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Joe Friedrich
12-26-2007, 08:09 PM
Why does one use compressed air from Scuba shops compared to lets say a welding supply house?

I will assume one uses a different compressor over the other.

Thanks.......Joe

DonMatzeder
12-26-2007, 08:39 PM
I don't know any welding houses that sell compressed air. They do sell high presure nitrogen which works fine but comes at 6000lbs so be VERY careful filling your gun. Scuba is also dry and debris free (certified for breathing). This protects your gun from rust and clogged valves.

EDIT!!! Joe as an old racer, I'm sure you know this but for the others reading this...Nitrous oxide and Nitrogen are two different things...do not use nitrous oxide in your airgun....

Joe Friedrich
12-26-2007, 10:04 PM
Don, Thanks. We used the big bottles from a welding house filled with nitrogen using a regulator to fill the bottles on the paint ball guns many years ago. There are welding suppliers here that do furnish Compressed Air.

Without talking to them more, i don't know what kind of compressor they use, and how they filter the air if any. I did not think about the possibilities of contamination, Thanks.

Don, if one was looking to purchase a compressor, what would you recommend?

Thanks.....Joe

DonMatzeder
12-27-2007, 02:47 AM
Do a search for Alkin or Airetex (American importer, Bruce Dodson). I had one for several years and it gave very good service. Not a 100% duty cycle commercial machine but very solid. About 2500$ On a budget, Mil Surplus flame thrower compressors but you have to be willing to build it yourself...seperators, motor, gearing. high presure tubing...I really wouldn't reccomend that route for someone just getting into this.

http://www.airetex.com/w31.html

Dave Shattuck
12-27-2007, 09:33 AM
Joe.

My advice; call Allen and get his opinion! He's been doing this for years as one of the top airgunners in the world and would know more than most anyone else on the subject, plus, for some reason I'm assuming he fills his own tanks. I may be wrong, but that's at least where I'd start.

Dave

Joe Friedrich
12-27-2007, 02:08 PM
Don Thanks, you have a good point. Was curious so i searched last night and found compressors from the paint ball sites, good reading and information. They are pricey and you are right about spending that kind of money just starting out.


If there is enough interest here, its something to look at down the road.

Dave, Thanks and will give Allan a call.

Fred J
12-27-2007, 03:01 PM
If a club were to furnish a compressor so shooters could refill their Scuba Tanks, or the Cyclinders, they would also have to do the same for CO2 owners. I don't think any club can afford that.

Dave Shattuck
12-27-2007, 03:17 PM
Stopped by at the only Dive Shop within 25 miles of here this P.M. and had a chat. They said that their fill capabilities only went up to around 3400 psi, but gave me the number for a Paintball & Laser Tag Center that is just opening in the area and said it was their understanding that the new place would be able to go all the way up to the 4500 psi for filling Carbon Fiber tanks to the max. In fact, I guess the compressor was just being delivered today.

If you're running with a Carbon Fiber tank and needing the 4500 psi fill-ups, look around your areas to see if there is a Paintball facility rather than Dive Shop.

Dave

DonMatzeder
12-27-2007, 03:51 PM
CO2 is really quite easy. Any soda pop deliverery truck delivers canisters of co2 to their customers every day. I paid $20 dollar deposit (one time cost) and $11 for an exchange (about once a year). This tank will not have a syphon tube in it so you need to turn the tank on its top to fill your gun with liquid. I dealt with the truck driver but you could work the same deal with any local soda shop (they stock several at all times so they can exchange when one runs out).

tim
01-01-2008, 06:00 PM
Don, if you start to read some of the English mags and look at Field Target reports you will see Co2 is not used for lots of reasons in high quality systems. Hint... there's a reason all that vapor exits the bore of a paint ball gun and it ain't good if you're trying to put pellets in one hole.
Joe, Anshutz and Steyr make compressors as well, they're not cheap, but you can get them.
I'll tell you though, for anybody in reasonably close proximity to a dive shop the SCUBA tank approach works well, you can get one hell of a lot of fills to around 3000psi on a gun, if your a fanatic you're talking about a trip every 3-4 weeks.

DonMatzeder
01-01-2008, 06:18 PM
The reason you see that white mist is because they are poorly designed and tuned. Most have been stepped on to increase power by someone that doesn't understand the valve. Reading Brit rags won't get you any good information as there mind set about their power limit and the power of the State to come down on them for modifying something has kept them in 20 year old technology. They have some great shooters but US equipment is vastly superior to theirs. The USFT is designed to work in a presure range of from 1700 down to 1200 PSI. It could be valved to work on CO2 and deliver the same 20fpe...probably more consistently than now with a capacity for 5 or 6 hundred shots between fill ups. The only down side would be temperature sensitivity. CO2 is not a bad thing, it just has some ground rules that keep it from working for our purposes. Horses for courses...

Edit: I don't think Anchutz or Steyr maike a compressor but rather market under their name a motor driven bicycle type pump that will fill a gun but will not fill a tank. If you hook it to a tank, it would take two days to fill and the pump would burn up before it got the job done.

Wilbur
01-10-2008, 10:41 PM
The nuclear plant where I was employed had a breathing air compressor that filled to 3000psi - dried and filtered. The compressor skid was about six feet square and the dryers were banded to the wall above the fill station. A daily checkout of the system was on the list of things to do - checkout and fill any empty bottles. Checkout consisted of oil level, starting the compressor, verify that it shutoff at 3000psi and then fill the empties. It was a four stage compressor and the stages looked like a wedding cake. I started it up and realized that I forgot to check the oil first. Rather than shut it off, I leaned over the components reaching for the dipstick at the exact moment the final stage head gasket blew out. It didn't go quietly...sounded like dynamite and I was sure I was dead. Didn't actually have to change underwear but I did go check.

cumbo
01-11-2008, 04:16 AM
Air from dive tanks is dryer than air from pumps due to the water traps on the filtration system, so you will have less moisture being pushed through you firearms, where compressed air not for breathing purposes will not have this additional filtration. Most dive compressors these days are capable of 5000psi fills if you adjust the blowoff valve. Cost for small dive compressors are approx $2500 for a coltri-sub or approx $3000 for a bauer and with both of these units you would want to fill a dive tank and decant from it. My advice get the biggest dive tank you can with approx a 3500psi working pressure and visit a dive shop when you need to fill it. My steyr air pistol was easier to fill than its co2 predecessor due to not having to freeze cylinders prior to filling, and not having to weigh cylinders and it did not giving me any grief in hot weather and the dozen+ dive tanks I have at home made it easier to.

Marmot_Militia
01-11-2008, 10:46 AM
My advice get the biggest dive tank you can with approx a 3500psi working pressure and visit a dive shop when you need to fill it.

I'd have to disagree with the 3500psi suggestion, get one rated to 4500 (steel or CF) you will get way more 3000psi fills. The metal tanks are around $170 from airhog.

Regards,
MM

tim
01-11-2008, 09:06 PM
Dive shops generally will not put much more than 300psi in a tank do to liability

Keith S
01-13-2008, 09:43 PM
As a newbe that may get started in Air Gun BR, I have a couple of questions. How much air in Cubic feet or cubic in. does an air rifle hold on a fill and at what pressure (psi).

DonMatzeder
01-14-2008, 06:48 AM
Every gun is different. Size of tank, opperating pressure, efficiency and output all play into the equation.

Marmot_Militia
01-16-2008, 09:55 AM
Dive shops generally will not put much more than 300psi in a tank do to liability

If the tank has current hydro certification there is no liability. I believe the trend in diving is to go to 4500psi tanks for longer bottom time.

Regards,
MM

Keith S
01-16-2008, 10:25 AM
The psi has nothing to do with bottom time. Bottom time has to do with how much cubic ft. of air your tank will hold. Back in the late 70s when I was diving I used double 50 cubic ft. tanks for a fill of 100 cubic ft at 1800 psi

DonMatzeder
01-16-2008, 10:59 AM
The higher the presure, the more cubic feet of air at one atmosphere can be put in the tank. Many dive shops do not want to invest the money in a new compressor that will go to 4500 psi. Most paintball shops, have newer compressors that will go that high. Check your local area and see what is available.

Marmot_Militia
01-16-2008, 01:04 PM
The psi has nothing to do with bottom time.

As Don said, yes it does. More pressure in the same area equals more volume.

Cubic feet (or inches) are measured at 1 atm. An 80in^3 tank olds 80in^3 of air at 1 atm. If you have 200atm (bar) in a 80in^3 tank there will be twice the volume as 100bar in a 80in^3 tank.

As far as rifles go, the Theoben E-type are exceptional rifles for the price. I've shot several with a dealer friend of mine and they are freekishly accurate out to 60 yards (longest shooting of the day). If I wasn't tickled to death with my EV2 I'd get one for sure.


Regards,
MM

Keith S
01-16-2008, 01:30 PM
How many cubic feet of air does one of the 4500psi tanks hold?

Marmot_Militia
01-16-2008, 02:35 PM
Tanks come in all sizes. Check http://airhog.com/cf_tanks.htm.

An 80ft^3 tank rated at 4500psi will hold 80ft^3 of air at 4500 psi.

An 80ft^3 tank rated at 3000 psi will hold 80ft^3 of air at 3000psi

BUT, the 4500psi tank is smaller, OR, if you prefer,comparing equal size tanks, tanks that are of the size that hold 80ft^3 at 3000 psi will hold 120ft^3 if rated for 4500psi.


Regards,
MM

Fred J
01-16-2008, 02:52 PM
How many refills will a tank of this size and pressure supply? Seem like pressures that high could be dangerous when rolling around in the back of your pick up or trunk. Maybe I'm just used to CO2 and just filling at home from my supply tank I keep there.

Marmot_Militia
01-16-2008, 04:26 PM
http://www.airgun-hq.co.uk/AirgunTools/tabid/54/Default.aspx


Regards,
MM

DonMatzeder
01-16-2008, 07:51 PM
I had a neck O ring (between bottle and valve) blow on a fresh 4500lb tank in the floorboard of my pickup once..while driving down a freeway with heavy traffic...it was exciting for a while. I got the window open and it took about 10 minutes after I got to the shoulder for the thing to bleed down all the way.

Fred J
01-16-2008, 08:41 PM
How long did it take you to find your dufflebag?

DonMatzeder
01-17-2008, 07:00 AM
Quite a while...you don't move too fast walking stifflegged. The thing I learned from this was that the cheap way is not always the best way. I had cut a deal with the local fire department to fill the tank. This was before I had bought my compressor. The first fill I was present for and I showed them how to hook it up and fill it. The second fill, I was told they were busy and to leave the tank and they would get it later. When I returned, it was full and I thought all was well. After the blowout, I did some questioning, and the fireman said that he could not understand it, he had removed the valve and "inspected" the tank himself. He had, I'm sure, pinched the O ring when he reinstalled it.

fx77
01-21-2008, 03:27 PM
My local dive shop will not fill a tank unless you provide proof of Diver Certivication. I explained it was for air rifle and they could not care less.
Fortunately I went home and got my card from 1970 proving certification and they had never seen one so old (the card that is).

Joe Friedrich
01-27-2008, 06:17 PM
Thank you gentlemen for all the information.

Joe

DonMatzeder
01-27-2008, 06:33 PM
If a dive shop declines filling you tank, try to give him this waiver..
http://www.airhog.com/pdf/waiver.pdf

dbaker
02-05-2008, 08:42 PM
I didn't see anyone mention your local firestation or firehouse supplier. I have a firehouse supplier in my area and he fills my 4500psi carbon fiber tank for as little as $5.00. Check um out. Nitrogen can be used but i don't think the pressure is great enough. The 4500 tank is great.

Kurt Westfall
02-22-2008, 03:30 PM
I shot air in the old BR50 days. If I remember right we would fill the rifle to 2400 psi, that is were the best accuracy was. I have a 100 cu ft tank and I shot the nationals at St Louis the last year BR was there, it lasted both days. Tank pressure is around 3200 psi. You can get around 25 good shots per fill and it will take a few sighters to settle down after a fill. Used 10 grain round nose pellets and sprayed them down with Slick 1 Lube.

cntryboy1289
03-11-2008, 02:39 AM
I am coaching air rifle in our local 4H chapter and I recently bought some new CO2 rifles for our kids to use. I had been planning on just having the local welding supply house to refill them for me but lately decided on buying an Avanti adapter to hook up to my CO2 tank for my MIG welder.

Is there anything that anyone can tell me other about other than having to turn the tank upside down to fill the tanks? Do they need to be weighed or can I just use my gauge to fill them to the required psi?

Also, now that I found this particular post, since I am a retired fireman, I have access to the compressors for filling the SCBA's. What would be required to change the Avanti rifles over to run on compressed air?

Thanks for any help with this issue.

Jeff

hoser
03-11-2008, 07:20 AM
Also, now that I found this particular post, since I am a retired fireman, I have access to the compressors for filling the SCBA's. What would be required to change the Avanti rifles over to run on compressed air?

Thanks for any help with this issue.

Jeff

Jeff,

I also have a few of the Avanti rifles from a junior program I used to run, and I don't think they can be converted. The head pressure of liquid Co2 is aound 700-900 PSI (if I remember correctly, depending on temp of container and contents) and filling a Avanti tank with 750-900 PSI air would yield very few consistent shots.

The Avanti does not use a "regulator" but relies on Co2 "head" pressure for somewhat consistent pressure. As the head pressure drops, the liquid Co2 gassifies and returns the pressure to near former level. BUT as the Co2 boils off, it also reduces the temperature of its container (that's how your airconditioner works), thereby further lowering the head pressure. Kinda of the chicken/egg syndome.

But with air at the same pressure, you are not replacing the lost pressure through gasification, therefore each shot would be a lower velocity.

High end PCP rifles use regulators set around 1000 -1200 psi. So, until the tank pressue falls below that, you have a consistent velocity.

cntryboy1289
03-11-2008, 01:14 PM
Thank you very much for the information. I had been very curious about it before I found the post and didn't have anyone locally to ask. If you or anyone else could help me with the proper procedure for filling the CO2 tanks, that will be greatly appreciated as well. I will be using my CO2 tank from my MIG welder to refill the tanks using the Avanti refill kit.

I think if I remember correctly that the guy that fills my son's paintball gun tank has to weigh it on scales. Is that correct by chance?

hoser
03-11-2008, 03:11 PM
I think if I remember correctly that the guy that fills my son's paintball gun tank has to weigh it on scales. Is that correct by chance?

Well...sort of.

2 things to keep in mind:

#1 He probably sells CO2 filling by weight, therefore he weights them for pricing

and

#2 If you were to be able to get the cylinder completely full, and if the cylinder temperature were increased, the blow-off seal would probably pop.

Therefore, it's best to slightly fill the cylinder, then bleed it off to cool the cylinder. Then fill it to your recommended capacity (Fl Oz of Co2). I don't remember what the tanks are rated for.

Having said that...I filled them with the cylinders at room temp, that way some of the liquid CO2 would boil off enough during filling that you couldn't get "too much" in them to pop the seal if the tank was heated (closed car, in the sun, etc.)

I have a tank with a dip tube so I didn't have to fill upside down.

Good luck.

cntryboy1289
03-16-2008, 02:07 AM
thanks, sorry was gone for a few days. I talked with Daisy and they told me what you just did.

Jeff