6k Nitrogen tank

Can nitrogen be used in PCPs?[/QUOTE]https://www.pyramydair.com/blog/2008/01/can-nitrogen-be-used-in-pcps/embed/

I wanted to go with nitrogen when I started in the hobbywhat stopped was I had difficulty getting rental tank for my home. I think it’s a good option as the bottled N is dry no moisture to worry about in addition to the tank you need a gauge and fill harness for your tank and a way of also filling a smaller tank to give you mobility with a 4500 psi tank.

Been using Nitrogen for years. Cost me about $150 a year for rental and fills. So nice to just crack the valve and fill the gun, and knowing you dont have to worry about any moisture at all in my guns.
The part that's going to cost you is the High pressure regulator.

What you're looking for is a "Ninja High Pressure Fill Station" or Ninja HPFS. This fill station is designer to connect to nitrogen tanks with a CGA 677 fitting.

Here's a video of it on a 6k nitrogen bulk tank:

Mfg site where you might be able to order directly if you get in contact with them:
http://www.ninjapaintball.com/fillstations

Few retailers I found in a quick search:
https://blackopswebstore.com/products/copy-of-48-cubic-inch-3000-psi-aluminum-ninja-tank-1

https://airtanksplus.com/product/ninja-high-pressure-fill-station/

I have two 6K N2 tanks. going to the city to pay my yearly rent of $68 tomorrow.

Thurmond

(corrected model number required for regulator!) I recently got a 6000 psi nitrogen tank as well. For me the tank rental is $90 per year and dry N2 is $60 per fill. With incidentals ($7 energy & fuel charge, $6.95 hazmat charge and $35 delivery charge), the total comes to $199 per year if I only need to fill it once per year.

The biggest expense going this route is a CGA 347 677 regulator that can handle 6000 psi and output 4500 psi to the line. I happened to find one sitting unused in my lab - otherwise that regulator can run $400 easy (more like $600 for a good dual-stage one). The previous poster mentions a CGA 477 fitting, which I've never heard of. Maybe that was a typo and he meant CGA 347 677? There is a European DIN 477 fitting, but that's for CO2. I'm pretty certain you'd want a CGA 347 677 regulator to do this safely. The local Praxair guy actually called me to make sure I had the right regulator before sending out the cylinder.

If you have one, this is a great way to go - the nitrogen is completely dry and pure. The lowest grade I can purchase is "high purity 4.8" (99.998% nitrogen) and it has only 3 parts per million water. 3ppm water corresponds to a dew point of -92F or a relative humidity at 70*F of 0.01% (not 1% but 0.01% - completely dry). You'll never even get close to that level of dryness with any other (affordable) method. The tank they delivered is called a type 6K and it has an internal volume of 43 liters - at 6000psi that comes to 502CF of nitrogen (roughly 400+ refills of a synrod). It's a sweet way to go - but again, only if you don't have to buy the CGA 347 677 regulator. Anyway, hope that info is somewhat helpful.

prfssrlee,
I made a typo that I just corrected. I meant CGA 677. I know 677 is used for Nitrogen, Argon, Helium, but I didn't realise CGA 347 (standard on SCBA) is used for N2 as well.

I think the important takeaway is to call your tank supplier and find out which fitting they use on their tank, before ordering the fill station.

Where do you guys live to rent the nitrogen tanks.
As of right now there is no way it' feasible for me to do this in Hawaii?
Anyone in az does this? But dos it really matter in that state. Humidity gets as low as 20% or less. So moisture is very little to begin with.

In a nitrogen system is there a worthwhile way of using all the N by adding a 2nd tank and a compressor

Please pardon my ignorance, but why do you need a regulator. If you are going to dispense to a smaller 4500 or 3000 psi bottle, why can't you just carefully use the tank valve manually the same as you would fill your gun from a scba or scuba tank? All you would need would be an adaptor to fit the tank valve to either a Foster or directly attached 630 bar rated microbore hose. I would think you could rig something up for under $50. I know this setup might be a bit touchy to fill a small gun cylinder but it should be fine filling a larger bottle.

@Hollowpoint- Actually, I too made a mistake. It was getting pretty late last night and I must've been sleepy. I've since corrected to CGA 677, as you say. I wanted to correct that right away before anyone bought the wrong regulator for these high pressures. It is CGA 677 as Hollowpoint says! Definitely *not* the standard SCBA fittings (which are 347). Apologies for the confusion.

@Rey - I live in Massachusetts, about 25 miles north of Boston. It is fairly easy to get industrial and scientific things in this area since there is a big city close by.

@Brian10956 - I've been filling my 6.8L tank to 4500 psi. Once the big nitrogen cylinder drops under that, I'll just use it to fill to whatever pressure it can and top off the rest of the way with my YH. Good question as to what to do once it drops below about 2800 psi. One thing I'll probably do at that point is run an experiment I've been wanting to do - going to try boosting the input of the YH to see how much that speeds up filling. Just have to re-thread the air input port to something useful. If that works (which it should), I'll just set the regulator to about 150 psi and feed the YH with it.

@Eaglebeak - While I wouldn't recommend it, I suppose technically if your fittings don't leak and if they are designed to handle the repeated stress of cycling up and down between atmosphere and 6000 psi, then it would be functional. But the 6K cylinder tank valve is very heavy duty (pic attached) and not conducive to tiny manual adjustments. It's really an open/closed valve. I've never had much success at cracking open a big gas cylinder valve. The regulator is expensive, but as many people here have stated, these high pressures can be dangerous. I'd consider the regulator expense a sunk cost - buy it once and don't think about it ever again. I have regulators in the lab that are 15 years old and still functioning like new.

Here is a pic of the N2 tank (red) setup attached to a 45-min bottle via microbore hose. The regulator on the grey UHP Ar tank behind the red nitrogen tank is at least 15 years old and still working perfectly (it's for a 4000 psi tank with 200 psi output).

Regulators can be obtained for far less than $400.....

https://www.augustindustries.com/adjustable-regulator-0-6000-psi-reg-6000.asp

Gauges for $12

http://www.surpluscenter.com/Air-Pneumatics/Pressure-Gauges/Pressure-Vacuum-Gauges/6000-PSI-2-5-LF-LM-Gauge-21-1246-M.axd

I do not use a regulator on one of my 6K Tanks. I used it to fill direct to my guns and tanks for 2 years BUT you must be VERY CAREFUL particularly when filling a reservoir directly on a gun. All reservoirs are tested to more than 6K BUT damage will occur to the gun that might be irreversible if overpressurized. I do use a regulator and a 6' microbore hose in order to tether a gun for extended shooting with no pressure or POI changes throughout the session

Thurmond 

@T3PRanch - That's a neat find, thanks for pointing it out. Nice to see that the regulator isn't as expensive as I had thought. One would also need a CGA 677 nipple/nut to 1/4"npt adapter (probably about $30). So $275 + $30 + $24 (for inlet and outlet gauges) = $330. So the equivalent of the Harris model 8700 regulator is indeed far less than $400 - and way less than the $464 it would cost directly from Harris Welding: https://www.harrisweldingsupplies.com/harris-model-8700-4500-677-argon-helium-nitrogen-ultra-high-delivery-pressure-regulator

So it's a $330 sunk cost for a reg with inlet/outlet gauges or as little as about $300 without the gauges for the regulator. And as @T3PRanch points out, you can do it without a regulator - but I'd nevertheless recommend putting one on a 6K tank. For me, being able to control the line pressure with a multi-turn knob just somehow feels safer. Just my $0.02 - not claiming to have the right answer, just sharing what I did.

I have a question about the nitrogen thats in the tank. Is it like the liquid nitrogen that the dermatologist uses to treat warts or is it just in a compressed gas form.

 Brian Liquid nit. comes in a 10lb to 600-700lb it is contained in a special tank ,your 6k nit is gas form. The only other tanks that have liquid in them is co2 & acet. For the noobs use the right reg.for these high pressure tanks, its nothing to mess with. do not attempt to use without the ( PROPER GAUGE).Before you turn the tank on release the handle or nob that controls the outlet pressure.gauge should show( o pressure)when you turn the tank on stand to one side not in front of the gauge & turn it on slowly then you can adjust pressuse. when your done turn tank off release all pressure from gauge then turn out pressure control nob. make sure tank is attached securely to wall & if you have kids around take the gauge off & put the steel cap back on. 
just my 2 cnts

Before I got a compressor I was also getting my SCBA refills from a 6000 psi Nitrogen tank in a lab. Its a great source of really dry 'air' for a PCP, and if transportation/refill costs are reasonable (and you can get a low cost CGA 677 regulator) its a great way to go, and will provide much cleaner air than one of the numerous low cost compressors flooding the market (for which typically you need to invest in an after market molecular sieve filter to trap oil and moisture before it gets into your gun).

One thing not mentioned here: The 6K tanks are unbelievably heavy, something to bear in mind if you need to move it after its delivered. 

As for regulators: No disrespect intended @T3PRanch but I would never take the risk of trying to fill directly from a tank, without a reducing valve (i.e. 2 stage regulator). Its too dangerous for my comfort level.

I live a bit north of Sacramento. I have called and went to Airgas and others looking to get this nitro set up in 6000 psi. They think I am freakin nuts or a bomb maker dunno which for certain!
All of them use a fill facility in Sacramento. Next thing is to go visit them I guess.
Gotta love California, maybe not

@2D1C- I lived in Cali for 20 years and worked with high pressure gases a fair amount while there - you'll probably have some stringent anchoring requirements to meet local earthquake codes. In Pasadena where I was, the codes were *very* stringent - we used to have two u-shaped braces made of 1 5/8" unistrut channels anchored to the wall (eg, cinder block anchors), one at a height within 18" of the top of the cylinder and one at a height 12" - 18" from the bottom of the cylinder. Closed-link steel chain had to hold the cylinder into the unistrut channel - no nylon webbing straps or s-links. And the lab safety guys would come by unannounced and make us take any cylinder improperly anchored, remove the regulator and cap the tank off then lie it on the ground with two hard rubber wedges blocking it up against the wall. I was repeatedly told horror stories about the 1971 Sylmar earthquake when a bottle got knocked onto its regulator and became a rocket that went through two lab walls. Not sure if that was true, but I did twice have regulators or fitting seals at the regulator blow out on me under 4000+ psi of pressure. My daughter would call those moments "jump-scares".

"prfssrlee"I was repeatedly told horror stories about the 1971 Sylmar earthquake when a bottle got knocked onto its regulator and became a rocket that went through two lab walls.

Click to expand...

I've been told the earthquake story as well, I guess that gets shared quite a bit! I've also heard the stories where a tank falls from the delivery truck while being moved, lands in a fashion where the valve separates from the tank and then tank rockets into building/car/across the street.

I've never seen it with my own eyes, but I have zero desire to do so...heh