Originally Posted by
KevinF
This. I have some generic C02 inflator that fully encloses the cartridge. Works with either threaded or non-threaded cartridges. As said above, the unthreaded ones can be bought cheap at WalMart. I think I bought the same 25-pack years ago and I probably still have about 10 of them left. (I've probably used more in checking to see if the damn thing still works then I've used roadside). A 12-gram cartridge will get you plenty enough pressure to get home; 90psi if I remember correctly.
How much the cart fills varies with what size tire you run and the rim size.
I've switched to running 28mm Sector tubeless on Belgium+ rims (25mm brake-to-brake, and 20mm internal)...which IRL results in a 32mm tire when inflated and measured with a caliper. a lone 12g cart is only half a fill or so from zero. Another nice trick with the small carts and enclosed CO2 guns is to keep a dime with you. When you mean to inflate, put the dime in the bottom of the cart holder before twisting the cart holder (and cart) into the inflator head. Makes a nicer seal and you loose less gas.