Lubing Hop Up.

[Criff]

What's the best way to lube up the rubbing bucking of the hop up unit on a TM MP5-A5? I've taken the gun apart once for other reasons and can do it again, but I'm wondering if it's possible without major disassembly. Any help is appreciated, thanks!

[Skladfin]

why do you want to lube the hop up rubber? If it's already inside there, then it's fine. Lubing it actually makes the accuracy crap(because the hop up rubber can't apply optimal friction everyshot).

[FOX_111]

I'd try to keep the hopup as clean as possible. It does not require oil at all.
Same for barrel and piston interior.

[Criff]

Thanks alot for the replies.

Awhile ago I posted a thread about what I needed to do to my gun after having stored it for 3 or so years (Question about dry firing and lube. - Airsoft Canada). Someone told me that the rubber bucking in the hop-up unit would have dried out, so I took that as meaning I had to lube it. To add to that old thread the dry firing now comes randomly, mid magazine. A few consecutive shots will be dry, then I'll take the magazine out to find that they were sitting in the barrel or the feeding tube.

Shortly after posting that thread, I found mechbox.com and learned how to take it apart, which I did, and lubed everything (now with proper silicone) in the mechbox that needed to be lubed. I didn't do anything with the hop-up because I didn't know how to take it apart, so to this day I'm still under the impression that the jamming is caused by lack of lube in the hop-up unit.

Any ideas?

[Styrak]

Originally Posted by Criff

Thanks alot for the replies.

Awhile ago I posted a thread about what I needed to do to my gun after having stored it for 3 or so years (Question about dry firing and lube. - Airsoft Canada). Someone told me that the rubber bucking in the hop-up unit would have dried out, so I took that as meaning I had to lube it. To add to that old thread the dry firing now comes randomly, mid magazine. A few consecutive shots will be dry, then I'll take the magazine out to find that they were sitting in the barrel or the feeding tube.

Shortly after posting that thread, I found mechbox.com and learned how to take it apart, which I did, and lubed everything (now with proper silicone) in the mechbox that needed to be lubed. I didn't do anything with the hop-up because I didn't know how to take it apart, so to this day I'm still under the impression that the jamming is caused by lack of lube in the hop-up unit.

Any ideas?

Was the hopup rubber stiff/dry and if so, did you replace it?

[Criff]

Originally Posted by Styrak

Was the hopup rubber stiff/dry and if so, did you replace it?

I'm not sure if it was stiff or dry, I didn't replace it or do anything to it. How can I check?

[CDN_Stalker]

If the hop up rubber isn't lubed once in a while, BBs will plug up and not feed into the chamber (I've fixed dozens of guns on the field with just silicon oil). I lube mine every 6 months or so, upside down on your lap, drop or two down the BB feed tube, dry fire a few times to spread it around, and within a few mags it settles down and accuracy comes back.

On the flip side, I never lube the rubber on my bolt action sniper rifles, I actually do the opposite, I WASH (warm water and dishsoap, let dry and put in a clean bag) the oil off my sniper ammo so the friction is increased, allowing you to use less hop up setting, decreasing the interferance in the BB path down the barrel.

[ROAR]

I personally shoot a quick shot of silcone spray in my hopup before every game and spray a few BB's thru it before i begin. Ive never noticed the acuracy of my guns dimish by doing this. I have been told to dial my hopup back down after every game to lessen the stretching of the hopup rubber. You could after every game spray some in there so the hop up doesnt dry out and just clean it before every game with a barrel cleaner or by shooting some BB's thru it if your worried about it drying out and dont want to replace your rubber every season or two.

[arman]

Originally Posted by CDN_Stalker

If the hop up rubber isn't lubed once in a while, BBs will plug up and not feed into the chamber (I've fixed dozens of guns on the field with just silicon oil). I lube mine every 6 months or so, upside down on your lap, drop or two down the BB feed tube, dry fire a few times to spread it around, and within a few mags it settles down and accuracy comes back.

.

bingo thats what i do.

i figured its rubber and could crack or get hard, id rather have a few shots that were not as accurate than a cracked rubber

[CDN_Stalker]

Hop up rubbers are made of different materials, rubber (like the Madbull blue ones), silicon (I assume the Guarder clear are this) and other compositions. Haven't seen any hop up rubbers crack, mostly tear.

Interesting, I ran the chrony at the Mill game on Feb 28th and it was maybe about -15C outside, so inside the building was roughly -10C at the lowest, and out of the 40 odd guns I chronied, some sat normally, say decent 300-350fps, as one would expect to see, but about half to 2/3 of them I'd read much lower and varied fps, I think the lowest was about 175fps......... the owner was stunned because it's a 330fps gun, I said likely due to the cold and the type of material used for the hop up rubber, chances are nothing was wrong with the gun. And all guns were tested indoors at a distance of 150ft by those that shot lower than expected and the BBs travelled fine for distance. And yes, there were a couple cases of BBs plugging up (aka. not entering the chamber) in the hop up unit, a couple drops of oil cleared each and every one of them.

[Criff]

Thanks for all the replies. I sprayed a little bit down the feeding tube, dry fired a few times, then put a magazine through it and it seems to be working better. Only problem is the stuff I've been using lately which I though was silicone contains petroleum, I just read the side of the can. It says silicone 3 in 1, comes in a yellow aerosol can, and I got it from Home Depot. I also used this in my KSC USP and magazines. Is this really bad?

[arman]

uh-oh... you just made a boo boo... using petroleum with rubber parts is verry bad.

[yuhaoyang]

Petroleum dissolves plastic and rubber slightly, use only 100% pure silicone oil.

[Criff]

It does say safe for rubber on the can. Are my guns and mags going to be okay, or should I give up?

[Phil_Black]

Your AEG will be fine,

Just start using silicone oil for the next time you clean it.