TargetTalk

Hi-
I have a mid 90's Hammerli 480, original owner. It seems to have developed a leak. I've looked at the manual and exploded parts diagram and it doesnt show the particular part thats leaking. If I go directly forward of the trigger, on centerline with the air cylinder, there is a small circular raised black ring, about 2 mm in diameter. It leaks from there.... My guess its some sort of safety vale for the cylinder. I can hear it slightly hissing, and in a day or two the cylinder is completely empty.
Otherwise it shoot fine (except it has always been a bit loud for my taste).

Any ideas on what to do? thanks!
Tim

Redwagon wrote:Hi-
I have a mid 90's Hammerli 480, original owner. It seems to have developed a leak. I've looked at the manual and exploded parts diagram and it doesnt show the particular part thats leaking. If I go directly forward of the trigger, on centerline with the air cylinder, there is a small circular raised black ring, about 2 mm in diameter. It leaks from there.... My guess its some sort of safety vale for the cylinder. I can hear it slightly hissing, and in a day or two the cylinder is completely empty.
Otherwise it shoot fine (except it has always been a bit loud for my taste).

Any ideas on what to do? thanks!
Tim

I noticed the same thing on my 480 regarding the parts diagram. I think that's part of the regulator...... mine is white/opaque plastic and not black. See pic

Years ago I had the black part (pressure indicator) that you mentioned, completely fall out of the gun. Before Hammerli folded (about 2003) I sent it back to them. They converted the gas system of the 480K to an AP40 system including installing an AP40 junior tank with built in manometer. The different tank and the hole were the pressure indicator used to be are the only visible external differences.

About 6 months ago a leak developed. I replaced the tank seal but that did not fix it. I sent it to Larry Carter who reported putting three internal seals in it which did fix the leak.

The Hammerli 480 K is one hell of a great Air Pistol

In addition to Larry who did a good job on this repair I've purchased tank seals from Cibles in Canada. They seemed to know their stuff as well.

Does anyone know how difficult it is to replace the seals in 480K tanks? The MIT team has about 8 dead tanks, and my plan has been to ship them all off to Larry's once the collegiate season is over. I know Larry is constantly backed up with repair work, so fixing them ourselves would be an attractive option.

I have a shop at home, and could make special 2-pin spanners to fit the tank ends, but I have no idea what to expect inside. The Hammerli info I have doesn't show any details of the inner workings of the tanks. I'm assuming there is a seal for the end caps, and then a valve seal on each end.

If I were in your shoes, and I have been, I'd contact our host: www.pilkguns.com and see if they repair your model Hammerli air pistol. I have had very good service from them and my experience goes back many years to very recently.

Thanks for the thoughts!
I'll try Pilk. I've tried calling Larry's a number of times with no answer, and email hasnt been returned yet. Hopefully they can catch up sometime!
Tim

From experience, I'm sure you'll prefer Pilk's service.

doughert@ptd.net wrote: I've purchased tank seals from Cibles in Canada. They seemed to know their stuff as well.

Tank seals or pistol o-rings that contact the cylinder? How did you get the cylinder apart to replace the seals? Did you make a spanner wrench for the end cap removal?

To install the O ring there is a conical tool that allows you to slip it over the end of the tank. I've never tried with the other tanks

doughert@ptd.net wrote:To install the O ring there is a conical tool that allows you to slip it over the end of the tank. I've never tried with the other tanks

The 480 cylinder has a recessed valve with no exposed o-rings. There are two o-rings on the stem that sticks out from the gun. I have replaced those w/o an issue & yes, a conical o-ring installer would have been handy, but for the 480, I am looking for the spanner wrench to turn the end of the cylinder off to service the inner o-rings, or to just see inside and see if something has blocked the valve.

On my 480 (fixed cylinder), it looks like some sort of small o-ring there at the read end of the tank.....just forward of the trigger. ANy way I can replace that? Its what is leaking.

BTW, I havent had much luck from Larry's, Pilk, and have email in to Umarex and the folks in Canada.......no path yet on a repair.....

tim

Pics of my 480 with o-rings are attached ... It is a 480 with removable cylinders. I bought it new with one cylinder at Camp Perry in 2002(?) from Neal Johnson Shooting Supply. I bought a second cylinder(red) from Larry in 2005 when he had extra new ones for sale(no longer has any-I checked last week & got an answer back).

The original 480 had a large o-ring back at the gun under the cylinder "shroud" ... see pic. It also had a smaller, second o-ring either in the cylinder, or in the groove at the end of the "stem." Both o-rings were rather soft & were dark green(rear), lime green(front or cylinder o-ring).

I do not recall an o-ring being inside the new cylinder of my 480 from Larry.

In my work, I work with & have worked with lubricants, industrial filtration for gas turbines, scuba air lubricants, food grade lube, rubber products, gaskets, seals, conveyor belts, hose etc .... From this experience I have seen o-rings get destroyed from improper lubricants, placement in improper pressure applications etc .... I deduced that the "lime green" o-ring that was found in either the end of the cylinder, or in the o-ring groove at the end of the pistol stem was too low of a durometer(soft & squishy) and the high pressure of the cylinder actually permeated the o-ring material and made it self-destruct internally(explode). The larger, dark green o-ring was made from similar material, but had a little higher durometer. Something made it shrink, become harder(non-compatable grease or lube?) and lose it's structure. I found some replacement o-rings at a local industrial distributor that sells bearings, o-rings, hose etc ... I bought a selection of o-rings that exceeded the 200bar rating of the cylinder. Since these are metric grooves, I could not find a perfect match with off-the shelf Imperial sized o-rings, but I was able to achieve a tight seal and a good fit. I am able to keep full pressure in my one red cylinder from Larry. My original cylinder(blue) no longer holds air and it bleeds down within 30 mins from the gun-side valve.... when it is not on the gun. If it is on the gun, the gun-cylinder seal is good enough to allow for at least 130 shots. It even stays full overnight, but that is not recommended(re:Ruby & Art Fox). They suggest discharging the cylinder fully overnight.

I chrono'd the 480 and I found 26fps differential between full cylinder charge and the 105th shot (see other post). Many shooters have referenced that the 26fps differental is no big deal ...

I feel that in my original blue cylinder, the "displaced/exploded" lime green o-ring that is to be in the front of the pistol stem(or in the well of the cylinder) may have sent o-ring particles into the air stem valve section of the cylinder.....or .... there are similar material issues with the internal o-rings in the cyliner(if that is the case, then the cylinders must be cracked open and the o-rings replace, or the cylinders just pitched.)

What this means to you:
1. Look at your o-rings. If they are green I suggest throwing them out, but before you do ... take some measurements and head to your local industrial distributor or bearing house (not Grainger, MSC, Harbor Freight, Fastenal they won't have a clue).
2. When purchasing o-rings, get them about 30-50% smaller in main hole dia and 30% larger in o-ring material diameter so that as you stretch them into place.... they will stay there & be the appropriate dia.
3. DO NOT use steel picks or screwdrivers to remove/install the o-rings or you will scar the o-ring groove area and end up with a by-pass leak.... and you will be totally screwed. Use a set of plastic gun cleaning picks, they work quite well.
4. I have a few o-rings available and will send them to you for $5 ... this just helps defray the cost of the 10-pack o-ring kits I had to buy. As you install them, you will think that they don't appear to fit correctly, but they do work for me. They don't go on super easy, so plan on a few minutes and a few swear words as you install them. YOu may even launch a few and have to search your shop for where it went.

See pics and PM with any other questions. No, I'm not a 570 shooter, but I do get consistent air out of the piece and that's all that matters. It's up to you to do the rest ...

Note - The discoloration on my o-rings & stem that you see in the pics is just a little smearing from a very tacky lube made for scuba breathing apparatus ... DuPont's Krytox, or something similar - VERY expensive.... http://www.amazon.com/gp/product/B004AW ... 4HX73VNJ66

I have been using a silicone based o-ring lube that seems to work very well and is considerably less pricey:

http://www.mcmaster.com/#o-ring-lubricants/=glbnhn Part # 9463K33.

My experience with o-rings is somewhat more limited than yours but I've been using this on the Bun-N o-ring on various lab apparatuses (apparati?) as well as on the o-rings on my Morini AP and have not noticed any deterioration over the past year.

Roger

RandomShotz wrote:I have been using a silicone based o-ring lube that seems to work very well and is considerably less pricey:

http://www.mcmaster.com/#o-ring-lubricants/=glbnhn Part # 9463K33.

My experience with o-rings is somewhat more limited than yours but I've been using this on the Bun-N o-ring on various lab apparatuses (apparati?) as well as on the o-rings on my Morini AP and have not noticed any deterioration over the past year.

Roger

Silicone is a common o-ring lubricant. The problem arises when it is used on silicone o-rings. The silicone o-rings absorb the silicone(similar to h2o osmosis) and get softer, swell and gummy which may have been the problem with the Hammerli o-rings(my opinion).

You are correct, silicone on Buna should create no issues ... Buna o-rings are what I bought & use in the 480.

I was lucky enough to have a small tin of a product similar to DuPont Krytox, so I used it ....

NikNak,

Do you have the dimensions or part numbers for the o-rings you got? I have the gummy remains of the o-ring at the bottom of the stem (your photo shows it well) so I can't get measurements. Even trying to measure the width of the groove is tough....

I am sure I can find o-rings that would work if I know what size to get.

Thanks!

I had a 480 with a fixed tank that leaked. The only fix was to have it converted to AP40 tanks 8 or 9 years ago. My regulator has started leaking again. I have not got an email back from Larry as of yet either.

I am happy to own an IZH46 at this point.

I have not had much luck getting my (AP40 converted) 480 fixed. The best case I have found was to send it in, wait 10-12 weeks to see if they have the parts to fix it. I would be more chapped if I bought a new AP40 last year and got the same info. It would appear that there might be a new air pistol brand in my future as much as I like the way my Hammerli shot when it worked.