Hand Pumping Hammerli Air Tank

[Ray Dash]

I am looking to use a hand pump to pump up my Hammerli Pistol air tank. The pistol cam with a fill adapter and I had to buy a DIN adapter so I could attach it to my pump. Now for the newb question, once the tank is full I can't open the bleed valve on the pump or ALL the air in the tank will leak out so am I just supposed to unscrew the tank from the adapter? Will the tank being under pressure cause any problems to the tank threads do it like this? I know there is a special valve that is sold but I can't find it in the US.

[Gwhite]

You need to unscrew the tank a turn or two to close the tank valve. Then you can bleed it to take the pressure off the threads.

[m1963]

Hello- GWhite is correct.

Unscrewing tanks under pressure can damage the threads over time, though. Besides, the fill adapter Hammerli provides is made of steel and can gall, as well.

Try this, from Best fittings, for ease of use and peace of mind-

https://www.bestfittings.co.uk/shop/fil ... -adaptors/


Best regards
m1963

[Ray Dash]

Hello- GWhite is correct.

Unscrewing tanks under pressure can damage the threads over time, though. Besides, the fill adapter Hammerli provides is made of steel and can gall, as well.

Try this, from Best fittings, for ease of use and peace of mind-

https://www.bestfittings.co.uk/shop/fil ... -adaptors/


Best regards
m1963

Any idea if anyone stocks that in the US?

[m1963]

Hello-

Not to my knowledge, it is a product of their own design.

Best fittings is a really great, trustworthy, company. They offer a discount to first time buyers that usually covers shipping to the US. Plus, the price you see includes VAT, (UK tax) for which you will not be charged, if the item is shipping to the US. My last order arrived from the UK in about 5 days. (That was pre-Covid.) Do not let the fact that they are in the UK deter you.

Best regards,
m1963

[Ray Dash]

Hello-

Not to my knowledge, it is a product of their own design.

However, Best fittings is a really great, trustworthy, company. They offer a discount to first time buyers that usually covers shipping to the US. Plus, the price you see includes VAT, (UK tax) for which you will not be charged, if the item is shipping to the US. My last order arrived from the UK in about 5 days. (That was pre-Covid.) Do not let the fact that they are in the UK deter you.

Best regards,
m1963

Ok great. I am going to order because it seems like I have to unscrew the tank almost all the way and while it's under full pressure I don't think it's a good idea.

[brent375hh]

When I had my Hämmerli, I quickly learned the value of a dab of Super Lube on the threads to keep from galling. The difference is night and day.

[Ray Dash]

When I had my Hämmerli, I quickly learned the value of a dab of Super Lube on the threads to keep from galling. The difference is night and day.

That is exactly what I am doing for now

[seamaster]

Unscrewing tank from adaptor under pressure will damage threads. Is this a fact or myth?

If that is the case, wouldn’t that happen to pressure release valve thread on hand pump, too? Making it leaky, harder to completely close that valve over time?

[Gwhite]

Unscrewing tank from adaptor under pressure will damage threads. Is this a fact or myth?

If that is the case, wouldn’t that happen to pressure release valve thread on hand pump, too? Making it leaky, harder to completely close that valve over time?

It's a fact, but how fast it occurs depends on the thread & fitting geometry, lubrication & dirt. Hammerli AP40 cylinders have a fine thread, and without care & lubrication, they can wear over time to the point where the threads can fail & launch the cylinder.

My Hill pump pressure release valve is showings signs of this. The release valve is much smaller area than the tank fitting, so the force is low, but it's still wearing slowly over time. I would hope the factory greased it, but I haven't checked. It's pretty easy to replace as long as you can get the part.

[Ade C]

Hello- GWhite is correct.

Unscrewing tanks under pressure can damage the threads over time, though. Besides, the fill adapter Hammerli provides is made of steel and can gall, as well.

Try this, from Best fittings, for ease of use and peace of mind-

https://www.bestfittings.co.uk/shop/fil ... -adaptors/


Best regards
m1963

Yes, get one of these. I hated filling mine till I got one

[Ray Dash]

If these tanks were cheap I wouldn't bother worrying about the threads but for the price of these tanks I ordered one of the fill adapters just to be safe. Thanks for the info.

[Ray Dash]

When I had my Hämmerli, I quickly learned the value of a dab of Super Lube on the threads to keep from galling. The difference is night and day.

How often do you put the Super Lube on the threads?

[seamaster]

I have two Steyr adaptors. So now, curious in doing a “drill through” on one of them.

Seems like a not too hard thing to do with a triangular file.

I assume file will be not all the way, but how far up?

[seamaster]

In the past, I have been unscrewing straight from the adaptor.

But I grab the adaptor-cyclinder tank area tightly with my left hand while unscrewing with my right hand. I felt grabbing hard provided some thread pressure stability, and more importantly, my gripping hand acted like a pressure reducing valve.

Have been doing this for a few years now because my Hill pump pressure release valve over time kept leaking and hard to close.

Was not aware of this drilled through thread bestfitting before. Will go that way now.

[brent375hh]

When I had my Hämmerli, I quickly learned the value of a dab of Super Lube on the threads to keep from galling. The difference is night and day.

How often do you put the Super Lube on the threads?

I put a little bit on the thread about every 5th or 6th filling.

[m1963]

They have one for Steyr air pistols, as well. Our daughter uses it for her pistol. She just put the original away, in the event she would ever sell/trade it.

https://www.bestfittings.co.uk/shop/fil ... l-adaptor/

[McMadCow]

When I had my Hämmerli, I quickly learned the value of a dab of Super Lube on the threads to keep from galling. The difference is night and day.

How often do you put the Super Lube on the threads?

I put a little bit on the thread about every 5th or 6th filling.

I use automotive anti-seize, the stuff you put on spark plugs. That stuff lasts a bit longer I think, and I do it every 10-12 fills.

[brent375hh]

When I had my Hämmerli, I quickly learned the value of a dab of Super Lube on the threads to keep from galling. The difference is night and day.

How often do you put the Super Lube on the threads?

I put a little bit on the thread about every 5th or 6th filling.

I use automotive anti-seize, the stuff you put on spark plugs. That stuff lasts a bit longer I think, and I do it every 10-12 fills.

The stuff I use on my spark plugs is silver, and gets all over everything, and is nearly impossible to wash out. I don't know it behaves with o-rings.

[McMadCow]

The stuff I use on my spark plugs is silver, and gets all over everything, and is nearly impossible to wash out. I don't know it behaves with o-rings.

True on all counts, and I keep it away from o-rings. But it sure does keep the threads silky smooth.