Are all hop up units like this?

[lazareth1]

Hi Guys,

 

I've come across 2 piece and 1 piece hop up units but both are the same in that the aperture that the hop up nub protrudes from is slightly off centre so when the bump comes down into the barrel to give the spin on BB you can see that the bump isn't symmetrical. Are all hop up units like this? Seems silly to have this sort of thing off centre, especially as this would have an adverse affect on the accuracy!

[RR01]

It sounds like you need to try turning the inner barrel very slightly in the hop unit. There is a small amount of movement in them so that you can get the alignment perfect.

[lazareth1]

It sounds like you need to try turning the inner barrel very slightly in the hop unit. There is a small amount of movement in them so that you can get the alignment perfect.

Yeah that's exactly what I mean and I have to do that with most of my hop up units. Seems strange because when you do this, the C-clip groves then no longer line up. Bad design in general I think. Just confused as why the BBs don't fly off to the left or right is all!

[RR01]

It might just be your hop rubber is made slightly out of line. Try a different brand of hop rubber first as the cheapest solution.

 

As regards your first question, two piece hop units were mostly for TM M4s, where the upper receiver was hinged at the front and held in place by the rear pin, so that the receiver could open like a real M4. Most clones use a one piece hop as the receiver splits be being pulled forward, not upwards.

[lazareth1]

Thanks guys it's now fixed. It turns out the FPS was way down and after plugging up a leaky cylinder head and air nozzle it's now going out to ranges of 30 metres +. Brilliant.