Gas Ram conversions
Printed From: Kiwi Airgunners
Category: Technical
Forum Name: Pauly's Technical Area
Forum Description: Technical information, Modifications and DIY projects are all in here
URL: www.kiwiairgunners.co.nz/forum_posts.asp?TID=32
Printed Date: 23 Nov 2024 at 3:11pm
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Topic: Gas Ram conversions
Posted By: nunga
Subject: Gas Ram conversions
Date Posted: 18 Apr 2013 at 5:52pm
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I am looking into gas rams or as the air gunning community calls them the nitro pistons, doing lots of research and waiting for some answers to come back from some manufactures. If all goes well (and i pray that it does)I will be able do conversions for most springers. Watch this space! |
Replies:
Posted By: Raizer
Date Posted: 18 Apr 2013 at 6:36pm
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You have my interest, my Striker is sweet now, but a ram would be nice! |
Posted By: (pink)MIST
Date Posted: 18 Apr 2013 at 8:15pm
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doing the conversion is easy, tuning it to do what you want.... theres the trick :) my crosman "cough cough" quest (more of a mongrel than your average south auckland dog) has a gasram , quieter, smoother, more power and consistent through different temps and altitudes. My Hatsan has one as well, and will sit on 790fps for hundreds of shots in a row. I guess its one of those things that until you have it you're sceptical, but once you have it you'd never go back. ------------- NZAFTA President 1st place HP springer - 2014 WFTF Worlds 1st place HP springer - 2014 Nats AA TX200 MK111, Optisan Viper 8-32x60 JSB. VMach, TbT, maestro design. |
Posted By: Hidayat
Date Posted: 21 Apr 2013 at 2:37pm
Is that true or joking if fixed barrel gun cannot to be gas ramed?if true why?i'm not technician only partime pest controler ------------- NOTHING IMPOSSIBLE EVEN ONLY WITH 200FPS |
Posted By: Raizer
Date Posted: 21 Apr 2013 at 7:11pm
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Many fixed barrel guns can be rammed just the same as break barrels. But lots of guns like Weihrauchs etc can not be rammed due to the trigger latch coming out of the middle of the piston 
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Posted By: Snoobab
Date Posted: 01 May 2013 at 10:50pm
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So that would be pretty much the same for an AATX200hc wouldn't it. ------------- "I feel the same way about disco as I do about herpes". - Hunter S. Thompson |
Posted By: Raizer
Date Posted: 02 May 2013 at 12:34am
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Yeah I believe so. |
Posted By: (pink)MIST
Date Posted: 02 May 2013 at 8:48pm
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well there goes that idea i had......, its all good tho, we're in NZ, the land of ingenuity :) SURELY someone will figure out how to get it done sometime ------------- NZAFTA President 1st place HP springer - 2014 WFTF Worlds 1st place HP springer - 2014 Nats AA TX200 MK111, Optisan Viper 8-32x60 JSB. VMach, TbT, maestro design. |
Posted By: nunga
Date Posted: 30 May 2013 at 8:59pm
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With a bit of luck i should have my first gun converted over the long weekend :) will keep you posted. |
Posted By: (pink)MIST
Date Posted: 02 Jun 2013 at 9:38pm
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i feel i pic thread coming on :) ------------- NZAFTA President 1st place HP springer - 2014 WFTF Worlds 1st place HP springer - 2014 Nats AA TX200 MK111, Optisan Viper 8-32x60 JSB. VMach, TbT, maestro design. |
Posted By: nunga
Date Posted: 13 Jun 2013 at 4:20pm
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Ok i have my new ram. I am converting my old Crosman first to see how it goes. I have spent the most part of the day sorting it out and have finished it just now. It is getting dark outside and the rain is coming so i will test it tomorrow if the weather lets me. The New RAM.  I made a home made valve spring compressor to compress the Gas Ram. As you can see it is very simple but does the job nicely  The ram fits nicely almost like a brought one!!, Just need to finish putting it back together now.   So thats what i have done so far. Testing will be tomorrow. |
Posted By: (pink)MIST
Date Posted: 13 Jun 2013 at 9:32pm
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waiting to see how yours turns out. what model crosman are you converting? calibre ? do you have pre - gasram chrony figures to compare with as well? And what brand of gasram are you using? (stabila, theoben , benjamin, etc) When mine was done, and I first heard it being shot, I felt disheartned at first. Quieter and a lot less visible recoil. surely these were signs of a drop in power..... nope a slight power gain was had, matched with alot more consistency in chrony results. That plus less felt recoil meant alot more hits were going exactly where I asked them to, on paper the groups shrank in size considerably. ------------- NZAFTA President 1st place HP springer - 2014 WFTF Worlds 1st place HP springer - 2014 Nats AA TX200 MK111, Optisan Viper 8-32x60 JSB. VMach, TbT, maestro design. |
Posted By: nunga
Date Posted: 14 Jun 2013 at 1:11pm
The gun is .22 Crosman Optimus. Pre gas ram was 680fps with RWS super dome. after the conversion 750fps. The gas ram is a no-name. It was built to my specs what i asked for :). She is currently sitting on 60KG of moving force. I have ordered a second strut but this one is charged to 90KG. it also has been made with a touch of oil between the main seals to keep the seals from drying out this will also act as a damper system. When the strut is near its d-compressed state it wont hit so hard at it's last 2mm of stroke this should keep the seals intact longer and have less of a kick. it is rated to 20,000 compressions before it will need re gassing. It will be here mid next week. Keep you posted ! |
(pink)MIST wrote:Posted By: nunga
Date Posted: 20 Jun 2013 at 9:21am
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My supplier just got in touch with me. the beast will be here tomorrow. I will install it tomorrow afternoon and hopefully have it tested by tomorrow night. Hope the weather blows over and fines up a bit by then. Very excited at the moment ha ha :) |
Posted By: (pink)MIST
Date Posted: 20 Jun 2013 at 6:59pm
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saturday and sunday are looking good for the weather, i wouldnt hold my breath for friday though when mine was first done, the lack of recoil provided a huge improvement in feel and accuracy. If you havent done the GRT trigger replacement yet, then youre in for a treat once you do, after shooting gasrams for so long, I almost found it hard to go to the TX200, and on some points i like the feel of the gasram better still. Now if only someone would figure out how to ram a TX............. ------------- NZAFTA President 1st place HP springer - 2014 WFTF Worlds 1st place HP springer - 2014 Nats AA TX200 MK111, Optisan Viper 8-32x60 JSB. VMach, TbT, maestro design. |
Posted By: nunga
Date Posted: 20 Jun 2013 at 11:01pm
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I do have some ideas about that TX problem, but need a sample to play with. |
Posted By: nunga
Date Posted: 28 Jun 2013 at 8:32pm
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Well i have the new high spec ram installed in the gun today but i have noticed right off the bat that it would not preform as i would like, I could see this even before i installed it. the outer shaft seal is not what i wanted and i could see it would not do the job. Used using a simple compression test on the bench I could tell they did not put the vent groves in like i wanted and as a result when the pressure is released off the ram there is back pressure building up inside the seal and this will restrict the movement of the shaft moving forward. I did install it just to see what would happen but as i thought the thing did not preform. Very disappointed in the end result. I took a hacksaw to the base of the ram and cut the end off. pulled the ram apart and checked it to see how they made it. It looks very simple and i can easily knock one up in my workshop with the specs that i know will work. I can see improvements of the ram that they have sent me that will increase the life span of the ram as well. Will keep you posted |
Posted By: nunga
Date Posted: 10 Oct 2013 at 11:04pm
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Just an update. I have been holding off on this for a little bit as i have had a part on my lath brake and have only just managed to get a replacement part shipped in from England. I am hoping it will be here tomorrow and can start work on the ram over the weekend. |
Posted By: Grantrow
Date Posted: 12 Oct 2013 at 11:08am
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Greetings. This is my first post. I signed up last night. Any way, I am new to air rifles / air guns, but have been reading a lot about them lately, and am keen to get my hands on a good reliable, QUIET, low recoil air rifle, that is easily capable of knocking over possums, and is accurate. I don't have a FAL, and can't be bothered with getting one again. I have a possum v fruit tree problem !! (sorry - not trying to side track this thread) Anyway . . . I am interested in this topic regarding conversion from spring to gas ram. Can any / most spring guns be converted ? I'm not technical, but could most gun shops do a conversion if a ram was obtained ? Good luck with your conversion. You obviously have pretty good technical skills to manage this process. I will be keen to read your results. Cheers, Grant. |
Posted By: nunga
Date Posted: 14 Oct 2013 at 11:59pm
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Well i just got in from the garage, My new part came in the post this morning so i have been in the garage installing it. I had to machine up a new bush for it before it fit. ( i dont think it was the exact model that i ordered) Everything is good now :) very happy camper at the moment. The auto feed and thread cutting is back online :) Grant, most rifles can be converted with the exception of the guns like Weihrauchs etc these can not be rammed due to the trigger latch coming out of the middle of the piston. But if anyone has one they are willing to donate for science I do have some ideas :) |
Posted By: nunga
Date Posted: 22 Oct 2013 at 11:36am
I decided to start my gas ram again from scratch. The parts that they supply just do not look like they would last very long so I have got my tube i will be using and i have just finished the seal for the piston. I decided to do the seal first because it is the hardest for me to machine. The plastic does not like fine cuts so i can machine the tube out or make the shaft step to suit the internal hole in the plastic. After machining the OD of the plastic it is time to do the internal hole.  Next i need to machine a angle on the OD so the plastic will expand to seal against the iner tube wall when pressure is added to it.  You cant really see the angle because my light is not the best but it is good :) Tonight i will machine up the piston and shaft. |
Posted By: nunga
Date Posted: 23 Oct 2013 at 11:37pm
Just finished the shaft - piston.    This is the finished item with the seal fitted. I will do the tube and bearing over the next few days :) |
Posted By: (pink)MIST
Date Posted: 24 Oct 2013 at 12:25pm
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Looking interesting mate, watching this build :) ------------- NZAFTA President 1st place HP springer - 2014 WFTF Worlds 1st place HP springer - 2014 Nats AA TX200 MK111, Optisan Viper 8-32x60 JSB. VMach, TbT, maestro design. |
Posted By: nunga
Date Posted: 25 Oct 2013 at 11:52am
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Did some quick testing last night. machined up a test tube with a bike inner tube valve on one end to put some pressure in. I managed to get it to hold 90PSI with out any leaks. Then did a compression of the shaft and watched the pressure rise to 150 before the valve gave way. The seal its self it sweet i just need to work on the filling part. :) |
Posted By: nunga
Date Posted: 25 Oct 2013 at 3:58pm
 This is my test tube with the inner tube valve :) I have just figured out a cool little one way valve that wont take up space inside the tube so the piston shouldnt hit it. I will try to get it done tonight because i have just been told that we are going away for the long weekend..... and the dragon-inlaw ops... my mother in law will be joining us. |
Posted By: nunga
Date Posted: 31 Oct 2013 at 12:28am
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Well i finished the new the end plug with the valve, sorry didnt take photos this time. Will do some pressure testing tomorrow and if all goes well i will put in the gun and see how it goes. But it is looking good so far. |
Posted By: (pink)MIST
Date Posted: 31 Oct 2013 at 12:21pm
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Nice work bud, if you'd had it together earlier it might have helped with your dragon problem :) ------------- NZAFTA President 1st place HP springer - 2014 WFTF Worlds 1st place HP springer - 2014 Nats AA TX200 MK111, Optisan Viper 8-32x60 JSB. VMach, TbT, maestro design. |
Posted By: nunga
Date Posted: 03 Nov 2013 at 5:23pm
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ha ha yea :) Update. Finished testing and i managed to get just over 350psi into the ram using an old fridge compressor. Fitted it back into the gun and fired a few rounds to see how it did. I used the same tin of .22 RWS super dome that i used before. Here is the results through the chrony. I got around 20fps difference between shots. I will have to look at the main shaft seal in the ram because i think the friction is causing the changes in the FPS. But all in all i am happy with the way the ram is sealing. It will need some tweaking but it is well on the way.   |
Posted By: (pink)MIST
Date Posted: 03 Nov 2013 at 7:12pm
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944 from a .22 is bloody good! The second photo at 365...... Not so much :) ------------- NZAFTA President 1st place HP springer - 2014 WFTF Worlds 1st place HP springer - 2014 Nats AA TX200 MK111, Optisan Viper 8-32x60 JSB. VMach, TbT, maestro design. |
Posted By: nunga
Date Posted: 03 Nov 2013 at 7:24pm
thats a 9 not a 3 :) |
Posted By: (pink)MIST
Date Posted: 03 Nov 2013 at 7:31pm
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thats all good then, bloody reflections on photos :) Think that'd definately fall into the "open" or "high power" class, would make for a flatter trajectpry as well ------------- NZAFTA President 1st place HP springer - 2014 WFTF Worlds 1st place HP springer - 2014 Nats AA TX200 MK111, Optisan Viper 8-32x60 JSB. VMach, TbT, maestro design. |
Posted By: poorshot
Date Posted: 04 Nov 2013 at 1:23pm
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And I am hesitating taking my gun to bits to check lube and assembly! Very impressive I would say. What kind of end result will make you happy or are you just going to keep refining it? ------------- It's all fun and games and then somebody looses an eye. |
Posted By: nunga
Date Posted: 08 Nov 2013 at 8:14pm
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Will be taking it out tonight for field testing :) Will keep you posted Poorshot, When you get the bug, you are never happy and will keep trying to refining it :) |