Coleman Xtreme Canister – claims usable to -27C/-16F

Interesting!

I have not seen one yet. Note that the canister is same distinctive shape as the CV 300 canister but with a screw thread valve instead (Coleman own Campingaz – or is it the other way around?).

-27C is possible if there is enough propane in the mix – it would need to be 40% propane, and you would need to use it inverted to maintain that operating temperature, but quite feasible.

As Stuart said. (Yes, Coleman owns Campingaz.)

All they have to do is to reduce the diameter slightly and strengthen the steel slightly, so that the canister itself can take a somewhat higher pressure. Then they can use a gas mix with a higher vapour pressure and still pass DoT regs.

I think it is a marvelous idea!

Cheers

The specs on the link above show the canister weight of 121g (351g – 230g) which is 10-15% lower than the ones I have weighed of other brands.

I have used Jetboil and Primus canisters at -25c on an inverted stoves with no issue at all. I just keep the gas can warm until use and put it on a piece of foam when in use.

Has worked many times winter camping in Michigan. I use new canisters in winter and then use the half empty ones for 3 season use.

Hi Stephen

I use new canisters in winter and then use the half empty ones for 3 season use.

IF you used the canister consistently inverted, then the gas composition should not have changed very much during use. You should be able to keep using that canister at -20 C until it is empty. That was the norm for the old Coleman Powermax canisters: they could only do a liquid feed, and we used them till MT.

Cheers

Thanks for info Stuart and Roger.

If that is a 60/40 mix, or even 70/30, that would be great, but we’ll never see it here.
The best we can get here in Canada and the US(?) is an 80/20 mix.

I’ve used an MSR 80/20 canister upright with a non-winter remote canister stove before I learned the difference, and it worked,but I bet I had burned off most of the propane in that process.

Brad, Jetboil claims to have 25% propane and 75% iso-butane in their canisters. You only get 100 gm. of fuel in the small canisters though, unlike the 110 gm. that are in the MSR, Snow Peak, and other common “4 oz.” canisters. I contacted Jetboil to ask why, and they said it was due to the increased partial pressure of the extra propane. That sounded fair, until I checked out the various 220 gram canisters. JB has a wee bit more fuel in theirs than do MSR and Snow Peak. Maybe the 220 gm canisters are built stronger?

Something I would like to add about fuel options–Olicamp has come out with their own version of canister fuel, which appears to be identical to Jetboil’s, only cheaper. 25% propane/75% iso-butane, identical canisters, etc. I am testing some that I picked up on sale, and I am waiting for some +15* F weather to do a head-to-head cold weather comparison of the JB and Olicamp fuels. My initial impression is that they are filled by the same company in Korea, and that they will perform the same. We’ll see…

You only get 100 gm. of fuel in the small canisters though, unlike the 110 gm. that are in the MSR, Snow Peak, and other common “4 oz.” canisters. I contacted Jetboil to ask why, and they said it was due to the increased partial pressure of the extra propane. 

Sound like total rubbish to me. I suggest the person saying that actually had no idea what they were talking about. Perhaps the canister is slightly smaller?

Cheers

I’d also wager that 100g vs 110g isn’t going to make any difference at all.

Aren’t the canisters the same ones made by the Korean company (Tae-yang) that makes all the others?

Many times I have refilled canisters with more than 110g of N-butane but the VP is MUCH lower than propane.

Perhaps the canister is slightly smaller?

Interesting. Now I’m curious.

One thing I see right away at my local retailer is that MSR, Optimus, and GSI 110g canisters are $6.25 CDN, SnowPeak is $6.50, and Jetboil is $5.75.

I think I’ll go and pick up a 100g Jetboil canister (what’s one more?) and compare it to the MSR ones I have here.

See photo:

The plastic cap on top is identical to MSR, Primus, etc that are all made in Korea, and you can see on the lower left part of the canister ‘Made in Korea’ although it’s a bit fuzzy.

Edit to add: I suppose JB could pay a premium to the manufacturer for special tooling just for them, but that seems extremely unlikely.

What I want to know is if Jetboil and Olicamp are in cahoots somehow. Or does that Korean canister-filling company sell the same mixture to anyone that wants it, and that Olicamp is willing to reduce its wholesale price by $1? Also whether the JB and Olicamp fuels are identical (which I hope to ascertain this winter).

Also, Bob, I want to know just one more thing–what was the maximum number of grams of pure butane that you felt safe to put into a 110 gm. canister? I know that you are sensible and scientifically cautious, so I’m curious as to how far you were able to take it. If one of those canisters could safely hold say, 135-140 grams of n-butane, that would be a total game changer for cooler shoulder season outings.

Gary, IIRC the most N-butane I’ve put in was 123g. (If some of our resident experts think that’s insane, please advise!)

No problems with that, but I wouldn’t intentionally go much over that because it seems to me it needs some ‘head space’ in there to vaporize.

I have also wondered if it would be possible somehow to make a much lighter container for n-butane since its VP is so much lower than propane and isobutane…

OK, expert comment coming.

It does not matter how much headspace or empty space you leave in a fuel container, as long as that space holds fuel vapour and not air. Whether you have 1 cubic centimetre of empty space or 100 cu.cm, no matter. The vapour pressure (VP) inside will be exactly the same. Put in engineering terms, the VP is determined solely by the gas composition and the temperature. Volume simply does not matter.

In other words, the amount of ‘head space’ available is totally irrelevant – as long as there is a tiny bit. Do not fill a canister up right to the brim, such that there is no vapour space left. That would be dangerous as you might end up with no expansion volume left for the fuel to expand into if (when) it gets hot.

The (USA) DoT regulations are aimed at making the transport side of things safe. They are not meant to cover all the other aspects, but in practice they do, because they are pretty comprehensive. So most companies play it a bit on the safe side.

Could one make a lighter container for straight butane, since it has a lower VP? Yes, one could, but production economics get in the way.

Does the ‘Korean canister-filling company sell the same mixture to anyone that wants it’ ?  Probably – production economics again. Are other fuels from different labels the same? Very often, for the same reason. Do all the different brands use the same plastic caps? Probably – same reason again.

So what is the difference between a Korean filling company and a Chinese one? As far as I can see, the difference lies upstream in the fuel production line. The Korean fuel seems to be properly filtered and most of the heavier paraffins cleaned out; the Chinese fuel seems to miss the filtering and cleaning stages.They cost money after all.

If you are running an upright stove, the Chinese fuel probably works as well since all the muck and garbage stays at the bottom of the canister. It does not vaporise. But if you are running an inverted-canister stove – be prepared for great grief with Chinese fuel. The fastest block-up I have had with a new Chinese canister was ~20 seconds. Twice running.

Cheers

OK, Roger, so what’s your best guess as to how many grams of n-butane can safely be put into a standard 110 gram canister, and still be safe at 50* C? Surely more than Bob’s 123 grams, but just how much more?

Hi Gary

Dunno.

I would need to measure the volume of a 110 g canister – and I don’t have any. Want to have a go at that? Drill out the Lindal valve, weight empty, fill completely with water, weigh again.

Cheers

I might have a way to do that, Roger. Stay tuned…

OK, I’ve done it. Roger is likely asleep right now, but when he sees this he will absolutely cringe at my materials and methods. I think my results are fairly accurate, but I won’t pretend that this is a highly scientific exercise.

First off, the canister used–a Snow Peak 110 gm one from back when they were made in Japan (ah, the good old days, when an empty canister weighed just 3.0 ounces) The photo shows the empty test canister on the left, and a full one on the right (yes, I’ve hoarded a few of the lighter ones for posterity).

But this is no ordinary empty 110 gm. canister with vent holes marked for the recycling people to see. A few years ago I wanted to see what the inside of a canister looked like, so I cut the bottom off one to see what I could see.

The bottom of the lindal valve is somewhat interesting, no? But then there’s the need to close those holes to make them waterproof. I chose to employ a very high tech material for this purpose. It’s called duct tape.

To be able to set the inverted canister top on my scale, I used an empty cat food can to set it on. After taring out the cat can, the canister body (sans bottom base) weighed 49.8 grams. I  filled up the inverted canister with distilled water, and I then carefully placed the concave canister bottom on the canister body to displace the excess water. After drying the water that spilled out onto the outside of the canister body, I re-tared the cat food can and placed the canister with water on. The new weight of canister top and water was 270.0 grams.

I double checked the volume of the water in the canister by decanting it into a clean 8 oz. alcohol dispensing bottle, then pouring it into a 30 cc measuring cup. As close as I could tell, there was exactly 220 cc of water, which confirmed my earlier weight measurement. So it looks like the total interior volume of a 110 gm. canister is 220 cc, assuming that 1.0 gram = 1.0 cc of water.

OK, Roger, it’s now up to you to calculate how much n-butane Bob gets to put into his empty 110 gm. canisters with a reasonable margin of safety.

Thanks for the help!

I want to maintain the few canisters I have since they can be refilled, so now I don’t have to sacrifice one on the altar of science. :^)

I was asleep, but now I am awake (sort of, barely). I have been for a morning run, but I have not had breakfast yet. What follows must be taken in that light  :)

No, I am NOT cringing, not at all. I think Gary’s method is excellent, and quite able to deliver the measurements needed at the accuracy needed. This is not a NIST matter after all. (And fwiiw, I would do the same if I had a canister opened up like that.)

Now, the 220 cc volume is OK. The density of liquid n-butane is 601.26 kg/m3 (from the web). 1 m3 is 10^6 cc. So the mass of 220 cc of n-butane will be 220 x 10^-6 x 601.26 = ~132 g. Bob managed to get 123 g into his canister. We have a very good match here, allowing for perhaps a little bit of air trapped in the top of the canister. A few cc of air maybe?

So: how much n-butane could you safely put into a canister? Well, the official answer is that you are not permitted to refill a canister … Moving on from there into the land of hypotheticals, I would suggest that 120 g is really full enough while preserving some expansion space, and 115 g might perhaps be rather conservative. I do not think dropping down to 110 g would ever be needed for safety, but that amount would make sense for a production system wanting to stay very clear of any hazards.

My 2c.
Cheers

Good job on the measuring and math, gents.

I was pretty sure a little overfill would not be a problem with n-butane. When I shook the can there was still enough room for it to slosh around a bit.

Yeah – if it sloshes it’s fine.

Cheers

OK, boys, but would it still slosh around a bit if there was 140 gm. of n-butane inside? I fully understand that we have to be politically correct here, but what about the business of being fairly scientifically correct, as close as we can reasonably surmise?

Re-filling a canister with just 123 gm. of n-butane doesn’t really seem to be worth it guys. I love what you have done, Bob, especially considering our winter fuel efficiency collaboration late last fall. And I also like the fact that you rose to the task of addressing this before breakfast, Roger. But I still want to know what the maximum safe level of fill of n-butane would apply to this hypothetical situation. At least one inquiring mind would like to know…

Cheers, all. I am headed to bed now.