Hammerli AR20

[bigHUN]

I just pick it for very cheap from a friend of my, he got tired of the leaking problem and I know for sure he have no PCP compressor. Otherwise the overall cosmetics is not so impressive as well.

First comes to mind to replace all the orings without checking, this is a several years old airgun and he is saying last time he was shooting with about 2-3 years ago.

He gave me also a FT regulator but as parts in a box and some belleviles may be missing.

Searching now for the drw/diagram also a BOM.

Any thoughts where to start refurbishing this airgun I know nothing about?

 

[d3vnull]

I was curious about this rifle and poked around some. Here is what I found:

Washer stack:

https://www.airrifle.co.za/threads/34948-Hammerli-AR20-regulator/page2

http://www.airgunbbs.com/showthread.php?741289-Hammerli-AR20-Regulator-Diagram

Turn sub-titles on:

https://www.youtube.com/watch?v=u-aw8tUtchI

Diagram:

https://www.airrifle.co.za/library/Haemmerli_AR20_ET-Liste_2793008.pdf

http://firearmstraining.ca/Hammerli_AR20.pdf

 

[bigHUN]

I got this AR20 for less then the .177 Impact liner kit could cost me, looks like I have a winter project.

I need to open the regs to measure the washers and order some, also orings to put on the order as well.

btw, how Hammerly is measuring the orings, by OD or by ID? (meaning by european, american or asian practice/standards)

 

[gonzav71]

When my AR20 leaked air, I replaced this O-ring with a 12x2 O-ring.

 

[bigHUN]

Last night I toke it apart partially only, and seeing that oring you pointed to (12x1.5) is some hard material, more like a plastic ring vs a rubber oring, already started disintegrating.

Ordered a full set of BUNA 90 orings from that your same BOM.

In mean time I will have to figure out how to separate the valve cap most likely I will have to use a torch to make the thread loose.

 

[scotton]

I'm watching this with interest. Here is a little gift for you. I did some pellet testing of my AR20FT today. My go-to pellets for this gun are the Air Arms Diabolo Field 8.4 (4.51 diameter at about 762 fps with the LDC on). It also shoots the Air Arms Express, the FX 8.4 and the JSB Exact and Express pellets well. All shots were off a bag at 25 yards with very swirly crosswinds of about 8 mph. Usually the Air Arms Fields will one hole at 25 yards, so not the best day for pellet testing. Also, this is the only gun that I have that shoots the RWS Superdome with any kind of accuracy. So, long story short, accurate gun, not very pellet fussy. I would start with either JSB Exacts or Air Arms Diabolo Fields at around 451 diameter.

 

[bigHUN]

Last night I started replacing the orings in the Regulator and wanted to separate the Valve cap as well,

I have no spanner so improvised with two dowel pins clamped in a vise.

Heat up the cap with a small torch to loosen a decade old loctite (and most likely not enough heat) and as I applied a force to un-screw, just happened to broke one of the dowels.

Ended up with a bent Valve Pin and still the cap is sitting tight. "Well designed" piece of old junk.

I can try one more time to heat this thing up with a bigger torch but a bent pin is a damage bigger then looks like, may brake easily if I would touch it to straighten back.

This is emotional...looking everywhere on the web for a new - full Regulator assembly or eventually for Valve Pin only, no luck.

Can anybody point me to a secrete source for this part?

 

[gonzav71]

I have a spare AR20 regulator but it is the higher power version 23J (17 FPE) part no. 466.62. You get only 25 regulated shots out of it with the steel cylinder.

I am willing to sell it for $60 plus shipping. I see you are in Canada. However, there might be laws against buying parts that are for air guns higher than 7.5J power.

 

[bigHUN]

I have a spare AR20 regulator but it is the higher power version 23J (17 FPE) part no. 466.62. You get only 25 regulated shots out of it with the steel cylinder.

I am willing to sell it for $60 plus shipping. I see you are in Canada. However, there might be laws against buying parts that are for air guns higher than 7.5J power.

I buy it with paypal. Pm-ing you after this txt below.

I have an Impact (and I have a RPAL license for restricted guns) and was buying parts from US before.

For your own piece in mind I will send you my license picture as well with the exchange. Whoever may ask you for it they already know what it is.

 

[bigHUN]

and btw, time is up me to learn how to talk in jules.

Just calculated it, aha , my .25 Impact is 94.91 joules at this setting.

 

[bigHUN]

This conversation was really educational. Turns out I have no clue how to use joules, and I would need a 7 joules Reg.

Unfortunately I need to step back from this deal but THANKS for your effort and patience with me

 

[gonzav71]

Contact UmarexUSA. Order a new 7.5J regulator (part number 466.60). Or post a Want to Buy ad on the Classifieds forum. Someone should have one out there to sell.

 

[bigHUN]

Thanks, I sent out several emails to US and EU stores selling sporting air rifles, just waiting for people to get back to their computers.

 

[bigHUN]

I got a bit of pissed and toke a bigger torch and finally managed to brake the seal on the cap

happy now, replaced all the orings to BUNA90.

Question:

1.) Shall I put a red loctite back again on the Valve cap? or suppose to seal alone on that green oring?

2.) I am seeing 2 part numbers on the diagram but those 2 parts are not in this my Reg, also not in the youtube video above:

3.) Anybody experience with gas lines in the basement? Can I use that epoxy to seal the Valve cap with the body?