Ahoy folks! In preparation for building several vac-u-destroyers, I decided to run some tests to find out which regulator is best suited for the job. After searching far and wide, and talking with as many other captains as possible, I bought three different regulators to test. They are, from top to bottom: 1) Rock Lite regulator from Palmer Pursuit shop 2) Battler's Connection regulator, with a disposable cartridge adapter from Palmer Pursuit 3) an "ebay kegger" regulator, most commonly used in vac-u-gearings The test setup: Since my destroyer will be as stock as possible, I used one of Phil's Predator cannons with a MAV-3 poppet valve for firing. A MAT-2 air tank was included as an expansion volume, and two pressure gauges were installed, one upstream and one downstream of the firing valve. Each regulator was verified with an initial starting pressure of 150PSI. Each regulator was tested with at least two 16-gram cartridges, firing in single shots and 3- to 5-round bursts, with larger bursts when achievable. The regulators were mounted with a significant up angle, to replicate the sort of mounting I plan to use in my destroyer. I also weighed each CO2 cartridge both full and empty, and counted rounds to see if it would be possible to get two full magazines from a single cartridge. Short answer: no. But enough with that! On to the regulators! The first regulator I tested was the BC regulator with 16-gram adapter. This combination weighed in at 114 grams, or 4oz. Starting pressure was almost exactly 150PSI. When firing, I noticed that pressure would return to normal extremely quickly. There were minor variations in the output, with average pressure during use around 145PSI and as low as 140PSI when the cartridge got very cold. Overall performance was excellent, as expected of a high-flow regulator intended to power major capital ships. The only noteworthy drop in pressure was during rapid fire testing, when the cartridge got so cold that it couldn't boil off its liquid CO2 fast enough to keep up with demand. The second regulator I tested was the e-bay kegger regulator. This massive metal monstrosity weighed in at 138 grams, or 4.87 oz. It does have a small pressure guage included, but most of the mass is from an unnecessarily thick valve body. I'd heard from several sources that it struggles with rapid fire, so I was interested to test. The kegger regulator is nominally adjustable from 0-150PSI, but in practice I found that the adjustment knob was very non-linear. It took a lot of turning to go from 0 to 50PSI, but it took noticeably less to go from 50-100PSI. The last stretch, 100 to 150PSI, was crossed with just the barest of nudges, and it overshot to 170PSI. I then had to back off and try again a few times to get it steady at 155. Further reduction would be needed prior to battle, but good enough for a test. I immediately noticed a significant difference. While the BC regulator recovered almost instantly, the kegger regulator was much slower to recover after each shot. Pressure would quickly climb up to around 130PSI, but it would take a good 15 seconds or so to return the rest of the way. Firing in spurts would cause pressure to drop much lower, presumably as I used up more gas from the accumulator. Of greater concern was the pressure drift. Over time, the pressure setpoint went up. Highest observed pressure was in the upper 160's. It may have gone even higher but I didn't have the patience to find out. Overall, this regulator proved overweight and underwhelming, but that's about what I'd expect from a cheap ebay regulator. My final test was the Rock Lite regulator. It weighed in at 70 grams, or 2.47oz. It is also by far the smallest regulator, which is an important consideration for a tiny destroyer. It was also designed for paintball use, which provides a good high flow rate. The Rock Lite is adjustable from 0-250PSI. Unlike the kegger regulator, it has a very smooth, linear adjustment of pressure, so it was easy to dial in the desired pressure of 150PSI. Then I started the firing testing, and that's when things went bad. The good news is that the Rock Lite provides plenty of flow, just like the BC regulator. Unlike the BC regulator, though, the Rock Lite had a terrible time maintaining its set pressure. Pressure varied wildly from as low as 130 to as high as 170. After a while, I think it stopped regulating at all, because pressure went up to 180 and slowly rising. When I touched the frost-covered CO2 cartridge, pressure spiked up to above 200. I tried dialing down the set pressure with no result. Several further extremely cautious shots showed that the pressure output only rose with heat input to the cartridge, so I suspect the regulator froze and stopped regulating, while the cartridge was so cold that it couldn't keep up with demand. This is not an issue I've seen before from Palmer regulators, but this particular one does it a lot. I'm curious if anyone else has similar issues, or if I just got a lemon. Other lessons learned: The 16-gram cartridges I was using are not actually 16-gram cartridges. After weighing each cartridge before and after, I found that 2/3 or them contained only 14 grams of CO2. Only one contained 16 grams, and the last contained 17 grams. On average, with a good tweak on the cannon, I was getting between 60 and 70 shots. Good enough for one sortie plus a bit of tweaking, but that's about it. Other captains have reported similar performance from their 12-gram cartridges. If that is the case, I wonder how much CO2 those 12-gram cartridges actually contain, and whether it's worth it to use larger, more expensive cartridges that can actually supply two sorties worth of gas. Speaking of gas, one of the noteworthy limiting factors in even the BC regulator's performance was the ability of the small cartridge to keep up with demand. It takes a certain amount of thermal energy to boil liquid CO2 into usable gas, and that energy has to come from somewhere. There's a certain amount of heat stored in the metal of the cartridge, but once that gets used up, it's all down to heat transfer from the air to replenish. This effect was quite noticeable with the BC regulator. After a particularly aggressive burst, the cartridge may be so cold that it takes a minute or more to recover back to normal performance. During rapid-fire testing with the BC regulator, pressure output dropped to about 100PSI, and did not recover until I warmed the cartridge with my hands. BC's regulator may be good enough to supply dual high-flow sidemounts at 10+ rounds per second, but these small destroyer CO2 cartridges certainly cannot.