BBS spinning up with No Hop on

[ReconRabbit]

Hi guys I bought a mp5k off here a jg one got it, decided to have a mess around in the garden charged my battery's only to find I could not hit my target as the bb would spin up just before it got there, the previous owner said he changed the hop rubber about 6months ago and that it had not been used much since.
My target was around 15-20ft away and I'm not sure what's going on the hop arm is set to normal as far as the Manuel tells me and even if i move it half a cm to add hop it spits out the BBS with very little power at all

I haven't taken it apart yet was hoping someone would be able to tell me what I should be looking for?

Do I need to replace the hop up unit? Or even the rubber?

And help would be fantastic
Thanks
Rabbit

[Figjam]

Re: BBS spinning up with No Hop on

I've had three different scenarios causing this in the past.
1) some obstruction on the hop arm pushing the arm down even when you have the dial wound all the way down. This was in an M4, and I can't envisage how that'd happen in an MP5K, but thought it'd be worth mentioning, see if there's anything like a wire or whatever in there.
2) The nub is too big or has turned on its side in the unit. Try disassembling the unit to see.
3) The hop rubber has gone hard. This can happen with long periods of disuse. I call it left in a cupboard syndrome. I have a couple of mates that get to skirmish maybe once or twice a year, and their hop rubbers have had this once or twice. I've also bought a couple of guns that have come with this problem. Take the hop out and look down the barrel with the hop all the way off, if there is still a bump pushing down with nothing pushing to cause that bump, the hop rubber has gone hard. They talk about washing it in warm soapy water and I've also heard talk about silicone oil on the outside to rejuvenate a stiffened bucking, but neither have worked for me, but YMMV.

[ReconRabbit]

Re: BBS spinning up with No Hop on

Cheers figjam I'm just trying to work out how to get the upper off the lower at the moment won't jus slide off like my SD does there's a fuse housing in the way even with this taken apart cantcseem to get the wires to pull though,
So what's the best grade hop up to use in one of these anyways?

[Figjam]

Re: BBS spinning up with No Hop on

If its anything like the TM mp5k you'll have a couple of little battery connectors you want to pull out from the back after you've taken the pins out, and then you want to pull the lower backward and kinda down. As for replacing the hop... lots to take your pick from. Personally I've had great results from Guarder and Firefly, but there's newer on the market (and actually in my bits drawer) that I've not tried yet. I have a couple of PDI W holds that I keep meaning to try out based on a recommendation (from Ben off here I think), but ATM all my AEGs hops are in the ain't-broke-don't-fix category.

[ReconRabbit]

Re: BBS spinning up with No Hop on

I can't seem to see any I'm watching YouTube video but they all seem to be a bit different lol

[Figjam]

Re: BBS spinning up with No Hop on

90% of all youtube tech vids now seem to be 12 year olds. If I have the patience I play the game of seeing how far in before they go "oh, that wasn't supposed to happen" as they obviously wreck their gun.

[ReconRabbit]

Re: BBS spinning up with No Hop on

Yh Iv heard that before noe lol iv looked down the barrel with a torch and seems that that hop rubber is sticking though quite a bit and I'm guessing its dried out now just need to work out how to get in there and put it right,

[ReconRabbit]

Re: BBS spinning up with No Hop on

Thanks for you help figjam gonna give up trying to get in until iv picked up a new hop rubber and possibly a new barrel too all tho I did push my unjamming rod down there with some silicone on it ill see in the morning if that's made any difference too dark to check now

[ReconRabbit]

Re: BBS spinning up with No Hop on

I gave the barrel a good soaking with silicon oil and ran my unjamming rod down to dry up the excess and now its dipping at 30ft as it should with no hop lovely stuff

[Figjam]

Re: BBS spinning up with No Hop on

Hopefully that's the end of it. How is the FPS?

[ReconRabbit]

Re: BBS spinning up with No Hop on

Not to sure as I don't have my own chrono yet anyways but its hitting my target consistently now straight and true with .25's all tho I'm more likely to run it on .2's just ain't got none ATM

[Colonel Kurtz]

Re: BBS spinning up with No Hop on

I had similar occur to me, turned to that the hop rubber wasn't on the end of the barrel properly, and was creating an elipse. It was initially bad enough to create mis-feed, so like yourself i gave it a barrel clean without dissassembly. this managed to push the rubber into position enough that it stopped misfeeding, but gave a similar spin result as you described. When i took it apart i found the rubber was't on properly. As JG is terrible build consistency (clearly no checking done in factory) I'd recommend taking the hop-up apart and ensuring the rubbers on properly, dont want to impregnate anyone.

[ReconRabbit]

Re: BBS spinning up with No Hop on

I can't seem to get the upper off the lower bud wires won't fit though, but I'm due to take my ICS mp5 SD to mikes crazy customs for a rewire and to change a few parts so might take the mp5k and have it looked at possibly change a few parts in that aswell, and the hop rubber was changed by the previous owner bud so I recon its on OK just dried up as he given up the sport and was stuck in a cupboard for 6months as for impregnation iv got 3 kids lmao

[Colonel Kurtz]

Re: BBS spinning up with No Hop on

Yeah probably just gone hard (giggity) over those 6 months.

I feel your pain in taking apart a JG, the broken M4 i got given had a fricking car-fuse in it, and cheap bolts used instead of screws in alot of the receiver.

[ReconRabbit]

Re: BBS spinning up with No Hop on

Lol yh my ICS mp5 is lovely to take apart two pins thing slides into two parts this jg is welded together I'm sure of it lol