M4 takes two trigger pulls for one bb? Barrel/Hop issue?

[RabidNinja64]

So, decided to cut down the barrel of my M4 awhile back for a more CQB style setup, so installed a new maple leaf inner 6.02 barrel, along with a new ML hop rubber into my stock hop unit. It worked fine initially but am now having issues regarding a consistent feed. One trigger pull shoots nothing, a quick double tap shoots one and begins feeding, until after waiting a few seconds i have to double tap again. Ive also noticed that adjusting the hop does no significant change to the hop rubber, let alone turning it off or all the way on. Ive tried with multiple magazines also.

Would it be worth replacing the unit too? Or should i just check the barrel/rubber to see if its a clearance issue?

Edit: the gun in question is the PJ CASV (A&K clone brand)

 

[Rogerborg]

Maple Leaf hop rubbers have longish lips that can cause feeding problems.  You might want to sand them down a little.

On the hop adjustment, are you running the stock nub, or a Maple Leaf omega, or something else?  I've found that with a Maple Leaf rubber and omega nub that I'm overhopped on 0.2g even with the hop right off, and that's on two hop units.  I had to put the stock nubs back in.  But a third one with that combo is just fine. We're talking fractions of a mm here, you may need to go with a bigger or smaller nub to get yourself into the right range of pressure.

 

[RabidNinja64]

The parts in question:

https://www.taiwangun.com/en/precision-inner-barrels/290mm-6-02-inner-barrel-for-aeg-maple-leaf?from=listing&campaign-id=14&q=290mm

https://www.taiwangun.com/en/hop-up-rubbers/hop-up-rubber-70-monster-maple-leaf?from=listing&campaign-id=14&q=Maple+leaf+rubber

With the rubber, i bought the 60 degree, NOT the 70, due to my fps being between 300-350. Unsure if the monster rubbers are any good?

 

[Adolf Hamster]

Maple Leaf hop rubbers have longish lips that can cause feeding problems.  You might want to sand them down a little.

[/thread]

On the hop adjustment, are you running the stock nub, or a Maple Leaf omega, or something else?  I've found that with a Maple Leaf rubber and omega nub that I'm overhopped on 0.2g even with the hop right off, and that's on two hop units.  I had to put the stock nubs back in.  But a third one with that combo is just fine. We're talking fractions of a mm here, you may need to go with a bigger or smaller nub to get yourself into the right range of pressure.

that's gods way of telling you to use heavier ammo

 

[Rogerborg]

hat's gods way of telling you to use heavier ammo

God has been over-ruled by the site owner who limits it to 0.25g.  And indoors at CQB ranges, it's not even worth paying for that.

 

[Adolf Hamster]

God has been over-ruled by the site owner who limits it to 0.25g.  And indoors at CQB ranges, it's not even worth paying for that.

see i can accept the cqb argument, although not sure i like sites limiting ammo weight arbitrarily, sure it carries energy at range but it'll never have more than when it started.