First A&K PTW Issue
 

so i was ziptie'n my cheapo flashlight to my rail cuz i'm cool like that and went to fire the rifle with the light on cuz i'm cool like that and it makes a loud screeching noise. no screech when cylinder removed (m110 spring NOT the factory m150)
A&K PTW 1st Issue - YouTube

Sounds like your piston might be toast.
take apart the cylinder and take a picture.

teeth dont look bad at all, could one of the gears have wiggled loose and become misaligned?

https://fbcdn-sphotos-c-a.akamaihd.n...87479114_n.jpg

no idea what it could be, first "ptw"

Have you opened it entirely and inspected all moving parts?

Sounds like either piston (that you checked) or the sector gear (or whatever the pts temanology is for that)

On a side note i heard and seen there are full metal pistons for those. They are aluminum and they are swiss cheesed prety good to save weight.

I think your sector gear is not engaging the first tooth of the piston gear rack. If you have another cylinder, try that. Check to see if there is any wear on the first tooth of the piston. If the receiver fit isn't proper and the gear slips past the first tooth it VERY quickly wears it down (probably within one or two cycles) and will never engage again. I had a similar issue even on a PTW. Had to replace gear racks twice.

same sound with second cylinder. no noticeable wear on first or second tooth. is it possible the gear is getting locked against the piston and the noise is coming from the opposite direction?

If you can, check the pinion and bevel gears but this requires you know how to disassemble (and consequently) reassemble the lower. From your video it seems to cycle under no load fine so it's most likely something not engaging right when there's a load.

ya not sure how to do all that, i'll have to take it to my gun doc i suppose

I have one fly through my workbench (yes I am retired), The issue was that the sector gear was turning THE WRONG WAY!

Check your pinion gear! Last time i heard that, my pinion gear was loose on the motor.

Motor installed reverse polarity.

Or it is a lefthanded motor intead of a righthanded one. :D

You are the wind beneath my wings.