Indeed, Rob and I encountered the length differences between the deac. Sterlings/MR Blaster and various fan made blasters - the MR/Sterling being a bit longer than some fan made ones - this being because of the end part of the blaster. The MR blaster has a steel rail, my Sterling has a bronze rail and have seen people using aluminum or plastic too. The best way would be to go to a hardware shop and get some metal after you measure up your own blaster, or at least ask someone to make it for your exact blaster dimensions.