I don't want to say something that might cause someone to get hurt , as I always beloved safety first. But here it goes. I have an app called Chat GPT.
This AI app is very smart it can do formulas in seconds that would take me lot's of time. This what it said.
The internal regulator can be turned up to 3,000 psi. The Zelos operating pressure is 3625 psi , and has a 5,000 psi burst disc. So if you put on a bottle adapter, and filled the bottle to 4000 psi which is 375 psi over the normal operating pressure. It should be fine.
I never tested this theroy. I only fill the new 500 cc bottle to 3,625 as this is double the 250 cc tube. My regulator is set to 2,700 which propells a .22 caliber 28 grain hollow point slugs like a laser beam. I was able to shoot a target with 40 red sharpie dots at 40 feet , and hit every dot before the regulator fell below 2,700 , and that is fine for now untill I get my 700 cc CFB
From eBay for $138. Now being as I use my Zelos only for bench rest the 500 cc aluminum bottle works fine for me at 2.2 pounds. The 500 cc round bottom aluminum bottle sells for 39.99 on Amazon. The Carbon Fiber Bottle , or CFB cost about $100 more , but if you are hunting it's lighter , and every ounce counts when walking several miles. Now the Huben Regulator is worth every penny as you can fill that 700 cc bottle to the full 4,500 psi , and the regulator to same as what it is set on the Zelos and have a safe rifle with a lot of shots. I don't have a Chronograph yet , but when I get one it will be awesome to tune my pellets to that sweet speed. Good luck , and remember SAFETY FIRST. It's not worth damage to an expensive gun, or your face. Happy Shooting , and God bless.