JOAO's American Arms Gas Ram Conversion Has Been Tested in a 125 Sniper !

[Tarheel]

Gene has installed and tested on of JOAO's American Arms gas ram conversions in a Hatsan 125 Sniper in .22 caliber.

http://www.gatewaytoairguns.org/GTA/index.php/topic,30447.msg280898.html#msg280898

940 fps w / 14.3 gr = 28.06 fpe

832 fps w / 18.1 gr = 27.83 fpe

10 fps less than the stock spring and 35 - 40 fps faster than the Moeller "Red" gas ram w/ an Average Force of 197 lb . . .  Now, we have a "baseline to compare the Moeller "Yellow" gas ram to w / an Average Force of 253.5 lb .

I don't know the extent of tuning that Gene did to the rifle, other than de-burring & cross-hatching, but the numbers are valid for comparison.

NOTE: The parts, "as delivered" did not fit and required custom machining by Gene to make the conversion kit work.

Dave

[Smackey54]

That velocity is about what I get with my XL gas spring in the WFH....today I consistently got 961fps...or 29.3fpe with 14.3gr CPHPs. Different sized compression chamber and swept volume?
Mark

[fortyshooter]

Wonder how that will translate to the .25 cal.?  I'm in the 800-804 range with 19.9 gr. H&N FT pellets,stock out the Hatsan box. My rifle was also picked and chronyed by PA and their figures match mine.

[Tarheel]

That velocity is about what I get with my XL gas spring in the WFH....today I consistently got 961fps...or 29.3fpe with 14.3gr CPHPs. Different sized compression chamber and swept volume?
Mark

The Bore is 29mm and the Stroke is 120mm in all Hatsan 125's . . . 30mm diameter x 120mm stroke in the 135.

Dave

[Tarheel]

Wonder how that will translate to the .25 cal.?  I'm in the 800-804 range with 19.9 gr. H&N FT pellets,stock out the Hatsan box. My rifle was also picked and chronyed by PA and their figures match mine.

800 - 804 fps  w /19.9 gr pellets = 28.29 - 28.57 fpe

Gene reported a 15 - 20 fps drop with Joao's kit, compared to the stock spring . . .

If a "ballpark" 15-20 fps drop is used,  an 802 fps average velocity becomes a 782 - 787 fps w / 19.9 gr pellets = 27.03 - 27.37 fpe

The Moeller "Yellow" gas ram should increase performance by a "hypothetical" 14% over the "Red" gas ram . . . We need to include the drop in velocity from the stock spring when using the "Red" gas ram, as a basis for comparison . . .

Using a "theoretical" 14% increase in velocity from "Red" numbers, the new velocity with the "Yellow" gas ram in a .25 would be 863 - 868 fps w / 19.9 gr. pellets = 32.92 - 33.30 fpe  . . .

Remember, this is STRICTLY "hypothetical" and only for "guesstimation" purposes . . .

Dave

[Ray]

Would you get the same results with the trail ram in a 125 sniper?

That velocity is about what I get with my XL gas spring in the WFH....today I consistently got 961fps...or 29.3fpe with 14.3gr CPHPs. Different sized compression chamber and swept volume?
Mark

[Tarheel]

Would you get the same results with the trail ram in a 125 sniper?

That velocity is about what I get with my XL gas spring in the WFH....today I consistently got 961fps...or 29.3fpe with 14.3gr CPHPs. Different sized compression chamber and swept volume?
Mark

Assuming the rifles were identical, the XL gas ram would provide a 20 fps "edge" over Joao's gas ram, but we have to remember that Mark had other work done to his rifle . . .

Probably, a "toss-up" in the "real world" . . .

However, that extra 21 fps would provide an additional 1.27 fpe w / 4.3 gr pellets over Joao's gas ram numbers, making them 961 fps = 29.33 fpe w / 14.3 gr pellets and 853 fps = 32.16 fpe w / 19.9 gr pellets.

Just "hypothetical numbers" . . .

Dave

[Bryan Heimann]

The XL rams are not quite as consistent as they should be, I think you'll have a more consistent result from the other rams as a result of better quality control.  Manufacturers of industrial gas rams are probably used to being held accountable for inconsistencies in the amount of force generated by a ram, and it's effect on machinery vs. the crosman nitro piston, which goes in a crosman gun and all the end point consumer knows is that he's got a hammer of an airgun- probably not going to check the force of the ram.  But i'm only speculating on the industrial rams.  I could be off by a mile...

[Tarheel]

The XL rams are not quite as consistent as they should be, I think you'll have a more consistent result from the other rams as a result of better quality control.  Manufacturers of industrial gas rams are probably used to being held accountable for inconsistencies in the amount of force generated by a ram, and it's effect on machinery vs. the crosman nitro piston, which goes in a crosman gun and all the end point consumer knows is that he's got a hammer of an airgun- probably not going to check the force of the ram.  But i'm only speculating on the industrial rams.  I could be off by a mile...

Bryan,

Nope, I think you are "right on target" about commercial Nitrogen Gas Springs . . .

Dave

[bluzjamer]

Moller needs to come out with a rel-low spring. One that is between the red and the yellow for just us airgunners. Then if they can get it into the Crossman price range that would be real nice.
I'd be fine with the crossman fps and fpe, sounds good to me if they last.

[Tarheel]

Moller needs to come out with a rel-low spring. One that is between the red and the yellow for just us airgunners. Then if they can get it into the Crossman price range that would be real nice.
I'd be fine with the crossman fps and fpe, sounds good to me if they last.

All of the Nitrogen Gas Springs are adjustable in pressure . . . Get a high-pressure gas ram and "bleed off" pressure until it is lowered to the desired level.

If you go too low, you have to send it back to the manufacturer to have it re-pressurized, unless you have the necessary equipment to handle Nitrogen and pump it up over 2600 psi ( 180 bar )

Dave

[WHITEFANG]

Crosman rams are not adjustable to my knowledge. The XL ram, If I received the correct ram is 1/4 shorter on the barrel and the shortness on the shaft. You need to remember I bought one of the WFH from PA a year a go with the nitro installed and after all the hype of the fire blazing withthe HATSAN have dis assembled the the gun and stripped it of the conversion. The WFH ram is not the XL. So I have 1 version of the conversion in my hands. It is proved that one can make the XL work and work safe. I can at will test the difference of the 2 rams in load carrying.
In the WFH, the gun was consistant and a gun I could grab and shoot with no issues at all. Yes the RE-BRANDED USA HATSAN, THE WALTHER!!!! EVEN AFTER A BARREL MISHAP AND A CHOP JOB THE GUN WAS STILL A KEEPER. SO THE CONVERSION HYPE HITS. i PULL THE GUN A PART AND STRIP THE RAM AND PUT THE SPRING BACK IN. Now the gun puts out more FPS but is a hand full. GUN IS ON BUT NOT A TAME GUN. So the ram helps remove the torquing,twisting and recoil with loss of FPS. As we all know speed is not always good FOR ACCURATENCY.
I am glad THAT GENE has stepped in on the conversion. As a MODERATER OF THE FORUM AND A MODDER IN THE HOBBY: He can be of help in this conversion with the main thing we need to remember SAFETY. Yes it is a given he is not going to want a maximum limitation exceeded on any mod. LIABILITY!!! RESPONSIBLITY!!!SAFETY!!!!
Maxing out anything is pushing THE safety concern and the life of what ever you are testing. Example: In my SUPERCHARGED trk I could turn more RPM'S get more HP at the rear wheels THUS MAKING THE TRK MUCH MORE QUICKER. But it is not safe for all the componets in the drivetrain.
Yes this is the same on the guns. 25 fps more in comparison to 1000 RPMS AND 25 more HP. But how long will it last. My tuner will not give me the extra 1000 RPMS for the same reason GENE WILL NOT. LIABILITY!!! RESPONSIBLITY!!!SAFETY!!!!
 So there are two sides of SAFETY. Safety for your health and being and safety for the product lasting. Well so much for the SOAP BOX start of the day

[WHITEFANG]

Yes I am back on the soap box!! I just thought about one more thing:
Being in a dangerous line of work, BEING A SAFETY and QC MANAGER, I am responsible for the life's of many people. My goal is to send everone home as they came to work. General industry and construction standards have different OSHA GUIDELINES. OSHA REGULATIONS AND STANDARDS ARE DIFFERENT FOR BOTH. OSHA regulations are witten in BLOOD. Someone has either been injured or killed resulting in a new safety guideline. All manufactures have warnings to not exceed manufactures recognitions. Again: SAFETY, LIABILITY AND THE LIFE OF THE PRODUCT. Anytime you exceed the warning you are assuming all of this at your own RISK. So as it is the things we do and share are great but it is not a given that the result will be the same for the next.
Joa has GENE testing or blessing his conversion for more reasons than meets the eye. As I look at 3 guns sitting on my patio loaded the last thing I want is for one to go off even with the SAFETY ON. As I have mentioned in many post; STORED ENERGY OF ANY TYPE IS NOT TO BE TAKEN FOR GRANIT!!!Safety should never sleep because danger lurks at all times NEVER SLEEPING and is around ever corner just wainting on the prime time to strike.
Sorry to bore you and the rant!!!
 Please just think a little about what I have shared with all of you on the SAFETY topic and lets all use good judgement in our actions with these MODS and the air guns. These are not RED RIDERS and you can shoot your eye out.

[ezman604]

All of the Nitrogen Gas Springs are adjustable in pressure . . . Get a high-pressure gas ram and "bleed off" pressure until it is lowered to the desired level.

If you go too low, you have to send it back to the manufacturer to have it re-pressurized, unless you have the necessary equipment to handle Nitrogen and pump it up over 2600 psi ( 180 bar )

Dave

Whitefang makes an EXCELLENT point. SAFETY is concern #1 on GTA. DO NOT tamper with a nitrogen piston unless you have the specific equipment and the training to service them. DO NOT attempt to open, purge or adjust the contents of a nitrogen filled device!!!! PERIOD!!!!
Order the pressure you want and leave it at that. If you need a different pressure, order it filled to your specs.

[Paul68]

I plan on my collection having representations from different aspects of the air gun hobby. High quality springers, clones, pumpers, PCP, ect, you get the idea. I also plan on having a modified and max power category. To that end, I'm sure I'll have a couple that are past ridiculous speed, and well into "ludicrous speed!". They may not be the most reliable or accurate once I have em, but they'll be great for shocking anyone who wants to try out one of my "BB" guns lol. Safety, sure it's critically important. Modifying your personal AG's is all about personal responsibility, no one to blame but yourself if you send a spring through the wall or your head, so you'd better be sure of what you're doing. Start working on others before you truly understand what's going on though, you're on pretty shaky ground.

These are not firearms, but the same rules and level of diligence applies. Protect others above all else, and yourself next. Personally, I am deliberately taking my time working up to more complex tuning and modifications, simply because if you skip the steps between simple cleaning/lubing and all out custom fabrication, you are skipping all the hands on experience and lessons that come with it. There are too many nuances, tricks, manufacturer deviations within same models, to simply assume what you read or see others do will be sufficient. Not to mention the need to fully understand tolerances, metal properties, safety margins etc.

Nope, I'll wait until I have the confidence in my skills before I start putting AG's to the limit. Which will be around next week lol J/K

That said.....

 

[CharlieDaTuna]

Dez is right as is Paul68 and WhiteFang. Gene and I have been following this pretty closely, discussed it several times and are greatly concerned about safety factors and how it may affect members safety.

 Just because Gene installed and tested one does not make it something to not be concerned about and was not his intent. The testing was nothing more than comparable differences with the ram provided and a spring as well as the modifications needed to make a conversion kit and not safety related and did not include long term field testing or making "adjustments" to rams. Do not make Gene's testing more than what it is.

This thread and all related threads are sitting on the fence and may be moved or perhaps even deleted in the not to distant future. We'll see what happens and how this progresses but we do have great safety concerns, especially when it comes to the membership.

CDT

[Smackey54]

I found the XL ram was about 1/8 inch longer than the N-Forcer yellow 120mm. I went away from the N-forcer yellow as it did not improve the fpe by much, and was very difficult to cock...and places much higher pressures on the trigger components, and on the stock when cocking. As I am now getting about the same (+/- .5fpe) with the XL gas spring compared to the stock spring, I am happy with it for the much tamer and consistent shot cycle.

The N-Forcer gas spring got me about 2.5-3 fpe more, but, as I am approaching the age of 60, I found it extremely difficult to cock and not worth the effort to gain the couple of extra fpe. I found the cylinder hone, JM seal, polishing, deburring and proper lubrication improved the stock spring performance by about 1fpe. It did quiet it down some, but not as much as topping off the tune with the conversion to the XL piston. I am not afraid to leave the gun cocked for short periods of time with the XL piston. I was very wary and did not feel comfortable doing that with the N-Forcer installed. 

If you are going to experiment, IMHO, you have to consider the power versus shooting pleasure and ease balance.

Just my $.02

Mark

[bluzjamer]

+1 Mark

[Mike 4888blues]

I found the XL ram was about 1/8 inch longer than the N-Forcer yellow 120mm. I went away from the N-forcer yellow as it did not improve the fpe by much, and was very difficult to cock...and places much higher pressures on the trigger components, and on the stock when cocking. As I am now getting about the same (+/- .5fpe) with the XL gas spring compared to the stock spring, I am happy with it for the much tamer and consistent shot cycle.

The N-Forcer gas spring got me about 2.5-3 fpe more, but, as I am approaching the age of 60, I found it extremely difficult to cock and not worth the effort to gain the couple of extra fpe. I found the cylinder hone, JM seal, polishing, deburring and proper lubrication improved the stock spring performance by about 1fpe. It did quiet it down some, but not as much as topping off the tune with the conversion to the XL piston. I am not afraid to leave the gun cocked for short periods of time with the XL piston. I was very wary and did not feel comfortable doing that with the N-Forcer installed. 

If you are going to experiment, IMHO, you have to consider the power versus shooting pleasure and ease balance.

Just my $.02

Mark

 So far different gas rams have been tested for cocking, and what power it produces,the moller yellow is next, the red was not bad, the cocking equaled  the same as the wfh with its main spring producing 900 fps in a .22 using 14.3 grn pellet.

 Common sense tell us if the wfh or sniper in .22 gets 950 fps with its main spring ,then we can choose to adjust the moller yellow to the same fps or a little higher.

950 fps is a very sweet spot,and 980 may be just the same, now it will come down to the over all cocking,the moller red was on par with the cocking effort of the stock Walter falcon hunter, the yellow moller ram should prove to be just a little more, either way the better news is that it is adjustable, and can be suited to individual preference.

So far the price on the moller was 60.00 plus shipping cost, Mark was fine with his Xl piston and he can buy two Xl pistons for the price of one, so it is buyers choice,and buyers choice is always a good thing!

[Mike 4888blues]

The XL rams are not quite as consistent as they should be, I think you'll have a more consistent result from the other rams as a result of better quality control.  Manufacturers of industrial gas rams are probably used to being held accountable for inconsistencies in the amount of force generated by a ram, and it's effect on machinery vs. the crosman nitro piston, which goes in a crosman gun and all the end point consumer knows is that he's got a hammer of an airgun- probably not going to check the force of the ram.  But i'm only speculating on the industrial rams.  I could be off by a mile...

I think you are right as well, common sense we know how the world works, that's a valid point.

 There is nothing wrong with seeking the best results for overall performance,there is something wrong when you are treated like you are a idiot and posess no working knowledge  because of greed !