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All Springer/NP/PCP Air Gun Discussion General => Air Gun Gate => Topic started by: pappa on July 23, 2012, 02:08:25 PM

Title: The future of gas pistons???
Post by: pappa on July 23, 2012, 02:08:25 PM
I have 2 nitro piston air rifles that I love and have a lot of respect for. Am also converting one of my good springers to gas piston. In paying attention to new rifles coming out in the last few months, I notice more and more gas piston powered guns appearing. I has crossed my mind that the old springers, as we know it, may be on the way out and gas pistons becoming the new standard. The gas powered pieces offer an edge on technique, usability and maintenance so I'm thinking that this may be a good thing.

A good conversation on this may offer some of us and the suppliers some good ideas. Anyone have an opinion or idea they would like to share?
Title: Re: The future of gas pistons???
Post by: Scotchmo on July 23, 2012, 02:36:43 PM
A well designed and well executed wire spring is going to be more consistent and longer lasting than a gas spring. Because of cost considerations, weight consideration, space limitations and the desire for powerful airguns, compromises are usually made when using a wire spring in an airgun. The easiest way to address those considerations is with a gas spring.

When you want small, light and powerful, the gas spring wins.

Title: Re: The future of gas pistons???
Post by: Willie Malay on July 23, 2012, 03:10:11 PM
Sounds to me like the the topic heading should be: The future of spring guns?
Title: Re: The future of gas pistons???
Post by: ezman604 on July 23, 2012, 03:24:00 PM
It's sometimes good to rehash a topic to bring it to the new members of the forum. But we have discussed this several times in the past. I believe if you search for the topic, you will find many schools of thought. But the consensus is generally that spring power plants are in no danger of becoming extinct. That's just the opinion of many.
NP power plants have been around since I believe the 80's. They continue to evolve and improve. They are a niche of their own, as is the coiled spring. As prices continue to drop and competition stiffer, I'm sure we'll see more and more NP powered airguns. But MHO is the spring will never be 100% replaced.
SAFE & Happy Shooting!!!!
Dave
 8)
Title: Re: The future of gas pistons???
Post by: supertech77 on July 23, 2012, 09:29:08 PM
i am not sure if the spring is in trouble,after the way that browning and or hatsan has come out with the recoil system on the spring break barrel 25 supercharged pistol,its only a matter of time until they use it on there rifles,biggest down fall to spring guns is the recoil and the scope kill,s take that out of the equation ,and with the quality of some of the cheap np out there that company's are putting in these airguns to save a buck,and there is still the temp situation on the np's in winter, i think spring's will be around for a long time,and to me,and imo, tuning the spring guns is 1/2 the attraction to the hobby,so as long as there's us older guys playing, experimenting, and learning and passing it on,spring guns are and will be OK  ; ;D  ;D
Title: Re: The future of gas pistons???
Post by: robert w on July 23, 2012, 09:35:04 PM
seems to me that when i had a benjamin  np , it wasnt very good when you went outdoors in cold weather , i had to let it warm up before any accuracy and power change . 1 of the major reasons im stuck on spring guns . im not against gas pistons . they arent my cup of tea . but it gives lots more options for us to ponder over when buyin another gun
Title: Re: The future of gas pistons???
Post by: cncjerry on July 23, 2012, 10:17:51 PM
without rehashing as someone suggested, as a new member, there is in my experience a huge dfference in recoil with NP winning over spring.  My NP kicks pretty much straight back whereas the spring jumps all over and has noticeable torque.  I would say the NP guns are what, 10% more, if that in dollars?  But I think the real variance is not the NP vs spring but how well the barrel pivots, the trigger and the barrel that would set the guns apart dollar for dollar.

I wish there was a single pump PCP that was powerful and less than $200.  I think that would be the gun to beat.  I was talking to the guy that makes the multi-pump conversions for the IZH pistols.  I was thinking about making a carbine based on one.  Just add a longer barrel with his multi-piump setup but I lost interest and he might have as well since the pumping is a pain.  But I think that is what we need, and accurate, powerful, single pump pnuematic for under $200.  Even if it was bear to pump once, as long as all the parts were strong if I had to stand on it I wouldn't care.  It would also look like a rifle instead of a futuristic weapon like some of the pcp guns.

Jerry
Title: Re: The future of gas pistons???
Post by: yoshi800 on July 23, 2012, 10:42:21 PM
I'm still waiting for a lightweight portable rail gun.  (That doesn't leave me sterile after firing it)
Title: Re: The future of gas pistons???
Post by: cncjerry on July 24, 2012, 01:48:29 AM
one of these days I will find a surplus MRI machine to harvest.  Rail gun would be next.
Title: Re: The future of gas pistons???
Post by: RedFeather on July 24, 2012, 01:53:32 AM
So far, Diana does not have a gas pistoned air gun.  There sales don't seem to be declining.  It's like manual or automatic transmissions.  Both will be around a long time.  One thing to consider is the quality of the gas piston.  You get a bad wound wire spring, it breaks and for about $20 you can get a very well made replacement.  If and when your gas piston goes south, you have to replace the entire piston.  Not a problem today but, twenty years from now, I bet I could still find a spring for a Diana, etc.
Title: Re: The future of gas pistons???
Post by: QVTom on July 24, 2012, 03:07:03 AM
One thing to consider is the quality of the gas piston.  You get a bad wound wire spring, it breaks and for about $20 you can get a very well made replacement.  If and when your gas piston goes south, you have to replace the entire piston.  Not a problem today but, twenty years from now, I bet I could still find a spring for a Diana, etc.

You make an excellent point.   If forward compatibility is important, the spring may be da king.
Title: Re: The future of gas pistons???
Post by: silverback2000 on July 24, 2012, 07:35:34 AM
Back in the days before internet on of the leading airgun mag writers used to hunt with a theoben sirocco always saying how brilliant it was and when I get back into air rifles this year there are gas rams being launched at more affordable prices. Back then I got laughed at for having a pneumatic pump. They weren't real guns. All the Target boys used hw77s and the like even though my gun shot without a wobble. now pcps are the dogs and most shooters I come across use them but the number of springers made and on offer is vastly larger than in the 80s with technological advances at 120 gbp 250 gbp and 350gbp plus. So the market will change but springers are still going to feature strongly for a while longer. Their simplicity tunability and the fact that just need cocking to fire. A screwdriver and basic tools to maintain and tune. Will always be attractive. Why do people run old cars. They like to maintain them. Why do people spend a fortune on modifying cars when the same money could buy the next model up that is already quicker. Because its satisfying to think I tuned that up. Springers for ever.
Title: Re: The future of gas pistons???
Post by: silverback2000 on July 24, 2012, 07:40:11 AM
That was a rant wasn't it? Was it Gamo that claimed big numbers fo
Quote
r a gas ram that didn't deliver? That's gonna hurt gas RAM rep for a year or so.  If your springer didn't deliver the numbers and you like it. Just POP a better spring and seals and the like and go shooting
Title: Re: The future of gas pistons???
Post by: Bullit on July 24, 2012, 09:55:12 AM
Until the quality and consistency of the (standard production low-buck), imported NP is improved, I don't think there's any risk of the spring going away in the near future.  The tuning possibilities up/down is also a plus.
Edited to clarify and eliminate Theoben and high end NP units.
Title: Re: The future of gas pistons???
Post by: D14Jeff on July 24, 2012, 10:06:16 AM
what issues have the nitro piston had ???
Title: Re: The future of gas pistons???
Post by: Kazman on July 24, 2012, 10:30:25 AM
Back in the days before internet on of the leading airgun mag writers used to hunt with a theoben sirocco always saying how brilliant it was and when I get back into air rifles this year there are gas rams being launched at more affordable prices. Back then I got laughed at for having a pneumatic pump. They weren't real guns. All the Target boys used hw77s and the like even though my gun shot without a wobble. now pcps are the dogs and most shooters I come across use them but the number of springers made and on offer is vastly larger than in the 80s with technological advances at 120 gbp 250 gbp and 350gbp plus. So the market will change but springers are still going to feature strongly for a while longer. Their simplicity tunability and the fact that just need cocking to fire. A screwdriver and basic tools to maintain and tune. Will always be attractive. Why do people run old cars. They like to maintain them. Why do people spend a fortune on modifying cars when the same money could buy the next model up that is already quicker. Because its satisfying to think I tuned that up. Springers for ever.
Until the quality and consistency of the NP is improved, I don't think there's any risk of the spring going away in the near future.  The tuning possibilities up/down is also a plus.
Good point . I lived in England back then .
I too had a Theoben Siroco in .22 , also had a BSA Mercury S in .177 ,and a Sheridan Silver streak in .20 . All three are different for sure . My go to gun at that time was the BSA that was until i figured out how to shoot the Theoben .
Hold sensitivty was something i knew nothing about  ( no internet then) . I modified the Sheridan to a really good power level , the Theoben was new technology back then so it was advised to leave well enough alone . As for the BSA , that thing was a power house springer  , easy to maintain and tweak . Yes the years have gone by , but both are still around , while the likes of Diana , Crossman and the other brands are around , i dont see springers dying . No adays i still have a fondness for all rifles . I have a XL1100 , Discovery , Phantom , and Benji classic , plus an array of centerfires , rimfires  , pistols and shotguns , the one i use most though ........... the XL1100 .     
Title: Re: The future of gas pistons???
Post by: Cliff on July 24, 2012, 10:34:41 AM
I recently got an HW90 Theoben.  At 26 Bar pre-charge (377 psi) it's a bloody violent beast. When that gas strut unloads you know it and  so does whatever I'm pointing it at.
It destroyed a Bushnell Trophy XLT in fewer than 200 shots.
I'm going to mount the replacement on a dampa mount and cross my fingers.

I wonder how many times Bushnell will replace the scope before they start asking questions.

Anyway I do like the gas strut.  There is no break in period, It shoots the same right out of the box as it does after a few thousand rounds.  I haven't had it in the cold ( below freezing) yet.  I know that molecules do condense in frigid conditions and seals do get  harder when frozen,  so there may be some kind of net negative in freezing weather as there are with springs and greases. 

There is no reason not to leave the gas strut gun cocked for extended periods since the gun cocked is not under  much more stress than it is when not cocked due to the hefty pre-charge.  Interestingly some engineers will insist that a steel spring, properly heat treated  and made from the correct alloy won't experience fatigue under extended compression.  I know that good springs do fatigue having spent  years as a machinist/tool maker  I've replaced a very great many exhausted and  expensive  springs on die sets.  But they last for many hundreds of thousands of cycles.

I've read the smarmy condescending  write ups about steel springs being  a thing of the past and how some gun makers are stuck with ancient technology (yadda yadda yadda), but  I think that sort of writing merely exemplifies the ignorance of the author. 

I don't think the steel spring is dead.   I think it merely has competition.
Title: Re: The future of gas pistons???
Post by: Bullit on July 24, 2012, 10:47:08 AM
what issues have the nitro piston had ???
Mostly, consistency in power, when new, and longevity due to losses over time.   Same issues cheap auto units have battled.
Title: Re: The future of gas pistons???
Post by: AirScopes on July 24, 2012, 11:01:46 AM
It has crossed my mind that the old springers, as we know it, may be on the way out and gas pistons becoming the new standard.
When a new thing comes along the prediction is often "out with the old"... however it really doesn't work that way. CDs "replaced" records, but records continued to be used by DJs and radio stations. Nuclear power? Solar? Wind? Which G phone do you have?

I know my old guns aren't going anywhere soon, and there are thousands of people like me that own more guns than they need... my guess is that creates a market for springs even in spring guns were to be stopped in production tomorrow.

Man is not a creature who adapts suddenly to change.

Richard
Title: Re: The future of gas pistons???
Post by: Nikoman on July 24, 2012, 03:51:02 PM
I recently got an HW90 Theoben.  At 26 Bar pre-charge (377 psi) it's a bloody violent beast. When that gas strut unloads you know it and  so does whatever I'm pointing it at.
It destroyed a Bushnell Trophy XLT in fewer than 200 shots.
I'm going to mount the replacement on a dampa mount and cross my fingers.

I wonder how many times Bushnell will replace the scope before they start asking questions.
Those Sportsmatch/Dampa mounts should help out a lot, Cliff.
I've said it a few times in other threads that my RX-1 still has the same scope and Dampa mount for over 15 years now. It's been shot tens of thousands of times and there's absolutely NO power loss and NO scope movement. Try shooting that many times with a coiled spring, good luck with that.
When I was shopping for another hunting air rifle, I was looking at the R1 and my wife stepped in, pulled rank and picked the RX-1. She really liked the way the Theoben/Crow Mag shot and thought the RX-1 was a nice partner to that gun, turned out to be a devastating duo in the field.
Cliff, which caliber HW90 do you have?

Another thing I'd like to mention is that my Beeman/Webley Bearcub is out at the moment getting a Gas Ram conversion as we speak. So the coiled spring can kiss my Gas Ram! If there was a gas piston conversion available for my Dianas, they would kiss those coils goodbye. I shoot a lot and most of my guns are for hunting. I got tired of cocking and de-cocking my springers in the field and sometimes I've lost chances because the gun wasn't cocked and ready. Thanks to the gas piston guns, I don't have to worry about that.
I'm not trying to disrespect the coiled springs, they have their place too - like plinking and target shooting for me where they don't sit cocked for periods of time.
My wife and I hands down prefer the way the gas piston guns shoot, much smoother shot cycle and their proven reliability speaks for itself - they've been around for over 30 years now.

And about cold weather, I live in California and it doesn't get very cold where I live. Though the winters can get brisk out here in the valley and a few times I've shot in below freezing (upper 20 degrees F) with the gas pistons and they didn't skip a beat. I Chrony'd them out in the
The only downside I see in a gas piston gun is the cocking effort can be a little tougher but it's never bothered me.
Title: Re: The future of gas pistons???
Post by: QVTom on July 24, 2012, 06:33:40 PM
I recently got an HW90 Theoben.  At 26 Bar pre-charge (377 psi) it's a bloody violent beast. When that gas strut unloads you know it and  so does whatever I'm pointing it at.

Anyway I do like the gas strut.  There is no break in period, It shoots the same right out of the box as it does after a few thousand rounds.  I haven't had it in the cold ( below freezing) yet.  I know that molecules do condense in frigid conditions and seals do get  harder when frozen,  so there may be some kind of net negative in freezing weather as there are with springs and greases. 



Most Theoben owners know this but others may not.

The beauty of the Theoben system is that they do not use a "strut' or "ram" type gas spring cartridge.  The ID of piston is used as the outer cylinder and the rear block where you charge the system is the piston and rod.  Notable advantages are: They are not at the mercy of commercial gas spring manufactures, due to the large Dia. of the piston the operating pressure is considerably lower allowing the user to adjust with  a simple hand pump, fewer parts and under their control.  Very Elegant compared to the "commercial hatchback strut"  Of course this elegance comes a a cost that prevents it use in a $100 gun.

Quote
Interestingly some engineers will insist that a steel spring, properly heat treated  and made from the correct alloy won't experience fatigue under extended compression.  I know that good springs do fatigue having spent  years as a machinist/tool maker  I've replaced a very great many exhausted and  expensive  springs on die sets.  But they last for many hundreds of thousands of cycles.
Basically true for springs with applications the follow "standard good practices"  Springs in AGs are over stressed and  over compressed leading to their short life in relative terms.  Very few spring applications are designed to operate so close to coil bind but we accept this as a necessary compromise of performance, size, weight and useful life.

Tom
 

Title: Re: The future of gas pistons???
Post by: Nikoman on July 24, 2012, 07:00:22 PM
Here's a diagram of the various gas ram, strut, spring etc..
Title: Re: The future of gas pistons???
Post by: CharlieDaTuna on July 24, 2012, 08:30:48 PM
For what it's worth and as I see it, the gas rams are the power plant of the future. They are being improved and perfected more and more as time progresses.

At the same time, I believe the springers will be around for a long time, are dependable and will always have their place, at least well into the future.

CDT
Title: Re: The future of gas pistons???
Post by: cncjerry on July 24, 2012, 08:38:06 PM
here's another one to think about.  What if we put a spring or NP behind a valve.  So you would pre-fire the gun which would use the power of the spring to pump air into the valve, then it would fire again as a PCP.  That would give us all the advantages of both and I don't think it would be that more complex to build. 
Title: Re: The future of gas pistons???
Post by: RedFeather on July 24, 2012, 11:43:46 PM
You would be disappointed in the shot.  Springers (both types) compress the air so rapidly that they generate tremendous, though equally temporary, high temperatures.  This burns off any combustible vapors, adding 100+ fps to the shot.  If you were to compress the air past a valve, it would rapidly cool and lose that added boost.

I think in terms of muzzle loaders when people compare gas piston guns (percussion caps) to wire wound springs (flintlocks).  Go on any muzzle loading forum and you will see plenty of both styles.  To each his own, said the old maid as she kissed the cow.
Title: Re: The future of gas pistons???
Post by: ptpalpha on July 25, 2012, 08:02:56 PM
Does anyone know the reason why Diana doesn't offer any NP rifles? 
Title: Re: The future of gas pistons???
Post by: Cliff on July 25, 2012, 08:13:00 PM
Quote
Cliff, which caliber HW90 do you have?

I got it in .177  I like the faster flight of the .177 over the .22.
Kills everything I point it at.


Title: Re: The future of gas pistons???
Post by: Cliff on July 25, 2012, 08:18:55 PM
Springers (both types) compress the air so rapidly that they generate tremendous, though equally temporary, high temperatures.  This burns off any combustible vapors, adding 100+ fps to the shot.  If you were to compress the air past a valve, it would rapidly cool and lose that added boost

I would very much like to see any hard data based on instrumentation in the air chamber taking the temperature during the firing cycle.  To date all I've seen are people who embrace Gerry Cardew's conclusions.

I have serious doubts  about  the whole dieseling thing.  I have read Gerald Cardew's effort to analyze what was happening when oil was added to the  air chamber and I don't think he had it right.
Title: Re: The future of gas pistons???
Post by: Nikoman on July 25, 2012, 09:00:09 PM
Quote
Cliff, which caliber HW90 do you have?

I got it in .177  I like the faster flight of the .177 over the .22.
Kills everything I point it at.
You are the only human I know that has that gun in .177.
Is the velocity like something in the stratosphere? :o
Daaaaang!
Title: Re: The future of gas pistons???
Post by: robert w on July 25, 2012, 09:14:09 PM
for now i will wait till they perfect nitro pistons . 1 was enough for me . but after a few years they will have it working nicely and then i will pounce on 1 .
Title: Re: The future of gas pistons???
Post by: lillysdad621 on July 25, 2012, 09:32:09 PM
as per the RWS comment... well because they believe in the old adage... ift itz niet skaput, dontz fitzem!!!. i have yet to see an RWS fail. I am 37, my father has an old 34 from the times of Jesus, never resealed, or opened for that matter (til i got into this site... ) and it is the smoothest shooter i have ever had the pleasure to shoot. The spring is a bit crooked, but the seal is intact. It still pushes eleys wasps (yeah, my dad still has like 3 tins left... and wont give them up for anything...) at low 800s all day. I showed my dad a scope for it, made me take it off... asked him if he wanted a tune and a vortek kit, he asked what for. In his words, " it did not needed that stuff then when i taught you how to shoot, and it still don't need it now...". That rifle has defended 3 back yards in my lifetime, and now the flowerbeds in his condo. If i told my old dad that i was to take the spring out of his Diana to fit a shock absorber I would need a proctologist to get it out of my ^&*... if not a good old back hand for disrespecting  "my elders".  Plus there is something visceral about the amount of energy displayed by a thick coil compressing... like in the side lever 48... or the amount of travel that a barrel on a 350 goes thru on it way to cocking its spring... not as obvious as inside a gas ram.
Title: Re: The future of gas pistons???
Post by: Nikoman on July 25, 2012, 09:52:29 PM
Gas rams have been around almost as long as you, lillysdad. I think Theoben came out with them in 1980 so they are a very proven powerplant. The reason RWS doesn't have a system like that is because German companies are very conservative. Take Leica for example, it took them FOREVER to start making digital cameras compared to other companies. When they get into things they spend a lot of time to do it right the first time and a lot of research goes into it. Yeah the springs work fine for them but I see some type of new air or gas spring system in a future Dianawerk rifle. At least they're not like Apple, release something to the public while it's still in the R&D phase and call it version 1.0! ;D ;D
Take a look at HW, all their guns are spring coiled except for the '90 (and they didn't do the gas strut in that).
Title: Re: The future of gas pistons???
Post by: robert w on July 25, 2012, 09:53:37 PM
i second that as a fine old rws diana will last as well as we care for them.
Title: Re: The future of gas pistons???
Post by: pappa on July 26, 2012, 12:02:55 AM
Does anyone know the reason why Diana doesn't offer any NP rifles? 

Diana doesn't make NP rifles because it is not adaptable to their current design. The way a Diana operates is when it is cocked, the spring cylinder has a studded shaft that goes all the way through the back of the spring and into the trigger. The stud sets the trigger and safety and is held by the trigger until the trigger releases it and starts the firing cycle. With an NP piston, there is NO way to get a studded shaft into the rear of the firing chamber to engage the trigger.

This is no problem for most other springer designs such as Crosman because all you have to do to switch over is take the spring and a few other small pieces out, substitute the NP and a few other small pieces and put it back together..
Title: Re: The future of gas pistons???
Post by: RedFeather on July 26, 2012, 12:14:46 AM
IIRC, the Cardews installed a window in the end of the compression tube and visually observed flashes when the gun was fired.  It is also imputed by their experiment wherein they cocked and shot a springer within an envelope filled with nitrogen.  The gun shot about a hundred or so fps slower than when shot using air.  It really makes perfect sense to me.  Compressing that large a volume rapidly would concentrate all of the heat into a tiny slice of the chamber.  One reason why petroleum based lubes shouldn't be used - they provide too much "fuel".
Title: Re: The future of gas pistons???
Post by: pappa on July 26, 2012, 12:21:14 AM
for now i will wait till they perfect nitro pistons . 1 was enough for me . but after a few years they will have it working nicely and then i will pounce on 1 .

I believe that gas pistons are currently about as perfect as they can get. There are specialty manufacturers that make them in all kinds of sizes and powers and grades, including magnums. I own 2 of them that are as good as or better than any springer I have. They are totally reliable and can account for a great number of crows, nutters, possums and raccoons with clean kills. They don't have some of the distracting problems that my springers have such as noisy spring releases and torquing when firing. They are VERY reliable and pleasant rifles to shoot and I wouldn't give them up for anything. I am even in the process of converting a Remington Summit to an NP and am really excited to get it into operation because I know that it will be even better than the spring system that the rifle came with.
Title: Re: The future of gas pistons???
Post by: pappa on July 26, 2012, 12:35:27 AM
To everyone that is using Cardew for an argument against nitrogen or gas springs, you seem to be ignoring a basic design fundamental in the spring and firing chamber design: the gas piston only replaces the spring; the firing chamber does not change and is still filled with plain old air! The piston and seal that you are currently used to in a springer is still there in the same configuration and any combustibility physics that you might want to refer to is identical. The ONLY thing that is changing is the force used to drive the piston and seal forward.
Title: Re: The future of gas pistons???
Post by: pappa on July 26, 2012, 12:49:28 AM
For what it's worth and as I see it, the gas rams are the power plant of the future. They are being improved and perfected more and more as time progresses.

At the same time, I believe the springers will be around for a long time, are dependable and will always have their place, at least well into the future.

CDT

+1

However, I would like to add, here, that I have pondered the problem brought up early in this thread, that gas pistons lose power at low temperatures because cold gasses do not expand with the same force as warmer gasses. As much as I like my NP rifles, I admit that I have never encountered this so I have to bow to it.

I also agree with all those who pointed out that springers will be here for a LOOOOONG time. Partly because of the temperature problem but more importantly, from a cost/maintenance standpoint, they are just easier to deal with.
Title: Re: The future of gas pistons???
Post by: D14Jeff on July 26, 2012, 02:13:43 AM
is there any room for improvement in springs ? better metals/alloys ? better tempering methods ? better winding ratios ? or are metal springs at the peak of with they can do with modern materials and manufacturing process ?
Title: Re: The future of gas pistons???
Post by: lillysdad621 on July 26, 2012, 03:54:45 AM
I agree... but as per being "the future" i doubt it. more like a second option. A spring is simpler to use, as well as cheaper. the replacement is readily available and the average joe can put them in. Lest we forget that its easier to tune a spring rifle... not everyone has a pump to adjust their gas ram pressure, and as of right now (and as far as the 80s) the only adjustable ram is the theoben. The NP fad and the IGT seem more like throwaways than anything. And tuning is not just replacing a ram for a softer or harder ram... when the Theoben style unit becomes more user friendly and tuner friendly, which it has not in 25 years, maybe we will be on our way to " the future".  and when that happens, i am sure my old dad will shake a fist at it from heaven...
Title: Re: The future of gas pistons???
Post by: tjk on July 26, 2012, 12:36:23 PM
Like it  or not, the rams are here to stay. I doubt the "springers" will ever go extinct, but in the long run, production cost of the strut type rams (automated machinery) will be cheaper to build. And as stated before, the ram technology will improve a lot more making them even more dependable and longer lasting. Until then thought, I will stick with my springers and my Theoben designed ram RX1.
Title: Re: The future of gas pistons???
Post by: Bullit on July 26, 2012, 01:15:52 PM
They're made using automation, as much as is possible.  Just minor subassemblies are by hand.  The problem with them, is that the quality won't improve, unless you dedicate a line specifically for this application.  And understand that you don't just unbolt and swap them out, which is current convention.
The cheap imports used are nothing more than factory equipment suspension, static lifts, or uses like the old SUV lifgate units.
I do wish they'd spend a buck on the NPs.
For example: Instead of $70 for a $30 unit...why not $80 for a $40 unit?   $10.00 goes a Long way in Mfg costs.   I'm ALL for them, just wish for a better unit. JMO
Title: Re: The future of gas pistons???
Post by: AirHunter4Ever on July 26, 2012, 03:58:35 PM
On the subject of the THEOBEN Gas Rams, is it possible to buy the Gas Ram assembly by itself for installation into my own air rifles ?

Who sells them ?

Thanks.
Title: Re: The future of gas pistons???
Post by: Nikoman on July 26, 2012, 04:02:01 PM
Yes, but only for certain rifles.

AIR ARMS
sidelevers:
Bora
Camargue
Firepower
Jackal
Khasmin
Mistral

GAMO:
Hunter
Shadow 1000
CFX

BSA:
Goldstar
Lightning
Meteor
Supersport
Superstar

BEEMAN:
Kodiak
R1 (HW80)

WEBLEY:
Eclipse
Excel
Omega
Patriot
Stingray
Tracker
Vulcan
Xocet
Title: Re: The future of gas pistons???
Post by: AirHunter4Ever on July 26, 2012, 04:30:02 PM
Yes, but only for certain rifles.

I am interested in one for a Hatsan 125TH. It has a 120mm stroke length. I know the Webley Patriot is only 114mm.

The one for the Gamo Hunter ( Hunter Extreme ? ) would probably fit if the stroke length is right.  Does anyone know the stroke length on the Gamo Hunter ?

Does anyone know the allowable internal psi range for the Theoben gas rams ?

Thanks.
Title: Re: The future of gas pistons???
Post by: AirScopes on July 26, 2012, 04:33:15 PM
For what it's worth and as I see it, the gas rams are the power plant of the future. They are being improved and perfected more and more as time progresses.

At the same time, I believe the springers will be around for a long time, are dependable and will always have their place, at least well into the future.
The voice of sanity right there...

Richard
Title: Re: The future of gas pistons???
Post by: Nikoman on July 26, 2012, 04:34:52 PM
Does anyone know the allowable internal psi range for the Theoben gas rams ?
I know that the max fill for the RX (HW90) series is 26 bar, although some people have filled them to 27 but that's not good for the gun in the long run.
Not sure about the other rams but the Eliminator/Crow Mag can go a little higher since the gun is a beast.
Title: Re: The future of gas pistons???
Post by: AirHunter4Ever on July 26, 2012, 04:46:22 PM
Who sells the Theoben gas rams directly to customers ?

LINK ?
Title: Re: The future of gas pistons???
Post by: Nikoman on July 26, 2012, 05:02:09 PM
If I'm not mistaken, David Slade is the sole importer for Theoben products here in the USA. You can go his website and see what's available. His place is called Airgunwerks.
He's not the only one who sells them, there's a place down in Southern California, not sure of the name but it might be Pomona Airguns(?) or something like that.
Title: Re: The future of gas pistons???
Post by: AirHunter4Ever on July 26, 2012, 05:25:17 PM
If I'm not mistaken, David Slade is the sole importer for Theoben products here in the USA. You can go his website and see what's available. His place is called Airgunwerks.
He's not the only one who sells them, there's a place down in Southern California, not sure of the name but it might be Pomona Airguns(?) or something like that.

I called both companies and basically got nowhere.  They claim they are "proprietary" and only work in "specific models" ( BS ) . . .

At any rate, I am still hunting for information.

Thanks.
Title: Re: The future of gas pistons???
Post by: Nikoman on July 26, 2012, 06:05:38 PM
Let us know what you find.
Title: Re: The future of gas pistons???
Post by: lillysdad621 on July 26, 2012, 07:06:27 PM
does anyone know what happened to the venturi rams??? i had one on a whisper and regret selling that rifle. The new one is not a venturi ram, and the new IGT has not been reviewed enough to make an educated guess...
Title: Re: The future of gas pistons???
Post by: pappa on July 26, 2012, 08:46:52 PM
On the subject of the THEOBEN Gas Rams, is it possible to buy the Gas Ram assembly by itself for installation into my own air rifles ?

Who sells them ?

Thanks.

I buy mine directly from Crosman. They cost about the same as a good spring.
Title: Re: The future of gas pistons???
Post by: AirHunter4Ever on July 26, 2012, 11:15:33 PM
On the subject of the THEOBEN Gas Rams, is it possible to buy the Gas Ram assembly by itself for installation into my own air rifles ?

Who sells them ?

Thanks.

I by mine directly from Crosman. They cost about the same as a good spring.

I'm looking for something that can be "stepped up" over the performance of a spring. Most gas rams have slightly lower velocity than springs, but offer other advantages.

Title: Re: The future of gas pistons???
Post by: tjk on July 27, 2012, 12:03:12 AM
 "Most gas rams have slightly lower velocity than springs, but offer other advantages"
Really?!? I've shot gas rammed guns that shot even better and faster than their spring equipt counterparts. The Crosman NPSS that I shot at Sams place down in Rincon Georgia was much nicer than any tuned spring powered Quest varient I have ever shot.   
Title: Re: The future of gas pistons???
Post by: Scotchmo on July 27, 2012, 12:05:25 AM
...
I'm looking for something that can be "stepped up" over the performance of a spring. Most gas rams have slightly lower velocity than springs, but offer other advantages.
Gas rams have slightly lower velocity? Not true.

If you replace the wire spring with a standard gas spring with the same maximum force, the gas spring will produce more FPE than the wire spring.
Title: Re: The future of gas pistons???
Post by: Nikoman on July 27, 2012, 12:10:45 AM
...
I'm looking for something that can be "stepped up" over the performance of a spring. Most gas rams have slightly lower velocity than springs, but offer other advantages.
Gas rams have slightly lower velocity? Not true.

If you replace the wire spring with a standard gas spring with the same maximum force, the gas spring will produce more FPE than the wire spring.

That sounds about right, I've heard of people ramming their rifles with the Theoben struts and getting higher velocity.

(Boy, that didn't sound right did it? ;D)

I'll post a full report when I get my rifle back from getting the strut installed in the next few weeks. I have extensive Chrony numbers over the years with that particular gun since it was new 15 years ago and I'm curious what kind of numbers it'll sling out of the barrel with the new powerplant. Stay tuned...
Title: Re: The future of gas pistons???
Post by: RedFeather on July 27, 2012, 12:28:42 AM
Regarding the Cardews, I didn't catch where someone was using them as an argument for or against gas pistons.  The comment I replied to was about combustion.  Agreed, combustion takes place no matter what motive force propels the piston.  (The nitrogen was used in the experiment because it is an inert gas.  Just a coincidence that many gas pistons are filled with it.)

One thing which has not been pointed out, or I might have missed that, as well, is how so many of these new pistons have no provision for regulating the power.  Not everyone wants to maximize their fps.  In fact, some "soft tune", either to have a smoother shooting gun or more accuracy.  It is not hard to do with a wound wire spring.  You can clip coils, change spacing or even swap springs.  Can you do that with a Crosman piston?  Not that I know of.  With a Theoben?  Absolutely.  At least, you can with the older pistons containing a fill valve.  The Theobens can be maintained, as well.  I believe it takes only a new O-ring kit and then replenishing the good old common air.  (Well, good depending upon where you live.)  As to the quality of the current crop of pistons, Gene did a rather nice comparison (here on the GTA) of the NPSS and the Titan.  He reported a visible increase in quality with the Crosman-made piston as compared to the Chinese.  Of course, the NPSS costs double to almost triple a WalMart Titan GP.  I will say that, compared to my stock Diana 34, my NPSS is much easier to cock while having the same, if not greater, power.  How they do that?  Guess the NPSS is a tad more efficient.
Title: Re: The future of gas pistons???
Post by: Kailua on July 27, 2012, 12:40:02 AM
Some aftermarket gas pistons have provisions to change the pressure settings.  I would think it would be expensive to have a setup to do home tuning.  May be able to use a PCP pump that is just a guess.  May need some kind of moisture filter as someone mentioned.   Tho PCP pumps do have moisture filters come to think of it.
Title: Re: The future of gas pistons???
Post by: AirScopes on July 27, 2012, 10:30:56 AM
Seems there is quite a lot of guessing going on about springs and gas ram and performance... I dont know the answers, but there are some common factors.

The size of the ram will make a difference in it fitting a gun, just like different springs fit different guns. I dont think it is a line of BS.

Springs *might* be modified by cutting coils; some gas rams I have seen look like they *might* be modified by cutting the end of the strut... and i'll assume that drops the original power.

Different guns with different ram choices and different modification will perform *differently*. A GAMO xyz with a ram installed may have greater or lower power depending on the compatibility of the ram and how it was installed.

There are likely so many variations and options that no one knows all the answers till they give something specific a try or do some homework with a micrometer or get an expert's advice. But there are a lot of times experts don't know...For a while I made part of my living hacking popular software to do things that were *impossible* and making the results available. Even when I had achieved the result and showed people they still said it was impossible. I am guessing there are at least a few with the mechanical and machining knowledge to get things that are impossible to work...it may not make it generally viable to produce/reproduce. I know I have made simple, inexpensive modifications to scope mounts with model car parts that make them many times stronger. I've seen people use a toilet flange to make a handsome sidewheel for a scope. Creative solutions can get you a lot of places ;-)

I guess what I am saying is that even first-hand experience is not an ultimate answer... Two guns can show different results even if they are the same model. The other addage..."where there is a will, there's a way..."

Sometimes I think everyone is right, and opinions get flung because experience differs. Probably best to focus on what has worked, why specifically something failed and how things were achieved than to look at the results.

Geeze, did that make sense?

Richard

Title: Re: The future of gas pistons???
Post by: silverback2000 on July 27, 2012, 12:26:25 PM
 :o if I'm out in the field and my gun has a safety. There's no reason for me to not have it cocked unless I've just fired. A spring isn't going to suffer too much from being cocked for an hour or so. I loved my pump innova and I would like a nitro but lots of people love springers. Compare to motorbikes. Harley-Davidson are so slow clumsy thirsty and old fashioned compared to jap and Euro bikes but people love their tough ever fixable simplicity and will always love them. Same goes for springers.