TargetTalk

Hi there,

I picked up a used Walther CG90 air rifle this morning, and tried to test fire to see it's accuracy. However, the co2 gas was pretty low in the gun. As nobody knows the exact amount of gas for charging the cylinder, I have to find it out and charge up the gun before continuing my testing. Since the words and the numbers engraved on the cylinder body are so confusing, I just don't want to take a chance to fill up some gas right away.

Does anybody out there has a manual or knows about it?
I'd appreciate your help.

Thank you and best regards,
Raymond

I do not know the details for the original cylinder, but Walther lists the replacement CG90/CGM cylinder (Item-No.: 2768518) as 150 cc which would give about 75g of CO2. One of the great things about CO2 is that provided there is any liquid left in the cylinder you will get full velocity: so a charge of 30 to 40g above empty will give you lots (50+) shots.

the German/English manual download is at http://www.carl-walther.de/files/pdf/CG90.pdf

Just don't worry about. You can get only so much liquid in it. You may blow a little "snow" out on the first few shots, but you'll be fine after that.

You do realize the cylinder must be chilled before filling...just put it in the frig for 20 minutes or so. If you don't do this you cannot overfill it.

Thanks for all of the above advices, I appreciate that.

Regards,
Raymond

Like stated above, you measure CO2 fill by weight.
The cylinder should have tara (empty weight, I've got a CG90; mine says 0.601 kilogram) and CO2 weight (Kohlendioxid 0.100 kg) stamped on it. When full, it should weigh the sum of these two. Just use a digital kitchen scale to check it out.

Put it in the freezer for 5 minutes before filling, don't overdo it: it's possible to exceed the recommended weight; you should have a few grams of "safety" so the pressure doesn't go over the top if you leave it in a hot place. And you don't want liquid CO2 in the gun.

HTH

HTH,

Thanks for your input.
Now I know what the word "Kohlendioxid" means and will do it with confidence.

Best regards,
Raymond

Can some one tell me the muzzle velocity of your Walther CG90 air rifle?
Mine is leaking from the breech cover, only getting 435 fps. I'm still looking for those o-rings.

Thanks,
Raymond