FGC9 MKII Extended Rifling Mandrel - Wire Based Progressive Twist (390-10) 16.5in 8.82mm ID Barrel

thingiverse

This is simply an extension of the original rifling mandrel given in the FGC9 MKII files. I have had good preliminary results with making my own barrel, however I have not had the chance to use it. I produced this in a way where the twist rate along the mandrel changes every 10mm to produce the progressive twist, with the last 30mm of wiring being at a 1 in 10 twist rate. At the ends of each piece there are two holes that are 30mm deep each meant specifically for 3D printing filament. This will strengthen the connection between parts and help align the groves. I found the best way to feed the wiring through the mandrel is to feed it though one end of the mandrel, remove the wire from the groves so that you can pull it through by hand, then feeding the end of the wire through the other end of the mandrel in the correct hole. This will give you a wire that is fed through both ends, but does not sit inside the groves. You can then carefully push the wire into the groves using a flathead screwdriver. Make sure the wire sits evenly deep in the groves throughout the mandrel otherwise you run the risk of uneven rifling thickness in your barrel. (I'm currently seeing something like this in my barrel, but it doesn't seem to be affecting anything so far. This was due to an improper junction between two pieces that didn't match entirely (version 1 before 3D printer calibration vs version 2 after 3D printer calibration)). Print settings using HATCHBOX PLA Nozzle size: 0.40mm Layer height: 0.1mm Infill density: 100% Nozzle temperature: 230°C +-5°C Bed temperature: 60°C Cooling: None Build Plate Adhesion Type: Raft (I find this gives a little more stability) Disclaimer: As you all know, producing the FGC9 carries with it inherent risk. I do not claim any responsibility for injuries that may result from using these models in a way that may cause injury. If you choose to use this product you are responsible for yourself. If you like this file please consider donating: https://www.paypal.com/paypalme/WyldTurkey THIS PRODUCT HAS BEEN TESTED: https://odysee.com/@Turkey:d/FGC9_MKII_Extended_Mandrel:b https://www.youtube.com/watch?v=Sm3yt3ZCcRk