Terry,
You do NOT want to put more psi in your Marauder anyway, so there is no problem...........unless the gauge on the gun is wrong, and you ARE putting 3500 psi in it, which you should NOT do!!!!! I would always go with the gauge on the tank you are filling from for the more accurate of the 2. Marauder gauges are not known for their accuracy. If you have a Marauder of any caliber, and it is regulated, overfilling it over 3000 psi could damage the regulator. If it is not regulated, and you fill to over 3000 psi, you'll get valve lock, and you may not be able to degass the gun with the degassing tool. Now you'll have a bigger, more dangerous problem to deal with. Do not fill over 3000, and don't go by the gauge on the gun.
Tom Holland
Field Target Tech
Fieldtargettech.com