TKO22 SAYS:The Crosman 2260 air tube has recently been changed by Crosman.The new tubes are marked: "2260MB". These ARE NOT THE same as the old 2260 tubes. They are 0.049 wall and machine very differently than the old "2260" tubes (0.065 wall). The 2260MB tubes also have a hard step at the front threaded end that will make it very difficult to get it to seal with a Discovery fill adapter. The 2260 tubes are chamfered for a smooth squeeze on the adapter o-rings.I have hydro'd a couple of the newer 2260MB tubes, and they failed at ~4100-4600 psi. In each case, the fill adapter blew out the front.I have assembled about 50 PCP pistols and carbines over the course of 5-6 years, using the 2260 tubes and no failures reported. I wouldn't use a 2260MB tube except for a Co2 cartridge gun.
I just found this warning from TKO22.... I have no first hand knowledge of this, but PLEASE check this out if you are considering using HPA on a gun equipped with a 2260MB tube.... Even bulk filling with CO2 would be questionable, as the safety margin if the gun is left inside a hot car would be less than 3:1.... CO2 can reach 1900 psi at 120*F....QuoteTKO22 SAYS:The Crosman 2260 air tube has recently been changed by Crosman.The new tubes are marked: "2260MB". These ARE NOT THE same as the old 2260 tubes. They are 0.049 wall and machine very differently than the old "2260" tubes (0.065 wall). The 2260MB tubes also have a hard step at the front threaded end that will make it very difficult to get it to seal with a Discovery fill adapter. The 2260 tubes are chamfered for a smooth squeeze on the adapter o-rings.I have hydro'd a couple of the newer 2260MB tubes, and they failed at ~4100-4600 psi. In each case, the fill adapter blew out the front.I have assembled about 50 PCP pistols and carbines over the course of 5-6 years, using the 2260 tubes and no failures reported. I wouldn't use a 2260MB tube except for a Co2 cartridge gun.If this is in fact true, this thread should be made a sticky, IMO.... Stay Safe !!!!Bob
The 2260MB tubes also have a hard step at the front threaded end that will make it very difficult to get it to seal with a Discovery fill adapter. The 2260 tubes are chamfered for a smooth squeeze on the adapter o-rings.
Why would Crosman change all tooling over to designate a model "2260MB" they do not sell?
Quote Why would Crosman change all tooling over to designate a model "2260MB" they do not sell?If I understand correctly it eliminates one step in the Machining process which is boring the ID out for the minor diameter of the 13/16-28 screw thread on the front cap. So instead of having to bore that out to .049 wall thickness they start at .049.Can anyone confirm that these 2260MB tubes are laser etched or are they also stamped like the previous .065 run?