Filling airsoft gun with propane bottle problems?

[mds131s]

I am using the propane bottles that are designed for propane torches for sweating pipes etc. They are the ones you can buy at the hardware stores and wal-mart. I am having problems getting them to fill my airsoft magazines full. When the tank was new it work awesome but now that it is about half gone it seems like I can only shoot about 3 shots before the magazine is empty after filling them with that bottle. Any suggestions I hate to waste all of that gas and use a new bottle all the time?

[Jeff686]

Your solution is to use two bottles. Just like some people do with their oxygen tanks for flying.

The bottle has lost some pressure, but still has a lot of gas in it. However, the airsoft needs more pressure than the gas bottle can provide.

Get a 2nd bottle. Fill the airsoft with the old bottle first, bringing it to a medium pressure, then top it off with the newer high pressure bottle. You'll get more useable gas from the old bottle, and the new bottle will last longer. When things stop working, buy a new bottle, and rotate out the oldest.

This method may work better on an empty airsoft magazine. In the middle of an airsoft session, the magazine is already partially pressurized, so the 1st bottle may only add a little gas.

Make sense?

Edited January 23, 2009 by Jeff686

[JimInFL]

Guys please correct me if I'm wrong, but I believe you'd get the same symptoms if you were filling your mags without turning the gas bottle upside down while filling - correct ? Wouldn't you get all gas and no liquid until the pressure became low ? Seems like I read this somewhere once. My apologies if I'm incorrect about this.

JimInFL

[Rocket35]

I have experienced poor performace when using regular propane. YMMV

[Jeff686]

Guys please correct me if I'm wrong, but I believe you'd get the same symptoms if you were filling your mags without turning the gas bottle upside down while filling - correct ? Wouldn't you get all gas and no liquid until the pressure became low ? Seems like I read this somewhere once. My apologies if I'm incorrect about this.

JimInFL

No, you are correct.

Now I'm wondering if the 2-bottle approach would work the same. O2 is not liquid when you do the 2-bottle trick.

Is the internal pressure of the LP bottle more constant, even as the volume of propane decreases? As the material is removed from the bottle (liquid or gas), the pressure drops, but the lower pressure allows more LP to vaporize and increase the pressure to equalibrium. So, the internal bottle pressure should be reasonably constant until all the liquid is used up. I'm an EE, not an ME. Am I thinking about this wrong?

[mds131s]

I have experienced poor performace when using regular propane. YMMV

What do you use instead of the regular propane.

[mds131s]

Guys please correct me if I'm wrong, but I believe you'd get the same symptoms if you were filling your mags without turning the gas bottle upside down while filling - correct ? Wouldn't you get all gas and no liquid until the pressure became low ? Seems like I read this somewhere once. My apologies if I'm incorrect about this.

JimInFL

No, you are correct.

Now I'm wondering if the 2-bottle approach would work the same. O2 is not liquid when you do the 2-bottle trick.

Is the internal pressure of the LP bottle more constant, even as the volume of propane decreases? As the material is removed from the bottle (liquid or gas), the pressure drops, but the lower pressure allows more LP to vaporize and increase the pressure to equalibrium. So, the internal bottle pressure should be reasonably constant until all the liquid is used up. I'm an EE, not an ME. Am I thinking about this wrong?

So do I need to fill the mag with the bottle upside down?

[Rocket35]

So do I need to fill the mag with the bottle upside down?

Yeah- when all else fails- follow the instructions.

I use the gas manufactured for airsoft guns.

[Joe4d]

Is your propane bottle outside in an unheated garage ? Try putting it in a pale of hot water for a few minutes.

[Duane Thomas]

I have experienced poor performace when using regular propane.

rocket35, could you be a bit more specific? What sort of poor performance?

[Flyin40]

+1 on filling it upside down. Also if you use propane make sure you lube with silicone.

Flyin

[AWLAZS]

I have experienced poor performace when using regular propane.

rocket35, could you be a bit more specific? What sort of poor performance?

When I use regular propane. The gun works great for the first half a bottle slowing down just a little. Once you get to a half the gun really starts to operate like a new guy is running the reloading press. The gun does not cycle well etc.

Edited July 9, 2009 by AWLAZS

[MT_Bear]

I have a Tokyo Marui pistol and I use the compressed dusting spray (HC134a) that is used for blowing dust off of keyboards and equipment. It is available at Costco in very affordable 6 packs. The place where I bought the airsoft pistol recommended it. They also have a kit from Airsoft Innovations that had the silcone oil and adapters.

Here is the link for the description of the kit: http://www.airsoft-innovations.com/GunGas.html

[Matt Griffin]

A few points on this:

1. At the same temperature, and if any liquid propane remains in the bottle at all, the bottle will be at the same pressure as when you bought it. The liquid propane will become gaseous until the space in the bottle is saturated, a point determined by temperature.

2. You must fill the mags upside down, so that liquid flows into them, rather than gas. With gas (and without a regulator) every shot will decrease the pressure of the supply. With liquid, there is much less reduction, represented by cooling of the magazine when the liquid evaporates to fill the new pressure gap, causing a decrease in temperature.

So, a better solution than two bottles is two mags. Shoot one, then the other so that the first one can warm up. I've found that in serious practice, however, I have to quit after ten minutes or so as both mags are too cold to continue. I haven't experimented with warming them back up manually, but that should work. Maybe with a bowl of warm water, if you can keep it away from the springs.

H.

[Duane Thomas]

I have a Tokyo Marui pistol and I use the compressed dusting spray (HC134a) that is used for blowing dust off of keyboards and equipment. It is available at Costco in very affordable 6 packs. The place where I bought the airsoft pistol recommended it.

My understanding (and I could stand to be corrected on this) is that 134a is less powerful than Green Gas or propane, thus is really the only appropriate choice for something like an unmodified (i.e. plastic slide) Tokyo Marui. Green Gas/propane will batter a plastic slide gun and accelerate wear way too fast for dedicated practice.

But will 134a operate a metal slide gun reliably is what I'm wondering. (?)

[kevin c]

A few points on this:

1. At the same temperature, and if any liquid propane remains in the bottle at all, the bottle will be at the same pressure as when you bought it. The liquid propane will become gaseous until the space in the bottle is saturated, a point determined by temperature.

+1

2. You must fill the mags upside down, so that liquid flows into them, rather than gas. With gas (and without a regulator) every shot will decrease the pressure of the supply. With liquid, there is much less reduction, represented by cooling of the magazine when the liquid evaporates to fill the new pressure gap, causing a decrease in temperature.

+2

So, a better solution than two bottles is two mags. Shoot one, then the other so that the first one can warm up. I've found that in serious practice, however, I have to quit after ten minutes or so as both mags are too cold to continue. I haven't experimented with warming them back up manually, but that should work. Maybe with a bowl of warm water, if you can keep it away from the springs.

+3, with the observation that if you keep the unused mags in your pants pocket, they will stay warm. Put them on your belt if you want to to reloading drills (I don't trust my mags to hold up to that kind of beating) right before actual use. Pop them back into your pockets once in a while and you'll get more full power (is that an oxymoron?) shots per charge with less wait time. Works best with three or four mags.

eta: I've thought about but haven't done this, but it ought to work - one of those soft pocket warmers, much warmer than body temperature. Set your mags on that and they should be plenty warm.

Note to newbies. Propane and green gas (which is the same but with a different less unpleasant odorant) are heavier than air and flammable. Don't practice in a closed area with an open flame source such as a water heater or furnace.

Edited July 9, 2009 by kevin c

[MT_Bear]

I have a Tokyo Marui pistol and I use the compressed dusting spray (HC134a) that is used for blowing dust off of keyboards and equipment. It is available at Costco in very affordable 6 packs. The place where I bought the airsoft pistol recommended it.

My understanding (and I could stand to be corrected on this) is that 134a is less powerful than Green Gas or propane, thus is really the only appropriate choice for something like an unmodified (i.e. plastic slide) Tokyo Marui. Green Gas/propane will batter a plastic slide gun and accelerate wear way too fast for dedicated practice.

But will 134a operate a metal slide gun reliably is what I'm wondering. (?)

You're correct Duane - My TM is the plastic slide and the instructions from the vendors (since I can't read the @#$%& japanese instructions) warn against using propane or green gas. I'm not sure how reliable the HC134a is for a metal slide pistol.

[Duane Thomas]

Thanks for the info.

[Jadeslade]

Propane and green gas (which is the same but with a different less unpleasant odorant)

Good point about the gas being flammable. Green gas has silicone in it, so that the gaskets and seals remain pliable(Air Duster is the brand I'm using-from AirSplat.com)

[Duane Thomas]

Good point about the gas being flammable. Green gas has silicone in it, so that the gaskets and seals remain pliable(Air Duster is the brand I'm using-from AirSplat.com)

I believe that Air Duster is not Green Gas, nor is it flammable. Air Duster is nonflammable 134a.

[mcoliver]

Slight OT. On plastic slides: My TM 5.1 open gun has a plastic slide with a 150% recoil spring, fed green gas since day 1 and has consumed about 10 packs of BBs (around 40K+ not including those sessions where I didn't use BBs.) No breakage so far. I do keep two spare plastic slides just in case.

Also, +1 on adding silicon when using reg propane to save those o-rings.

[kengrant]

Warm bottle---- cold mag----fill upside down-----works everytime.

In warm weather I can get over 6,000 shots from a Coleman Propane Bottle.

When it is cold I get less but almost as much using the above method.

[Flatland Shooter]

As you shoot, the gas within the magazines expands and cools the magazine. The cooler the gas, the less expansion will take place. If you could keep the magazine warm, you will get maximum benefit from the amount of gas in the magazine.

To extend the number of shots per magazine, I'll shoot 10 rds or so and switch magazines. That allows each magazine to warm back up and results in the extra shots.

For an extended session, I place the loaded magazines under a heating pad to speed things up.

Bill