Benjamin maximus dual fuel?

Jump to latest Follow Reply
Gabpan

Gabpan

Member
Mar 29, 2020
123
1
MI, United States
As I understand the disco was duel fuel. The Benjamin maximus I am not sure of. I heard it used to ship with a gauge that showed both. Mine does not have the co2 combo gauge.

So... Pretty sure I could use co2 but no idea what the max fill is. Maybe I could order a disco gauge from crossman.

Also what attachment adapter would I need going from a 5 lb tank to the fill port? Thinking I could keep a tank in the basement range and run hand pump when at the range.
 
When these first came out, I asked the same question. Net effect of the answers is that Co2 is a huge molecule compared to nitrogen (%78+/-) of atmosphere.

The valve needs to be designed differently for Co2 guns. It runs at about 800psi while the maximus runs 2000, iirc. The Co2 bottle for our keg cooler is stamped 1200psi max fill pressure.

Good luck with the project, all the same.
 
Upvote 0
Found this so I may not need a gauge. I'll just fill to what would be 1000 psi on air. 1000 psi point is max co2. 

PY-A-7350_Gauge-for-Crosman-Challenger_1458664071.1622345194.jpg


Just need to find the proper fittings. Tuesday I am going to airgas to see what they have in the way of co2 tanks. I'll take the rifle with me to figure out fittings.

Currently have the thing filled with air to 2k psi. I am going to let it sit for 3 days and monitor the gauge. It can from crossman with a completely empty tank. 


 
Upvote 0
The Maximus could take the pressure of Co2 as it is lower than the 2000psi fill pressure of the gun. For a gun to run decent on Co2 it needs bigger ports through the valve, T-port and the barrel to do so than that of a PCP gun. Without the larger ports your power on Co2 will be limited and with the lower pressure of Co2 even more so. 

The only other problem would be the materials inside of the gun. Co2 is not as as kind to some materials as air so their lifetime can be shortened. Some manufacturers state that their guns should not be used with Co2.
 
Upvote 0
The Maximus could take the pressure of Co2 as it is lower than the 2000psi fill pressure of the gun. For a gun to run decent on Co2 it needs bigger ports through the valve, T-port and the barrel to do so than that of a PCP gun. Without the larger ports your power on Co2 will be limited and with the lower pressure of Co2 even more so. 

The only other problem would be the materials inside of the gun. Co2 is not as as kind to some materials as air so their lifetime can be shortened. Some manufacturers state that their guns should not be used with Co2.
Click to expand...

One of the thoughts that ran into my mind was the liquid co2 in the tank and cycling between air and co2. I wonder if it would accelerate the possibility of rust in the tank. 

I know it's not the same but at work we have a large air compressor that constantly needs to be drained from the bottom because of the air it sucks in. Not sure if liquid co2 will react favorable to that.

I am new to PCP and honestly don't know much about pneumatics period. I think you are spot in about the larger valve. I read something about the molecular structure of co2 being Larger several times. 

It blows my mind that the size of molecules comes into play. No pun intended.
 
Upvote 0
You must log in or register to reply here.
Top Bottom
Back
Home
Forums
Resources
Menu