WE MSK/ACR Installation Guide
Everything you need from the WE stock gun.
Everything included in Daytona Gun Kit.
First, assemble the trigger assembly. Trigger, sear, reset spring (just one), and brass tube.
Drop the trigger into the trigger box. Remove the valve lever for more room if necessary, then reinstall.
Remove the two rear screws and steel arms, and drop in two tension pins and springs from rear. Then put arms and screw back in. Do not tighten the screws yet.
Drop trigger box into the lower receiver. Make sure the fire selector hole is aligned properly.
Put the fire selector in and fasten the top screws on trigger box.
(For how to cut fire selectors to make semi-fire functional, please check the fire selector guide).
Stack on the air valve and aluminum spacer. You can adjust the trigger mod in this step.
Replace the recoil spring with a Daytona Gun stiffer spring.
You can punch out the pin on the spring guide to take it apart.
Then you can push the spring guide into the bolt carrier, rotate, and lock it.
Grab the small aluminum bolt spacer and put it into the top end of the upper receiver, above the shell ejection port.
Cut off the plastic tube on the stock and enlarge the hole so that the airshaft will not hit it and cause damage/improper cycling.
Put the stock back on the lower receiver. Make sure everything lines up properly.
Assemble your hopup unit. Double-check your alignment to be sure the nub is centred.
Only use steel or brass barrels. Aluminum barrels will be bent.
Line up the undercut properly so the steel C-clip will not crush your barrel and mess up the alignment.
Thread lock every screw you touch.
Use a rubber mallet to hammer your hopup assembly into the outer barrel. Make sure the hopup adjustment screw is exactly lined up on top of the outer barrel. Sometimes you may need to sand the outer edge of the hopup unit to fit in.
Remove the bottom screw and feeding tube on your main hopup unit.
Align your main hopup unit and gently push it into the receiver. There are two side notchs on it, make sure they are lined up with undercut on your MSK receiver.
Then use outer barrel hopup assembly to push the main unit into the receiver slowly. Use a rubber mallet if necessary. Take care not to go over as you may break the notch on the hopup chamber.
Once you see the bottom screw hole exposed, you are good to go. Put the screw back on with Loctite. Then thread feeding tube back on.
Lock your QD outer barrel assembly then your upper is basically completed.
Lube your bolt carrier and put it back into the receiver.
Rack it a few times to be sure the system is aligned properly.
Put the receivers back together as well as the handguard.
Thread lock your front & rear iron sight and front handguard screws.
Your system is now ready to go.