One piece barrel inspired by the 3 piece from Igniz. Shorter (224mm overall length) version, to fit with the M-lok handguard by Igniz(https://www.thingiverse.com/thing:3734540).

Thread needs 0.16 or smaller layer height. Print vertically with threaded part upward if you have 230mm or more Z height, and use supports only at the bottom part(only touching buildplate). Threads does not need support.
You can print it a slightly angled if it don't fit vertically(sorry <220mm z height users), but this way threads will need support, so surface might not be perfect.
Depending on your machines tolerances, you might need to tweak your splicer's horizontal expansion settings.

ONLY FOR AIRSOFT USE!! This is NOT a real gun part.