This report covers:
- The question
- Bulk-fill
- CO2 cartridges
- The deal
- Not the full answer
- The Komplete
- Summary
Today’s report is an answer to a question reader Decksniper asked recently. Let’s read what he said and I will take it from there.
“Do you or any reader who has tested it care to share their opinion on leaving an unspent CO2 cartridge (88 mm) in a Umarex Komplete air rifle?”
“It is well known that this rifle is actually dual purpose in being able to shoot with either nitrogen or CO2. Ham [Hard Air Magazine] review tests prove it and I use both in my Komplete .177 and .22 calibers. Accuracy is equivalent at reasonable ranges but velocity is far greater using nitrogen as expected. But CO2 delivers an incredible number of useful shots before a cylinder is exhausted. This lowers the cost of shooting to being very reasonable.”
“This gets back to my question. It isn’t practical for me, at least, to shoot 120 to 150 shots with any gun in one outing. I have too many airguns demanding their turn too. I’m hoping the greater hammer spring tension designed for nitrogen offsets the need to remove the CO2.”
The question
The question is—How long can you leave a CO2 gun charged? The answer is—it depends. In today’s report we’ll look at what it depends upon.
Bulk-fill
Sometime in the middle 1990s I bought a Crosman 111 CO2 pistol at a flea market. The lady I bought it from didn’t know how long it had been in the family. She said she found it in a drawer and I think she said it belonged to her late father. As far as she knew it hadn’t been touched in at least 20 years. It came to me in the original box and had the manual and the model 197 ten-ounce gas tank.
Crosman’s 111 bulk-fill CO2 pistol held gas for decades!
I took it home and went to my basement range where I immediately dry-fired it to see if there was any gas left. There was so I loaded .177-caliber pellets and shot about 30 shots before the power started dropping off. I refilled the gun from the tank that came with it. In all I fired several thousand shots before needing to get the 10-ounce tank refilled. The pistol got about 70 shots per fill, so it was about half-filled when I got it — after at least 20 years.
CO2 cartridges
Why then do companies warn us to not store our gas guns with CO2 cartridges installed? Let’s fast-forward to the 1960s. Crosman was making lookalike gas guns like the 38C and the 38T revolvers. The way those guns were made they often required a short pipe to conduct the gas from the piercing pin to the firing valve. That pipe had ends that were prone to leak.
This schematic of a 38C/T valve shows the pipe mentioned above. It’s part 38-065.
The deal
So, if there is a possibility of leakage when CO2 is stored in a gun it’s recommended to not store it with gas. The other reason is safety, because anything that’s in the barrel can be propelled by the gas. It’s kind of a loaded gun!
The bulk-fill guns have a seal at the gas port inlet and of course the firing valve is entirely sealed. There is really no good way for gas to escape. Of course all seals fail in time, but bulk-fill guns usually hold gas for a very long time, as you read above.
Most CO2 gas guns that use the smaller 12-gram (and 8-gram) cartridges have pipes like you see in the schematic. That’s true for most guns but not for all. You have to check and see if yours does. And they nearly all have face seals that are thin and prone to tear and leak.
But what about the guns that use those 88-gram and larger cartridges? That’s what Decksniper is asking about. Back in 2014 I wrote about a Crosman 1077 that was converted from using 12-gram cartridges to an 88-gram cartridge—the exact thing Decksniper wants to know about!
My 1077 has an adapter for an 88-gram CO2 cartridge that Crosman used to sell. The round knob at the bottom shuts off the gas flow so the cartridge can be removed from the gun with gas still inside the cartridge.
Not the full answer
That conversion is no longer made. So what about 88-gram CO2 cartridge guns today? Can their cartridges be stored with the guns? And even more to the point, what about those Nitrogen cartridges? Is it safe to store the gun with them? Here is what the Umarex Komplete manual says:
“If you choose to store your airgun with a nitrogen cartridge in it, always store your airgun in a secure (locked) location away from unauthorized users and separate from ammunition.”
Umarex addressed the specific question and says that it is okay to store the rifle with the gas cartridge installed, as long as all safety precautions are taken.
The Komplete
I have an Umarex Komplete to test for you and if this question had not been addressed I would have tested it. But I would also have told you beforehand that the rifles that use these large cartridges, both CO2 and now Nitrogen, are built more like bulk-fill CO2 guns than like 12-gram cartridges guns. I would have predicted that it was okay to store the rifle with the cartridge.
Summary
I hope you now understand what “it depends” means, as an answer to today’s question. With this knowledge you should be able to figure this out yourself for each new gas gun you encounter.
My recommendation if you are going to store a CO2 gun with a cartridge in it, make sure you put a few drops of Pellgun Oil on the tip of that particular cartridge. It will keep the seal pliable and stop the cartridge from sticking to the seal. Guess how I know that can happen?
Tom,
Knowing that the Komplete is capable of using both CO2 and Nitrogen would it be safe to say that only silicon oil should be applied and not Pellgun oil?
Siraniko
Siraniko,
Nitrogen does not support combustion, but air does and since the Komplete could be converted to accept high pressure air I’m going to say yes.
BB
Silicone oil is key to all cartridges. Just one or two small drops on the tip.
After about 5000 shots I had to replace the valve in my Crossman 2240. When the valve doesn’t hold – oil won’t help…
For me, stopping shooting means removing the rest of the CO2, if it hasn’t been completely used up, to clean the gun and let it “unloaded” for the next shooting session.
I understand the question about such a large cartridge. There will be no clear answer – you just have to leave it and check the result after some time. If it holds – great! If not – then you will probably do longer shooting sessions after this experiment 🙂
I believe the ability to leave a cylinder in the rifle is for Nitrogen; Umarex doesn’t really promote the use of CO2 in the Komplete. So it’s going to have to be trial and error to find out if CO2 can be stored without leaking.
OP,
The CO2 molecule is larger than Nitrogen atoms, so CO2 will be the last gas to leak and you are correct that Umarex doesn’t promote the use of any gas other than Nitrogen.
BB
B.B.,
Compounds, Elements, Molecules, and Atoms are often misunderstood.
You are mostly correct in that the Compound CO² (composed of the Carbon and Oxygen Elements) is much larger than the N² molecule.
Nitrogen N is an Element. Nitrogen gas is N² and is made of two Ns therefore a molecule. Molecules can be made up of same Element multiple Atoms or Atoms of Different Elements of various numbers of Atoms in combination.
shootski
PS: and then there are the Mixes that are even worse…like air,
shootski,
Thank you. I learned something.
BB
B.B.,
We grow old slower when we keep learning every day;
a blessing from God.
You are very welcome!
shootski
OP,
The carbon dioxide molecule is larger than the nitrogen molecule.
RidgeRunner,
You got this!
shootski
Having a large amount of gas left after a shooting session is likely one of the reasons for not having one of these around. I can see where the expense of the gas cartridges would also be prohibitive.
There is/was an aftermarket valve system for these cartridges that allows them to be removed and retain their contents. One would think that Umarex would have such a product, though I can envision someone using such to recharge the cartridge at too great a pressure and creating a bomb instead.
RR
Umarex indeed have a “cut off” co2 system and promote it with their new T4E M4 clone. Very interesting airgun by the way.
BB
Thank you for thoroughly explaining your answer. I will continue to use my two Kompletes as dual purpose for either nitrogen or CO2. If I have any problems I will let you know. By the way, the Umarex Komplete is the cat’s meow.
The cost per shot for me is reasonable especially when it’s CO2 season (usually 8 months a year). One of the blessings of having way too many airguns demanding shooting time is none gets that many shots.
Deck
Deck,
Believe me—I know the blessing of having too many airguns! 45Bravo, care to comment?
BB
I would! Last night, I started the process of my annual gun spring cleaning. Starting with a Winchester 416 (Diana 16), then moving on to a couple of Win. 422’s. I also wiped down the Walther Terrus .22 upon which I had installed an old Beeman scope for testing a while back. I paused my cleaning duties to feed it some Benjamin “Bullseyes,” which I had never tried in it before. It turned in a very respectable .21″ (5.334 mm) group at 10 yards. As good as it’s previously favorite pellet, the JSB Straton from the JSB .22 multi-pack. I also tried fiddling with the trigger adjustment screw, but turning it counter-clockwise just extended the second stage travel, so I cranked it back as far as it would go. I didn’t eliminate the second stage travel, but I shortened it to about 1/8″ (3.175 mm). The good thing about the Terrus is that it LIKES the “deer hunter hold” (firmly into the shoulder pocket and left hand gripping the forestock firmly near the stock screws), so it is good off season practice for my deer rifle. Also good was no barrel seasoning needed. All 10 shots went into a pretty, little (and pretty little) cloverleaf group.
Ah but I digress, I also wiped down a couple of Winchester 425’s (Diana 25), one of which has a peep sight installed. I took the opportunity to adjust that trigger too, using B.B.’s Diana 27 instructions, and improved the release by quite a bit. Out came the Benjamin “Bullseyes” again and although they made a one hole group, that group was about 3/4″ (19mm). This gun is a beauty, though, in that it makes similar groups with a variety of pellets. The best groups came from HN Excite Plinking pellets if you can believe it.
Many more guns to go….
Yes you do know the “blessing” more than any one I know.
Actually if I took 10 of my Airgun friends and combined their collections, it would still pale in comparison to yours.
Let me say to the readers that they are stacked up against every wall like cord wood.
I walk through there and it is like a wish list, from mass produced Airguns, to SHOT-SHOW “announcements” that didn’t catch on, to ones you ask “what the heck is that?”
It is an airgunner’s candy store.
And I haven’t peeked in the closets at your house yet…
I am trying to catch up with you though.
When we moved last year ,my firearms were moved wrapped in blankets or soft cases crammed tight into 2 gunsafes.
Just my air rifles in hard cases or factory boxes took up the entire rear of my wife’s Toyota Sienna mini van from floor to ceiling, with the seats folded flat..
I say I need to downsize, but I just can not seem to do it…
I am not complaining.
And I will throw this out there for public comment.
We have upgraded to a larger mode of transportation . (Hint hint!)
Ian.
45Bravo,
I think all those guns are substitutes for his fur babies.
Downsizings are tough regardless of what we have accumulated for most of us.
I’m finally getting rid of all my computer and electronics that i have been trying to keep running since the late ’70s.
shootski
Deck, the Komplete was interesting when it came out, but I did not see it as a replacement for a PCP (like the 3622 or other price point PCPs) over the long haul due to the initial price of the Nitrogen bottles. But since you are clearly a fan, tell us more!
1) What is your average price per shot with Nitrogen vs. CO²?
2) Do you use the same pellet with both Nitrogen vs. CO²? How does the gun shoot with each?
3) Do you use Nitrogen for different purposes than CO²?
Roamin
These CO2 cartridges cost less than Nitrogen. The cost per shot depends on where you buy the gas as well as the number of shots you get. If you buy enough airguns and shoot them all equally in rotation like me, the cost per year (for me) is around $75 total for both nitrogen and CO2. Conversely if you intend to shoot the Komplete often, the cost is much more. Using nitrogen the .22 Komplete should be a fine choice for hunters. I stopped hunting years ago so I’ll be using more CO2 than nitrogen.
I do use the same pellets for both gases in .22 caliber (JSB 15.89 gr Hades) and too early to know for my .177 Komplete. So far my .177 seems to be as accurate as the .22 at 20 yards.
Using Hades pellets I’m getting between 2 and 3 MOA at 33 yards shooting 10 shot groups with nitrogen. At 20 yards I’m getting just under 1/2” ten shot groups with both nitrogen and CO2.
Deck
Thanks.
Roamin
Update on .177 Komplete. I’m getting same accuracy with .177 and JSB 10.34 gr using CO2 at 20 yards as the .22 above. But when I switched to nitrogen the JSB’s landed in two clusters. While the group measures 3/4 inch this is not as good as CO2 delivers. I will test other pellets.
I got 96 good shots on the CO2 cartridge in the .177 Komplete, less than I expected but not bad.
Deck
Cool. This is turning into a mini guest blog!
Decksniper
There are a couple of Umarex products you might be able to use with your Komplete rifles that would possibly alleviate your CO2 concerns.
Umarex still has the 2 x 12g CO2 adapters that work in place of the 88 g CO2 cylinders. If you want to use this adapter, you have the option to use it with 2 full 12 g cylinders or 1 full and 1 empty 12 g to control how much CO2 you use in a shooting session.
https://www.pyramydair.com/product/umarex-12g-co2-adapter-set?a=9620
Umarex also has its own 88 g CO2 gas saver adapter that screws onto the top of the 88 g CO2 adapter. With the gas saver adapter installed, you can use as much or as little of the 88 g of CO2, and then remove the adapter / cylinder from the rifle. The check valve in the adapter immediately closes to prevent loss of CO2.
https://www.pyramydair.com/product/umarex-88-gram-co2-saver-adapter-fits-airjavelin-fusion-2?a=9888
I’ve used both of these on a few of my CO2 powered rifles. They work very well.
cstoehr
Did you find the threads on 88 g Gas Saver adaptor to be too coarse to prevent leakage?
Deck
Decksniper
I’m not sure what you mean by “too coarse to prevent leakage”. As far as I could tell, I had no problem with the threads on the 88 g Gas Saver adapter and no leaks either.
The one important thing to know about using the 88 g adapter is screwing it on “hand tight” is not enough. For successful use, it is imperative to clamp the 88 g CO2 in a vise and use a crescent wrench or hex wrench to tighten the adapter onto the 88 g CO2.
The adapter will seal on the 88 g CO2 with a “hand tight” fit, but when you attempt to remove the adapter and partially filled cylinder from the rifle, the likely result is that the cylinder will loosen and screw out of the adapter before the adapter stem loosens and screws out of the rifle thus releasing the remainder of the CO2 in the cylinder.
I made that mistake of using a “hand tight” fit the first time I used the adapter on an 88 g cylinder and installed it in my Hammerli 850 Air Magnum rifle. Everything worked fine and was leak free, but when I tried to screw the cylinder with adapter out of the rifle, the cylinder came loose from the adapter and I lost half or more of the CO2.
I hope this answers your question. Otherwise, post another comment, and I’ll reply in the morning.
cstoehr
Very helpful. Thanks!
Deck
No such thing as too many airguns, decksniper!
OhioPlinker
Yeah, I also have a convenient shooting setup. A majority of my airguns are stashed in our bedroom closets, nooks and crannies. Even cleaning stuff and small compressors are in our master bedroom. The Ms lets me get away with it because she knows I love it. I can be shooting from bedroom deck within 5 minutes.
Deck
CO2 is a strange molecule it is like water that in its liquid state will dissolve most other fluids ie oils. It will also slowly diffuse into any polymer, the o-rings and seals in the system. Then if the system is rapidly depressurized the seal / o-ring can under go an explosive decompression as the CO2 gas inside the seal will rapidly come out and tear the seal apart. Other gases also do this also but not to the extent of CO2, particularly when in the supercritical state, temperature above 88 F. There is also a time component, the longer the time the more CO2 diffuses into the seals. In addition the rate of diffusion is also a function of the polymer of the seal, some materials the CO2 diffuses relatively rapidly and are more prone to explosive decompression.
Leaving the cartridge in place should not be a problem if the CO2 cartridge is slowly depressurized by shooting versus a half spent cartridge just being spun open and replaced with a fresh cartridge.
So my best advice is to use the CO2 up before removing the CO2 cartridge, and store the air gun safely if the cartridge is not removed.
Mike
I leave all of my CO2 guns charged without any problems.Some are face-seal, like my Plinkster, Chaser, Crosman 782, and Webley Mk VI. A couple use a pressurized tube, like my Alfa Proj and Tau 200. One, my Daisy 887 uses a proprietary refillable 2.5 oz gas cylinder. The only CO2 gun I have that does leak down over time is my QB, which I have modified to use the Daisy cylinders or a RAP4 dual-cart cylinder. It has a very slow leak in the gas block, and I’ll rebuild it soon to fix it. All the other guns hold gas for months at a time. I use a single drop of ATF on each cart when I put a new one in.
The piercing caps on the Tau and Alfa had Buna N o-rings, which would absorb CO2, and would need to rest before recharging. I replaced the o-rings with urethane, and that problem was solved. I was taught that any seal in direct contact with CO2 should be urethane.
Jiminpgh & BB
So you use ATF rather than Pellgun on CO2 cartridge tips. I was enabled by BB to use ATF to stop leaky CO2 airguns and have it on hand. But I wonder if enough ATF gets blown out to overcome any unwanted buildup over time?
Deck
Someone one told me that Pellgun oil is really ATF fluid. That’s why it’s red. The stuff B.B. recommends is ATF with an additive for stopping leaks, if my memory serves me.
Roamin,
According to Dennis Quackenbush Pellgunoil is 20-weight non-detergent motor oil with an o-ring preservative that gives it the red color. I once asked a Crosman engineer about that and he wouldn’t tell me that it was, but he did say, “I wouldn’t tell you that it wasn’t, either.”
BB
…and 11 herbs and spices…
Have left partially-charged CO2 cylinders in the Umarex MP40 for months without experiencing any leakages. When installing the cylinders/cartridges made sure to oil the cartridge tips with the red Pellgun oil. The “house” 38T has been another story. Seem to recall when first shooting it in the ’60s-’70s there were no leaks and many times the gun was left with a partially-charged cylinder in the holder. Ironically, neither the cousin who was the original owner nor FM ever thought of oiling the cartridge tips back then.
After a rebuild about 4-5 years ago, the gun shot fine for a while, no leaks, pretty much sticking to leaving cylinders inside. Then, even before the revolver had been fired over 60-70 times in a year’s time, upon loading a fresh cylinder one fine day, it leaked down completely. This was traced to the ring around the port into which the cylinder neck fits coming loose. FM tightened it as best he could but not sure the leak gremlin has been fully defeated. Gotta get that Round Tooit and test the gun.
Just wonder if better-quality materials were used, particularly seals, when the gun was assembled at Crosman around 1965. Maybe that explains why this particular 38T went years without leaking though CO2 cartridges were left inside it all the time.
And I always thought the reason for removing the CO2 cartridge was to avoid distorting or crushing the seal.
As far as storing a loaded airgun, all guns are to be considered and handled as being loaded, all the time. Unless of course you are a movie star, shooting a blank into your head or making a western and playing games with it and killing a costar.
Is anybody out there receiving internet home page stories about things discussed on this blog?
Two topics I recently discussed with Shootski were immediately followed up with front page news stories on my MSN internet home page:
1) “What is rev matching” (Manual auto transmission)
2) “Is it okay to skip gears in a manual transmission?”
And I can’t count the number of airgun topics they send me. internet surveillance is unbelievable here.
In hind sight, I did search for info on both. May just be coincidence.
Bob M,
The World is changing to who knows where…
We have signs being posted around the DMV that say, OBEY THE ZUCC, ∞ Beta with a picture of Zuckerberg with his tongue stuck out…
shootski
PS: Granny Shifting is both up or down without skipping gears that’s what i was taught. So going from 2nd to 4th is not Granny Shifting; just as downshifting from 5th to 1st gear is WAY NOT granny shifting. Be certain to rev match on that one!!!
Let’s see if that hits your Homepage ;^)
Shootski,
I received three more transmission stories. One compares the cost to repair each, auto and manual and another on how to take off from standing still. I think they have exhausted the subject now.
Airgun emails are another story. Gamo has a PT-80 Desert Attack CO2 Pellet Pistol and CFX-22 underlever rifle on sale, and Daisy Outdoors has some Combination Kits and stuff discounted as well.
Then AOA has another tactical PCP the RTI Mora costing over $2500.
Pyramyd Air has cut back the mail, but I will always go to them first.
This summer is predicted to be hell all over the country, storms, fire and excessive heat. Need to get a jump on it. No time for airgun play.
Wow, although I’m “late to the party,” I found so much great info here, and so many informative comments, that it made me feel stupid just reading it all, LOL! =)~
Seriously though, that’s what I love about this blog; it makes for such a great learning experience. 😉
Thank you to BB and all commenters,
Blessings to you,
dave