any similar piston powerplant.
We had an experience recently with a 4" POI shift on a spring gun shoot, where the temp/pressure/humidity changed mid morning, and the gas ram air rifles were affected just as much. They get asthmatic. cough cough.
still an awesome springer upgrade IMHO.
GS :D
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munkybiz_9881 - 8/12/2009 7:35 PM
My friend just received a whisper with the gas ram and I really like it.
Very smooth cocking and the recoil is more managable while trying to hold on target. This alone makes me want to try one in my cfx. My cfx will go from 3'' groups to one hole groups at 35 yards depending on how I hold the gun while shooting. His new whisper groups quite consistantly no matter the hold, so far not as tight as my cfx, but consistant.
The consistancy is what Im after, I go from bipod to free hand and everywhere in between while hunting, and cant always get the same hold on the rifle. The ram seems to be less hold sensitive (my observation only). Anyone else notice this?
If the rams last very long at all I say they might be worth it. I'd take a consistant 3/4" group all the time over one hole only if I can hold the rifle "just right" some of the time.
My question is can I have the cfx converted to a gas ram, and who will do this, how much $$$$?
I just yesterday received my .22 caliber CFX with the Air Venturi gas ram installed, as the original spring snapped.
Its muzzle velocity is about the same as with the original spring, but I agree that the cocking effort feels different, although it seems about the same as with the spring.
Instead of getting progressively stiffer until the spring latches at the end, it is full resistance, with no change throughout the cycle.
I don't really consider that an issue, but then, I am no small fry (6'4"/240lbs).
The recoil impulse is a surprise, as it is brisk, without that familiar torque and faint rattle of the spring.
The accuracy is every bit as good as before, which is to say very good.
I can still print .25-.40" groups, depending on the pellet, with the JSB Exact Jumbo taking top honors.
Another very real advantage of the gas ram over the spring that I have yet to hear anyone else mention, is that - unlike with springs - the gas ram can fire any pellet you want to feed your gun, with no fear of damaging it.
This means you can launch even the super-heavyweight Eun Jins and not worry about flattening the coils of a fragile spring.
That would sure make decking larger animals easier!
Another huge advantage, although better known, should not go unmentioned, which is that a gas ram can be left cocked indefinitely, with no fear of damage.
Another plus when out hunting, as people don't usually find say a nasty old Starling sitting up in a tree who will sit long enough for the hunter to cock, load, then perforate him.
In answer to your question, you can get this same conversion by PyramydAir, who charges $110 for the ram itself, but they will install it at NO CHARGE.
I sent mine in two weeks ago, paying UPS $25 to ship and pack it.
I probably could have knocked off nearly half of that price if I had packed it myself, but I have no suitable boxes for a rifle.
PA charges only the shipping charge for the gas ram itself, which is less than $10.
Oh, you should also know that PA has some discount coupon codes out there, one of which I used by hopping on to http://www.retailmenot.com
Just feed that site the URL for pyramydair.com and it will kick back a code good for 10% off.
That allowed me to get the whole thing for less than $110 total!
Not a bad price at all.
Good luck!
Now, *I* have a problem of my own.
Since having that gas ram installed in my own CFX, I have discovered some pretty rapid scope skid.
Since both rings - B-Square two piece with four screws per ring and integral vertical recoil stop pins, both of which are engaged - are not moving, but only the scope is slicking inexorably rearward, I am unsure how to put a stop to this.
The scope has slid well over an inch rearward, after having fired only about 100 pellets through the gas ram CFX it is mounted to.
Does anyone have any suggestions how to put a stop to that slide?
The rings' clamp screws are already tightened all the way down, so it looks as if I will need to use something within the ring clamps themselves to create enough friction to put a halt to the skid.
Anyone? Anyone?
Bueller? Bueller?
Thanks
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Crosman Nitro Piston Air Rifles
Crossman have licensed a gas piston technology and will be incorporating it into a range of air rifles. The word “gas piston†probably has you thinking of gas operated autoloader rifles. In the context of air guns, “gas piston†refers to the piston system of break barrel air guns. Instead of compressing a spring when cocked, they compress gas. When the trigger is pulled the piston is released, the piston is pushed forward by the expanding gas. The piston in turn compresses air which pushes the pellet out of the rifle.
From the press release:
The heart of gas piston technology is its use of nitrogen as the power, instead of a coiled steel spring.
Unlike steel and CO2, nitrogen isn’t adversely affected by temperature. In addition, the technology allows for much easier cocking. The nitro piston starts engaging the moment the shooter starts cocking the gun. Gas pistons can also be left cocked for long periods of time without degrading and losing velocity, the way steel springs do. Also, when a steel spring uncoils, the vibration is not only annoying, it compromises precision. “Nitro Piston technology solves both by creating a smoother cocking force and releasing the gun’s power more quickly,†said D’Arcy.
Images Zoomed Nitro Els122 Zm
Images Zoomed Nitro Piston Camo Zm
The new rifles will not be available until June, but Pyramyd Air have them available for pre-order. They claim the piston system produces a lot less noise (most of the noise from a break barrel airgun is the piston), less recoil, easier cocking and long lasting.
They are available for pre order for $324.99. They comes in .22 and .177 versions (1000 fp/s and 1200 fp/s respectively) and either either a black synthetic or digital camo thumbhole stock. They all feature a bull barrel and two stage trigger.
Air gun expert and blogger Tom Gaylord was involved in the development of the system. If he was involved it must be good! I don’t think he would risk his reputation on an inferior produc
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Yep!
I saw the links over on PyramydAir.
I believe these new Crosman rifles are made here in the good old U.S.A., too!
No offense to you Canadians, Europeans, Aussies, and Kiwis.
:D
You are also right that Tom Gaylord having input for this new rifle cannot be a bad thing at all.
Witness the resounding success of the Crosman Discovery, a rifle that Crosman heavily consulted him about before even putting it up for R&D.
I am happy with both of my CFXs for now, but I would probably grab that Nitro if one of them broke down completely...either that, or go for the gold and get the Discovery!
:)
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No we are on the same page when we are discussing "gas ram" technology.
The Theoben world wide patent protection has expired.
The Theoben agent in NZ has been manufacturing these and installing them for a fair while now. I have two that have been converted so far and another planned.
Sort of speaking from a position of experience. ........
Interesting comment earlier on the use of various pellet weights with gas rams. Yes I agree, as I have used the heavy Eun Jin's 28.5 gr, and also the Piledriver 30gr pellets. They really do pack a punch at range with no possible adverse effects on the power plant. The rifle still shoots sweet when launching a 30grainer!
Cheers
GS
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I have a Gamo Whisper VH with a Air Venturi Gas Ram install by PA. I have had it for about 3 months I guess and it has been nothing but trouble. First it trashed the Gamo scope that came with it. No big loss there I figger. Next it trashed a Leapers 3-9X40AO, knocked a bunch of duff loose inside. Don't know what that stuff was, it was stuck to the inside of the back lens. Leapers was good about replacing the scope, except they sent me a scope mount for a M-16 instead of my scope. They got it right the second time though. Any way back to the whisper. My scope stop setscrew egged out the hole a little. I ended up taking that setscrew out, its a 10-32 thread and retapped it to a 1/4 - 20. You can get any size setscrew at about any good hardware store. That stopped the scope base from moving. I have a Leapers Accutrac one piece scope mount on it now. Now I find out my scope is moving inside the rings and they have the tape inside to prevent that sort of thing from happening. I just sent the whisper to Gene, he is going to take the gas ram out and put a new spring back in. My whisper has a synthetic stock and I think the recoil is just too much for it. Maybe if you have a wood stock it could handle the recoil a little better. I was always getting 2 or 3 flyers after putting 2 pellets in the same hole. The flyers were off 2 to 3" scattered all over. Some say even the power varys from ram to ram. What good is it if it isn't consistant?
Chas
Springers I currently own: RWS Diana 34, .177, Gamo Whisper Deluxe, .177, G RT- III trigger, Turbo Tuned by Gene and arriving soon on a slow,slow boat from Germany a Beeman R-9, .20 cal
Your not lost if you don't care where you are.
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Agree with you, a bad install can cause problems. I tested three different power rams before settling on a 650N ram. 600 N was oh so sweet and gentle +accurate. 650N was perfect for power/accuracy compromise, and a 700N was shaking the whole rifle to bits.....screws coming undone, scope shift etc etc. Although I have never lost a scope yet to damage.
It is part of an intelligent install to sort this out before on selling to the final owner. That is where problems can occur. A smart installer knows the model being converted, and can advise on the correct power ram to install. Just something to consider if people are investigating getting one installed. There is not a "one size fits all" gas ram, and it is a technological principle, not just one product.
I also agree with the wooden stock being a calming influence on the recoil/jerk of the abrupt ram stroke. Mine are all walnut stock'd air rifles.
cheers
GS
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PA didn't give me that option, that there were different power levels of the gas rams. Maybe the Air Venturi only comes in one power. I am thinkin that the gas rams are a point in the right direction in the development of a different power supply. The only thing is there is just one power level that I am aware of. Now if I could adjust the power level and match it to the air rifle its to be installed in, that could be a good thing. Better yet lets have a power adjustment screw on the action we can fine tune it with.
Chas
Springers I currently own: RWS Diana 34, .177, Gamo Whisper Deluxe, .177, GRT- III trigger, Turbo Tuned by Gene and arriving soon on a slow,slow boat from Germany a Beeman R-9, .20 cal
Your not lost if you don't care where you are.
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I put an Air venturi in my Whisper .22
The Gamo scope quit long before I did the swap, so I can't blame that on the air venturi. So did a couple of other "non-springer rated' scopes I tried. The Leapers Mini Swat I have on it now has held up fine.
The 30 mm Leapers one-piece mount I put on egged the stop pin hole and cracked the end of the 10-32 pin that came in the mount. I drilled out, re-threaded, and installed a 1/4-20 bolt in the scope mount with the bolt shoulder, not threaded part, into the 1/4 inch hole in the reciver. Now, the pin fits the hole nice and snug and it's fine.
Acuracy was still variable, but that was traced to a blown seal which had started long before I installed the air venturi. The increased power of the air venturi only degraded the bad seal faster. I put in a new seal and acuracy is back.
Does it have more power now? A big YES ! But since I plan on using it for critters not paper that's a plus for me. And, I don't have to worry about leaving a spring cocked while hunting.
Does it kick more? Yes! But it's a nice, sold 'thunk' and the gun is steadier to shoot than it was with the original spring. The increased kick hasn't affected acuracy.
Is it any louder? After some break-in shooting, not that I can tell from the muzzle noise, and there certainly is less noise from the power plant.
Would I install a gas ram in any other springers I plan to hunt with .... in a heart beat !!!!!!!
Would I do it to a target gun ? No, the gas ram didn't increase acuracy so I see no advantage with a target gun !
And now, Crosman also seems to think sinking alot of money into gas rams is worth doing.
Paul.
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I am very grateful for all the input you guys have gave me on this post, However I still have a feeling it is one of those things where it is your own personal preference. Myself the big thing for me was: Can I shoot whatever weights I want? and Does it last longer or at least as long as a well cared for springer? I think that this technology could be developed to be a lot better than a spring,in the future. But as for now I think it is too close to what its replacing to justify the cost. Just my opinion of course. I would definately try one if I had more springers. But I have only two good springers and one is my sons,So I guess I will just have mine tuned. I plan on buying more guns in the future, as finances allow.AKJC1977
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Good news!
I was having some severe scope skid after I had the Air Venturi gas ram installed in my .22 caliber Gamo CFX, so I finally went with the option that looked the most promising.
I used that tape you see tennis players use to wrap their racquet handles to make them easier to grip.
I have now fired well over 100 pellets of varying weights, from the lightweight H&N Field & Targets through the super-heavyweight Eun Jins.
I see no evidence of skid at all now.
I was able to get it pretty well sighted in through the course of all that shooting, and I will get it dialed in the rest of the way, probably sometime Wednesday.
Should the scope hold still, and the accuracy be as good as I expect it to stay, I will let you folks on here know that this is the way to go with a hard recoiling gas ram conversion rifle.
btw...the tape I used is the "Tourna Grip" brand, available in the sporting goods section of any Wal-Mart, and probably any sporting goods outfit out there.
I'll let you know how it goes.
:)
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Good deal now ya can focus on your groups. Hope it holds up good. AKJC1977
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There are two other solutions to the sharp recoil problem.
Use heavier pellets to provide more of a cushion of air in front of the ram/piston. I found that going from 16 grain pellets up to 18 grain helps, but 30 grain Piledrivers are the best. While the pellet speed is reduced, the action is sweeter so accuracy is enhanced. Getting the cushion of air before the piston head just right is the key......
Shorten the stroke of the ram by spacing in front of it, and shortening the rod accordingly. The speed and momentum that the piston achieves at the end of its stroke is the problem, so shortening the stroke length means it reaches the end of the stroke earlier, is a slower action and is not as violent. Similar if not identical energy is maintained.
GS
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greyskullnz - 8/17/2009 7:37 PM
There are two other solutions to the sharp recoil problem.
Use heavier pellets to provide more of a cushion of air in front of the ram/piston. I found that going from 16 grain pellets up to 18 grain helps, but 30 grain Piledrivers are the best. While the pellet speed is reduced, the action is sweeter so accuracy is enhanced. Getting the cushion of air before the piston head just right is the key......
Shorten the stroke of the ram by spacing in front of it, and shortening the rod accordingly. The speed and momentum that the piston achieves at the end of its stroke is the problem, so shortening the stroke length means it reaches the end of the stroke earlier, is a slower action and is not as violent. Similar if not identical energy is maintained.
GS
I had noticed that some time ago, even before I had the stock spring replaced with the gas ram.
I was surprised when I found that by far, the smoothest shooting pellets were the super-heavyweight Eun Jins.
However, those are probably a bit rough on a spring, but I can shoot those whenever I feel like it with the gas ram.
The only problem is that they drop significantly more than any other pellet, about 2 mils more at 25 yards!
I could foresee using them to dispatch raccoon sized mammals within 15 yards, though, as they really pack a wallop.
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gldprsp - 8/14/2009 2:24 PM
I have a Gamo Whisper VH with a Air Venturi Gas Ram install by PA. I have had it for about 3 months I guess and it has been nothing but trouble. First it trashed the Gamo scope that came with it. No big loss there I figger. Next it trashed a Leapers 3-9X40AO, knocked a bunch of duff loose inside. Don't know what that stuff was, it was stuck to the inside of the back lens. Leapers was good about replacing the scope, except they sent me a scope mount for a M-16 instead of my scope. They got it right the second time though. Any way back to the whisper. My scope stop setscrew egged out the hole a little. I ended up taking that setscrew out, its a 10-32 thread and retapped it to a 1/4 - 20. You can get any size setscrew at about any good hardware store. That stopped the scope base from moving. I have a Leapers Accutrac one piece scope mount on it now. Now I find out my scope is moving inside the rings and they have the tape inside to prevent that sort of thing from happening. I just sent the whisper to Gene, he is going to take the gas ram out and put a new spring back in. My whisper has a synthetic stock and I think the recoil is just too much for it. Maybe if you have a wood stock it could handle the recoil a little better. I was always getting 2 or 3 flyers after putting 2 pellets in the same hole. The flyers were off 2 to 3" scattered all over. Some say even the power varys from ram to ram. What good is it if it isn't consistant?
Chas
I've had an identical experience with my .22 Whisper - after 1500 shots, 3-scopes busted, scopes sliding around, dieseling, 4" flyer shots - just sent it back to Pyramyd. I love the power but the other issues with it have left me with buyers remorse...just picked up a Crosman NPSS. The Crossman doesn't have as much power but a much more consistant and solid feeling.
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Hi Adam,
What ram has been the best in your Mod 55 so far?
600N, 650N or 700N?
Regards
Vincent
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Alex still has the 55 and is using it to test various power rams. Best ask him direct what the best set up is.
I am using the mod 60 currently, and the 650N ram is awesome. No scope problems, but have to use heavy pellets for best result.
cheers
Adam
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The Eun Jin heavies are an acceptable option, as are the Piledrivers. I would think a 21 Grain Barracuda (.22 cal Kodiak) would work very well too.
It basically is still spring piston theory.....just replace the metal spring with a ram. The learned tuning experiences of the past are still valid and can be applied, with a more consistent and less fragile component in place of the spring.
Crosman are on to a winner, and yes power is not everything. The saying that "ya can't kill what ya can't hit" applies to gas rams too. Tuning for the optimum performance is more important than sheer brute force, as always.
cheers
GS
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With all this said, I have heard some really logical opinion's. And it makes me wonder if the nitro series crosman rifle's come from factory with a gas piston? Are they designed around the nitrogen power plant? If so they by all account's should be the best of the gas driven piston gun's.That is just the only one I know of that comes straight from the actual maker with that design. All the Gamo's and others are just modified by a distributor to use gas piston.Those Nitro Crosman's ain't cheap,but I would love to hear opinion from someone who has used one hard for couple year's. Maybe we can expect a gas piston powered gun in the near future with a adjustable valve on it to adjust velocities and accuracy or something really interactive?AKJC1977
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Weihrauch HW90 and various models of Theobens are manufactured with gas ram systems.
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Too true, it will be good to hear all about the model once they have been put to the acid test by the hardest critics around.........airgunning enthusiasts.
Don't we just love to dissect every last model, for all the gossip and debate the pros and cons until the subject matter is exhausted!
Its my opinion that the Crosman model will have been thoroughly researched, developed and tested. It will have been set at sensible power levels for the configuration of the rifle and will most likely be a HUGE success. That can only be good.
If it does prove to be a great model, I forsee gas rams replacing coil springs as a motive power for air rifles in the future. There is much knowledge about coil spring rifles that applies to them also. Put this together with the gas ram technology and we shall see a big leap forward in performance, consistency and reliability.
GS
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Good news!
I tested out my gas ram Gamo CFX, to which I added the "Tourna Grip" tennis racquet grip tape.
I have now put several hundred rounds through this rig, and the accuracy was all that I had hoped (sub 1/2" five shot groups @ 25 yards).
Oh, I also clocked five shots each of all my pellets that I use with the rifle, and the velocity is either right about where it was with the original spring, or just slightly lower.
The consistency of some of the pellets in MV is impressive, especially the H&N Baracuda (also known as the Beeman Kodiak) heavy pellets, which varied only 3fps!
The scope has not moved at all, thanks to the tape, and I see no problems with the scope getting battered to pieces, as some claim their own gas rams did.
FWIW, the scope in question is the Centerpoint 3-9x40 adjustable objective, a VERY good scope for a springer/gas ram.
So, the upshot of this,for anyone thinking about stepping up to a gas ram, is that you might just want to consider getting a roll of the "Tourna Grip" tape at the sporting goods department of your local Wal-Mart, cut two three-inch long strips of it, then carefully (it was a bit tricky getting it in there neatly) clamp the rings over it.
I have now gone form a scope that slid rearward over an inch to one that has not budged even slightly.
Okay, time to go hunting!
:emoticon: