Crosman Intermounts.

[jh45gun]

These have gotten bad reviews because these current mounts 459 tend to wiggle when on the gun. I was told that the older discontinued 457 mounts didn't do that. These are a cheap way to mount optics on your Crosman multi pump 1377 ect and CO2 (2240) ect with out buying and installing a steel breech. You have to shim the bottoms of the mounts. Do this and they are rock solid. First thing you do is take out the cheap Chinese screws that can strip in the head and replace with American made screws. The size is 3mm x 16mm. Then buy a roll of magnetic tape with adhesive on one side. Cut off a piece about 1/8th wide and trim one end to fit the bottom of the mount. Put tape on each side of the tube below the barrel where the mounts will go. Set mounts in place and tighten down. With the tape shims the mounts are rock solid and you should be able to mount any optic to them.

[jh45gun]

11 dollars for these and a 4 dollar roll of magnetic tape makes for a cheap way to mount optics if you don't want to pay for the more expensive 35 to 40 dollar plus steel breech and have to take your gun apart to install. I have two guns with steel breech on them, but they were custom shop guns. I find if you want the steel breech and other mods like the shoulder stock the custom shop is a cheaper way to go.

[mac1911]

The problem is the mounts are made for a certain size tube. theres a B272 mount also. Im forgetting but ones for smaller tubes ones for larger.
Air venturi makes on that fits the .5" tubes. I run that on my crosman 1400s