Had to do a tune on this gun when it started deiseling to often ,come to find out they way over lubed it,i could of regreased my deck and wheel bearings on my riding lawn mower,that's why it had nearly no twang,i cured that by degreasing and molyed top hat and spring guide and velocity tared the outer spring and now,no deiseling just a thump when shot and just a tad of spring vibration,did'nt want to use heavy tar due to velocity loss.Anyway it's an excelent shooter for sure now,did have cant on the spring ,slid the cant side in first.Want a new sping but jm is out of the e3650 spring at the moment.