Talk:Powerlet

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Just a little more info about Powerlets.

(1) CO2 cartridges are colloquially/generically referred to as "carts" or "12-grammers."

(2) I think "Powerlet" is actually a Crosman brand name. Daisy still sells their own CO2 cartridges, which used to be called something like "Jett-air" in the Sixties, including a smaller (8g?) version which was pretty useless. Other no-name off-brands are available in bulk by mailorder. I'm not sure if any manufacturer these days includes oil: Various airguns' factory valve lubricants could be incompatible, especially if silicone-based, and I have repressurized sodas in 2-liter bottles with 12-grammers to no ill effects.

Crosman's invention of Powerlets revolutionized the airgun industry by providing more rapid fire than barrel-cocking or pumping between each shot. In particular, Powerlets' steady gas supply spawned the marketing of semiautomatic air pistols and rifles, as opposed to single-shot. Of course, the mass-production of Powerlets to satisfy the demand of this new market profited Crosman greatly as well. Pre-charged, disposable Powerlets were much more convenient to buy and use than, for instance, bulky scuba tanks or the welding-gas cylinders used by early paintball markers, since most airgunners at the time had no place to refill them.

[No, I don't work for Crosman, I just appreciate the genius of packaging airgun propellant in a compact, (super)liquid form which can be sold off the shelf instead of tiring the arm; plus semiautomatic airguns are a lot of fun.]

(3) In my experience, the CO2 inside an unopened cart is not exactly liquid, but in a supercritical or "superliquid" state, that is, sharing properties indistinguishable between liquid and gas. CO2 is supercritical above 1070 psi and about 85 degrees Fahrenheit. That's not much above room temperature, achievable in a warm fist; and according to my calculations, 12g of CO2 gas confined in a Powerlet's volume of 1 cubic inch would cause over 5000 psi! The most immediate evidence for superliquid is that carts balance easily, unlike refillable CO2 cylinders used for paintball markers, in which the liquid sloshing back and forth inside is obvious to the hand and ear.

When a powerlet is inserted into the airgun and "cracked" open, the temperature drop due to expansion into the volume of the valve and feed line permits CO2 to differente into discrete liquid at the bottom of the powerlet with vapor above it. As shots are fired more gas must "boil off" the liquid, thus cooling the powerlet well below room temperature. In fact the phase transition can suck so much heat from the surroundings that frost condenses on the metal cartridge, making it dangerous to touch without losing skin. This "frosting" tends to occur under rapid fire, in cold environments, and when unloading or "uncracking" a partially-used cart, whose leftover CO2 immediately vaporizes.

(4) Frosting is a common complaint with rapid-fire airguns using 12-grammers, because CO2 vapor pressure drops with temperature. Thus performance decreases markedly after a dozen or so quick shots. It doesn't help that some airgun designs feed from the cart horizontally, so that liquid CO2 can easily siphon into the valve if the gun is tilted. Not only does this reduce the available number of shots, but the sudden expansion of liquid CO2 inside the barrel causes erratic performance and can even corrode the barrel from cooling condensation.

(5) Powerlets are relatively expensive when compared to refillable gas cylinders, which also rarely frost due to their size. Having at one point accumulated a 55-gallon drum full of expended Powerlets, I can attest that they are non-recyclable as well. For these reasons some airgun enthusiasts jerry-rig coilhose adapters to remote CO2 paintball tanks. I've also installed battery-powered resistive heaters in my airguns so that they can still use carts, ameliorating the carts' frosting drawback while retaining their compactness.

Semiautopellet 21:04, 29 July 2007 (UTC)


 * While this main writing piece was added a full 15 years ago, it appears that as of only February 2022 it has been proposed to merge this article with the page: Crosman. I believe it's worth noting that while Powerlet may not be the correct term for referring to CO2 cartridges in general, there doesn't seem to be a page about CO2 cartridges, and this article contains a lot of the content befitting of such a page, mainly because of the wide variety of uses and applications of these small power sources. Corqe (talk) 22:10, 2 December 2022 (UTC)