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domer_pyle · Senior Member

The test of my XL is always to make sure CPUM/CPHP cross the line at 900 at least. Today I put one across and it only hit 864 fps, and it kept a tight spread on all shots after. So would it be safe to assume my ram is slowly taking a dump? If it was the seal or anything like that the ES would be much greater than it is. Never had a rammed gun before so I don't know how to tell when it's on it's way out

Sholo · Veteran Member

Don,t know if this helps or not, but my benji trail shot really hard at first (can't give exact fps-didn't have a chrony at the time). then it gradually got weaker and weaker, and POI was all over the place. By the time I got a chrony,it was down to 375 fps! Re-sealed it with a kit from Eric, but only bumped fps to 450 or so. Obviously the ram is done - just don't know if it was done from day 1, or my repeated shooting with a defective seal(less backpressure) caused the ram to fail. New ram from Eric is only around $45

Todd

domer_pyle · Senior Member

Hmm, interesting, thanks. Eric if you're reading, I'll be getting ahold of you in the next few weeks!

The ram slowly leaking is all I can think the problem could be, it had the same ES as when it was at full power.

rsterne · Moderator

From what I have seen on the forums, 870-890 is more typical than 900+ for the XL 1100 with CHUM / CPHP 14.3 gr.... My guess is that the lube is slowly burning off and the "combustion" phase of springer operation is reducing.... Even though it's a gam ram, it's still a springer, it just uses compressed air for a spring to move the seal which compresses the air....

Bob

AirGunEric · Site Admin

I think Bob maybe has it.

What I've seen/heard of so far- when the strut starts going, it's a fairly significant fail- i.e. 890fps one day, 600fps the next, a few days later 400fps.

These things are the same technology as a strut on the hood/trunk of your car and seem to fail the same way- in significant stages, not gradual, minimal losses.

domer_pyle · Senior Member

Weird, after the tune it always hit 9 or just over with a tight ES. Thanks for the info though, glad I didn't up and spend the cash without asking.

jimineecricket · Member

the nitrogen filled gas ram will break in and losse some of its kick along the way. They can leak slow or fast depending on how they start to fail. I have seen struts that hang on for a long time after loosing some of there gas. My best example is the hatch back car in summer the struts hold it up just fine and winter it wont hold it up it use to work fine but as it wore and lost a charge the pressure drops and in the cold it drops more.

Thats cold effects them too it is just not very noticable when they are new and full of gas the react alot less to cold than a spring but they still react.

Thats been a concern of mine for awhile is how long will they really last. All the hype says longer than a metal spring experieince tells me they are full of puppy DOO! Yea I said it puppy DOOOOO!!

I love the way the nitro piston shoot smooth and hard no vibration or twist but those gas struts are built CHeesy style and hold a ton of pressure how good are the seals how good is the cylinder for 45 beans I am not feeling the love. Just my thoughts shoot it see if it settles in or dust off the cobb webs and let the bats out of that pocket book of yours :0 when you gonna take me to the range so I can teach you how too shoot????

domer_pyle · Senior Member

Soon I tell ya, first shift should only be right around the corner! And maybe even this weekend, I don't think I have much going on. Plus I've been itching to get this Disco out to some distances with it's new goodies

domer_pyle · Senior Member

Sure enough, the ram was leaking, and slower than molasses, not a quick blowout by any means. From the time of the last post til now Premiers dropped to 830, and Polymags 800. Got a new ram a couple weeks ago and I'm back on point, just a tad slower. Polys average right around 830-840 and Premiers are hovering right around 890. We'll see how long this one holds up!