From the Discord:
There is a sequence on how you should adjust the outer barrel, but there's several approaches to this.
Prep:
Before you go about adjusting the outer barrel for the handguard or hopup unit, adjust the outer barrel such that the dust cover will seat correctly. The positions of which your dust cover would seat into the rear trunnion is the range of positions that you could set your outer barrel at.
For the AKS-74U/MSU, the dust cover is secured using a set screw at the bottom of the dust cover hinge. You want to adjust the outer barrel as per the below process and then secure the dust cover hinge last.
But in a nutshell, any of these faults is a failure criteria:
* Dust cover is too tight
* Hopup dial is jammed / pinched bucking
* Handguard retainer won't lock / lock-pin does not reach the groove
Process:
If you are trying to fit a handguard that requires several extra turns such that the retainer tensions correctly, get as many turns in without jamming your hopup.
Scenario a) If the handguard is tight but your hop is running loose
shim the hop unit itself
Scenario b) Hopup is jammed but handguard is still running loose
shim the handguard
(edited)
[8:47 AM]
Reserved (edited)
comradebear — 01/03/2023 9:05 AM
Note: Shimming the hopup is highly dependent on which hopup unit you're using that isnt TDC. Nominally I have to add o-rings to the BM and Maple units but have to remove the provided o-ring on the TNT unit as it is usually redundant
Additional note: This has to be done from scratch if you're swapping outer barrels / upgrading to steel outer barrels
Installing the Maple leaf hop unit
1.1) NEVER file the alignment winglets. If your unit's alignment wings appear to be slightly offset towards the bottom of the unit, this is normal. The two winglets are not coaxial to the bore.
The way to know if you have lost the GHK lottery is if you have to take a mallet to the unit to go in and the top of the unit is getting sheared off (See attached image). Otherwise, it's probably just your c-clip not seated correctly
But seriously, it's most likely the c-clip because you can check by seating the hop unit in place without installing the inner barrel
1.2) The ML unit is very sharp so if it's shaving material off your nylon feed ramp, you probably have a minor misalignment. As long as you can install the feed ramp without forcing it in however, it should still feed.
2) NEVER file the c-clip. If you have issues getting the clip to seat flush, you've probably deformed it by failing to seat it into the groove correctly in your previous attempts. Crimp/bend the c-clip inwards and try again
3) The ML dial is more prone to getting jammed than the other hop units by design due to the way it interfaces with the trunnion. If you're getting a jammed dial but an otherwise perfectly good alignment you may want to consider the TDC mod to circumvent this issue
4) If your BBs are rolling out you probably haven't applied sufficient hop. You need at least on average 30% dial to get any grip on just 0.2g, higher for heavier weights and bucking hardness
