AirTank flow restrictors

Prior to purchase I liked the idea of an air flow restrictor in the Omega tank's hose connector. It is a removeable allen head set screw threaded inside the DIN300's air hole. In actual use IMO the restrictor is more of a liability than a benefit. It is much easier to operate the tank and get accurate air flow control by managing the tank valve slowly without the air restrictor. The restrictor blocks air flow and causes the gauge needle to jump up to the tank pressure level instantly since a microbore hose instantly equalizes to the tank fill pressure. This makes me react to close the valve when the fill pressure reads above the intended rifle fill pressure. Gauge pressure increases without a restrictor but quickly stops when it meets the back pressure from the PCP's internal check valve. A restrictor blocks air flow from both directions and is the cause of gyrations in pressure within the hose that are disconcerting. The bottom line is that the tank valve is easier to control and the fill process operates smoothly without a restrictor.

I discovered Omega fill sets at an airgun show and was impressed by the extremely flexible 3' fill hose that can be bent sharply without causing damage to the hose coating. Most plastic cover microbore hoses crack and split if the hose gets bent sharply. I also prefer the push button air release instead of a thumb screw bleed valve. The delrin tip on threaded bleed valves eventually leak from repeated usage. The button style release may not be for everyone as it takes more effort to push down to depressurize the fill hose.

Over the years I've owned many tank sizes and brands. I bought my first tank set 18 years ago before lightweight carbon fiber tanks became popular. It was a 100 cf aluminum scuba tank that only held 3000 psi but was a brick weighing 40 pounds. The whole setup cost a little over $200 but it was a PITA to lug around. The best advice I can give to newbies is to buy a new name brand 4500 psi carbon fiber tank set instead of trying to get by on the cheap with a scuba tank. You won't regret it.


 
I also have a Omega tank, 100cf, and so far I’m liking it. The push button release works for me but others might have some issues with it. I don’t have a compressor yet, as my local deal didn’t work out. What makes this a interesting topic to me is the flow restriction and it’s effects on filling your tank from a compressor. Other member has posted, and maybe he will respond, that maybe the restrictor could cause issues filling. My tank was filled from a cascade system at a dive shop and there were no issues. Here’s my question for future use. Should a guy pull out the restrictor when filling the tank from a compressor and the put it back in to fill the rifle? Thanks for the great topic.
 
Maybe I'm looking at this all wrong but I like the idea of the flow restrictor, especially on small pistol reservoirs. I look at the pistol gauge and not at the tank gauge. Even with the restrictor in place, my GW fills my pp700 and HW44 reservoirs FAST even with great care in opening the valve. Wouldn't want it any faster IMO. I could see how it might be a hindrance to filling the tank but I'll keep it for filling the reservoirs.
 
I also have a Omega tank, 100cf, and so far I’m liking it. The push button release works for me but others might have some issues with it. I don’t have a compressor yet, as my local deal didn’t work out. What makes this a interesting topic to me is the flow restriction and it’s effects on filling your tank from a compressor. Other member has posted, and maybe he will respond, that maybe the restrictor could cause issues filling. My tank was filled from a cascade system at a dive shop and there were no issues. Here’s my question for future use. Should a guy pull out the restrictor when filling the tank from a compressor and the put it back in to fill the rifle? Thanks for the great topic.

pmg, Definitely remove the restrictor insert if you're filling your tank using the Omega hose. I've removed my restrictor screw permanently because of reasons I stated in my post above. I find the fill gauge pressure easier to control with the tank valve alone and no restrictor blocking air flow in either direction. 

@Bandg, I don't fill pistols so that isn't an issue for me. The check valve in a rifle or pistol slows the air flow sufficiently for me to control air flow using the tank valve alone. I am careful and open the tank valve very slowly on a fill.
 
I also have a Omega tank, 100cf, and so far I’m liking it. The push button release works for me but others might have some issues with it. I don’t have a compressor yet, as my local deal didn’t work out. What makes this a interesting topic to me is the flow restriction and it’s effects on filling your tank from a compressor. Other member has posted, and maybe he will respond, that maybe the restrictor could cause issues filling. My tank was filled from a cascade system at a dive shop and there were no issues. Here’s my question for future use. Should a guy pull out the restrictor when filling the tank from a compressor and the put it back in to fill the rifle? Thanks for the great topic.

pmg, Definitely remove the restrictor insert if you're filling your tank using the Omega hose. I've removed my restrictor screw permanently because of reasons I stated in my post above. I find the fill gauge pressure easier to control with the tank valve alone and no restrictor blocking air flow in either direction. 

@Bandg, I don't fill pistols so that isn't an issue for me. The check valve in a rifle or pistol slows the air flow sufficiently for me to control air flow using the tank valve alone. I am careful and open the tank valve very slowly on a fill.

I do fill pistols (2) and I also open the tank valve very carefully. And both pistols I mentioned have jumped VERY quickly to full even with the restrictor. I don't really disagree with your basic view at all, but I feel better with the restrictor than without it myself. If not for the pistols it might be different. I think everyone is careful right up to the point of an accident. Let's hope no one has any.
 
I know the Brocock QC extension has a slow-fill reducer that can be removed. I hate to advertise one company over another but one thing I think is fantastic is the Ninja EZ valve. It's the best of both worlds and fit one of the requirements I had -- unrestricted fill/input, restricted output. It does this via a Foster fitting on the neck of the valve with a check valve which bypasses the valve assembly. This means that filling is made easy and there is no compressor hose/valve pressure mating dance -- the check valve opens when the hose pressure exceeds the bottle pressure.

A member here has the SCBA to EZ Valve adapters up in the classifieds and if not for my 90 cu-in tank that already meets my needs I'd pull the trigger on it.

I think the important thing here is regardless of the setup, unrestricted fill is important to avoid unnecessary back pressure on the compressor? Everything outside of that is just additional benefit depending on the use case. Now that I think about it though, I was using the Brocock QC extension with the restrictor in place and it didn't blow up my compressor. Hmm, maybe I got lucky or maybe it doesn't matter. I had about 9 bottle fills using the restrictive QC extension. Now all fills are done with a unrestricted micro hose extension off the 300 DIN to QC adapter.

Now I'm irked at myself for using the QC extension which was restricted as long as I did, knowing better, and not having even considered it.


 
Indeed, for context, the 9 fills I did were top-offs from 3200 PSI to 4500 PSI on the LC-110 and the average fill time was less than 5 minutes. For the FLIR images I did 0 PSI to 4500 PSI through an unrestricted microbore hose. I only did top-offs with the restricted Brocock QC extension.

Absolutely food for thought and I'm eager to hear from those who may be able to substantiate my belief/assumption or negate it; either is truly appreciated.

All my initial reading I did when I selected the EZ valve pointed to unrestricted fill as being a "must" especially for higher CFM compressors to reduce back pressure. Thankfully I didn't bork stuff (yet) and I've since removed the restriction in the QC extension today. I have no experience with the GW tanks so I won't opine either way but will be watching the thread to learn.