Guys (and gals?), I just got a .22LR barrel from Spike's this afternoon. The barrel started it's life, presumably, as an M4-profiled barrel before it was cut down to an OAL of 9.75", re-threaded, re-crowned, and re-profiled "as small as possible, skinny as possible." The barrel looks pretty nice; however, the diameter under the handguard is ~0.690" which doesn't seem like much of an improvement over an M4-profiled bbl under the handguard. (Admittedly, the only other bbl I own, against which I can compare Spike's work, is on an LWRC 10.5" M6A2.) I'd give Spike's a call and ask them if ~0.690" is really the best they can do, but it's pretty late in FL right now; so, I was wondering if anyone with a Spike's lightweight dedicated .22LR upper receiver could tell me the diameter of their bbl under the handguard.