Rampage - darts get sucked into plunger

I just recently removed the AR from my Rampage and installed a spring (5+ kg by the description) from OMW and am loving the performance but I have a major problem.

It seems to jam almost every 5 darts or so and when I take a look a dart is stuck INSIDE the plunger, sometimes it actually fires out 2 darts.

I am aware that the Rampage it known for its jamming but I wouldn't have though an extra spring and removal of the AR would cause it to jam so often. The only theory I have is that when I removed the AR, I may have removed some material that stopped the dart getting sucked back in the plunger but I have not really experienced this with any of my other modified blasters.

Any wisdom from the experienced members would be greatly appreciated.

I can upload pics if it is needed but am currently without camera atm.

Its probably your seal 'vacuum loading' the darts. this happened to all of my raiders and I needed to get a smaller O-ring. I think I got mine from a recon.

Hmm, yeah, 'vacuum loading' seems about right to me.

Wouldn't putting a smaller O-ring in make it less powerful though?

Would it be worth trying to add something to the plunger to stop the dart from being able to be sucked in? Has anyone tried this?

yeah, i would try to stop the vacuum loading by placing an object which will not hinder the airflow, into the plunger system, say epoxy a small ring around the end of the plunger, where the AR was previously? i know that in homemades, people often place a thin piece of wire there to stop just that happening.
cheers