Few Questions about GBB's

[Boomshakah]

hi, my friend recently bought a KJW M92F, and before it arrives, we were wondering what special care does a GBB need. I'd like to get a confirmation of some things.

First, he bought a Madbull propane Adapter with silicone reservoir, he bought this oil : Silicone Oil 100% To put in the adapter reservoir. Good or not?

Also, we have read about KJW's mags leaking, is it hard to fix a leak?

And, to store the gun, is it true we have to leave a bit of propane in it to keep the seals lubed with the silicone in the mix?

also, what is the minimal temperature outside for shooting a GBB?

Finally, any special care he need to do to the gun before shooting and before storing?

Have a nice day all

[coach]

Madbull adapter will do fine. 100% silly oil is perfect.

Depends where the leak is, it's not difficult. Preventative maintenance is best. Keep some propane in mag to store as well as lube regularly. Avoid storing dry for prolonged periods. A silly oil bath will sometimes revive the dried orings but it's better to avoid getting to that stage.

It's best to game it at 15C+ any lower and you'll see a significant drop in performance as well as capacity. GBB's are used in colder temps but with the assumption that it'll not shoot more than a few rounds.

Keep the GBB clean, lubed and fed with good BB's and all is good!

[The Saint]

You're suppose to use a much lighter weight oil for the adaptor: http://www.airsoftparts.ca/store2/in...roducts_id=623

Mags are not hard to fix, it really depends on your mechanical aptitude.

Yes, store the mags with a bit of gas inside.

It varies from model to model, brand to brand. My own rule of thumb is to avoid using GBBs below 10C for plastic slides, 15C for metal slides. It's not that they stop working right at those temperatures, it's that they become unreliable, undependable and a liability during play.

Always wear eye protection, even when plinking. Make sure there is not a BB in the chamber before storing the gun.

[coach]

Originally Posted by The Saint

You're suppose to use a much lighter weight oil for the adaptor: http://www.airsoftparts.ca/store2/in...roducts_id=623

suppose to? suggested? recommended?

I've been doing fine with 25wt in GBB mags.

[Boomshakah]

Don't worry about gun security, we all know about. Thanks for this Info! but can we still use that 100% or i should buy the light one?

Also, whats up about taking a pencil for dry lubing moving parts? is it good or i should put silicone oil ?

[The Saint]

I'm just going to go with what's used by the person who invented the first propane adapter, if it's all the same to you.

[L473ncy]

The 1.5 wt is the lightest oil you can get. Apparently he needed to practically order an industrial barrel worth of it (and a barrel is more than enough for anyone in their lifetime). I know that to get this stuff the minimum orders are pretty crazy (like 1,000 T-shirts or 10,000 pens to get your logo on some swag except this is for industrial applications).

The 20 wt. is good but a lower weight oil is probably better. I use 10 wt. silicone oil in my GBB and that was from an RC hobby shop (the lightest RC shock oil that they offered).

Some people dump the mag when they're done (shoot until the gun can't shoot anymore making sure theres little to no gas left and use the dump button), some put enough for one or two shots and some keep it almost full. I personally keep enough for one or two shots and supposedly thats the best state to keep them in.

[Boomshakah]

Thanks Latency, well i guess we have to find oil more light then, but what it really does is only keeping the seals lubed? or it have a specific use wich provoque some chemical reaction with propane giving it some extra juice to spit that BB?

[Darklen]

Originally Posted by Boomshakah

hi, my friend recently bought a KJW M92F, and before it arrives, we were wondering what special care does a GBB need. I'd like to get a confirmation of some things.

First, he bought a Madbull propane Adapter with silicone reservoir, he bought this oil : Silicone Oil 100% To put in the adapter reservoir. Good or not?

A bit too thick for my liking. I use 10 weight and have no issues for +5 years now.

Originally Posted by Boomshakah

Also, we have read about KJW's mags leaking, is it hard to fix a leak?

Depends on where the leak is. If it's in the valve, orings are a bit of a problem. Mag base orings are a bit easier to service as the orings are a bit bigger.

Originally Posted by Boomshakah

And, to store the gun, is it true we have to leave a bit of propane in it to keep the seals lubed with the silicone in the mix?

Been doing that for +5 years with no issues to date.

Originally Posted by Boomshakah

also, what is the minimal temperature outside for shooting a GBB?

About +5C° or so you will notice a drop in performance.

Originally Posted by Boomshakah

Finally, any special care he need to do to the gun before shooting and before storing?

Other than keep the mag.propane lubed with silicone, not much. Keep a bit of gas in the mag and make sure the gun and seals are clean and lubed.

[Boomshakah]

Thanks everyone, its really apreciated

[coach]

Originally Posted by The Saint

I'm just going to go with what's used by the person who invented the first propane adapter, if it's all the same to you.

that's fine. I'm going by personal experience with 25wt and the countless mags that I know have been lubed with heavier oil over in a friends GBB vault.

[m102404]

This is just my own $0.02 and there's bound to be differring opinions...to each they're own, go with what makes sense and works for you.

PS. This question has been asked and answered at least 3 times in the past month or so...a search would turn up the results.

There's a couple of things that need lubrication in a GBB.
1. Bearing surfaces and contact parts that move
2. Seals

1. Bearing surfaces and contact parts that move
- rails, pivots, disconnects, sears, springs, plungers...all need to have a bit of lubrication so that they move/travel/reset nicely.
- guys have used MSO2 (molybendum-di-sulphide) grease, silicone grease, gear grease (usually contains graphite or teflon in a grease suspension), dry graphite (messy), white lithium grease, superlube (aka viperlube), silicone oil (various weights)

For bearing & moving contact surfaces I'd think that you'd want something "light" that will provide lubricity and "stick" to the surfaces you apply it to. In a GBB, grease won't really get flung around...but you'd want to avoid clumps/build up. In general, you'd want to avoid substances that will trap dust/dirt (and really fine sand)...which will turn it into a fine grinding paste.

Alot of bearing & moving contact GBB parts are metal. But not very good metal. They're made from either monkey metal (aka white metal, pot metal), aluminum or steel (and most times pretty low grade steel). Sometimes these parts are "chromed" to put a harder/smoother surface on them. Regardless, they need lubrication. Not a lot, just enough to do the job and no more.

2. Seals
There are a number of seals in a GBB system, typically:
- magazine bottom seal
- magazine top seal
- magazine fill valve seal
- magazine main valve (aka knocker valve)
- blow back unit piston head seal with nozzle
- nozzle tip with hopup rubber
- hopup rubber with inner barrel
- float valve with interior of nozzle
All of those seals need to seal repeatedly and consistently for your GBB to work. Most (I think the only common exception is the float valve) have an o-ring/rubber seal.

So...any lubricant that will destroy rubber (i.e. petroleum based) isn't going to work. Many of these seals are not easily accessible...so lubricant needs to penetrate and "seep" into these areas. Similar to grease trapping dirt...you really don't want a lubricant that will "attract" dust/dirt that will wear at the seal. Drop your GBB mag on the ground...pick it up and use it in your GBB and you've just blow any dust/dirt that was on it right through the whole system (not the end of the world...everyone's done it and nobody keeps their stuff in hermetically sealed NASA food ziplocks ).

So...what to use....?
- lightweight (1wt to <15wt) 100% silicone oil...that's a good easy one that can be mixed with propane. Used this way, the oil will penetrate throughout the mag and get blown up through the rest of the GBB. With every shot, escaping "oily" gas will typically deposit oil over the entire firing assembly and usually it'll get to the rails and other parts as well after a bit. It "evaporates" after a while...so that's good in that it's not picking up dust endlessly.
- lightweight (non-petroleum based) grease on pivot/springs/bearing surfaces...a little goes a long way.

Maintenance:
- keep your mags with a bit of "oily" gas in them...don't keep them full, anywhere from Full-5 shots to just a shot or two left (don't know how to measure that) is fine. If you shoot a lot (i.e. every day or several times a week) you probably won't have any issues with storing them empty.
- learn how to fully disassemble your pistol (not just field strip). It may seem daunting because there's a billion little spring and screws in them...but after a season you'll be amazed at the crud build up in them.
- field strip clean your pistol after it get's a good workout....that might be after a single game for you....or after a month of casual plinking in the basement. It is NOT like a real piston where it's filthy after each use.
- Store it safely. No BBs in the mag, pistol locked up in a locked case and stored out of sight. Keep a pair of shooting glasses (they're dirt cheap and easy to find) in your case if possible...then you'll never forget to put them on when you're shooting.

Again, just my $0.02...use your common sense. No matter how bad you screw it up, someone's already done worse.

Best of luck,

Tys

[Boomshakah]

Thanks alot, Tys, for this detailed reply on how to keep a GBB in good shape. Its really apreciated!

[Slono]

Tys's answer is going into my word document file of "How To"s for GBBs, hehe.

[coach]

to each his own. I'm just confirming that 25wt silly oil will work if it is needed to be used.