in order to make a solid steel rifled barrel for a Null-22, how long has it to be it in total? all chamber+rifling+thread Should it be 100mm long? I can't fin it specified nor in the readmes nor in nthe not-a-glock instructions, I only found the guide rod size which should be 3mm od x 70mm lenght. the immortalrevolt's guide for .22lr barrel making says either 114 or 144mm but that's not related to these pistols. please help any explanations on Null-22 or NaG are welcome, I like those builds the most since almost everything can be printed or built with common parts, but there is a lack of clear specs and instructions.

Also, anybody has experience making a rifled .22 steel barrel? planning on boring a 12mm od 5.4mm id tube to 5.51mm bore then rifle it to 6.64 than chamber it and die the 1/2x28 thread. any advice? could be an option instead to just "sand paper roll bore" the inside from 5.5 to 5.51mm?

thanks to everyone who knows this topic and will take the time to answer!