hw97k cocking arm pin fix

[EMrider]

I shoot my hw97k often.  It is my favorite and most accurate springer.  But all of the shooting caused the gun to develop some problems with the cocking arm pin.  Specifically, the pin worked itself loose and developed some play in the cocking stroke.  This is part number DP093 in the hw97k parts diagram. 

After replacing this part twice with a spare purchased from Chambers in the UK, I continued to have problems after a tin or two of pellets.  The pin was not tight enough to stay in place and eventually it worked itself loose. 

A few searches indicated that while not a common problem, others have dealt with this issue before.  A suggested fix was to purchase a 5x10mm shoulder bolt from McMaster Carr. 

This is a very robust fix that has worked well for me.  If you encounter any problems with part DP093, I'd suggest using the McMaster Carr fix instead of buying a replacement part.

Here is a link to the specific part number:

https://www.mcmaster.com/nav/enter.asp?partnum=90323A325

You will also need a small hex bolt, part number linked here:

https://www.mcmaster.com/nav/enter.asp?partnum=90710A035

The fit in the stock is snug, but there is enough clearance if you trim off some of the bolt threads with a dremel tool.

R

[EMrider]

DP

[bustachip]

A few searches indicated that while not a common problem, others have dealt with this issue before.  A suggested fix was to purchase a 5x10mm shoulder bolt from McMaster Carr.
This is a very robust fix that has worked well for me.  If you encounter any problems with part DP093, I'd suggest using the McMaster Carr fix instead of buying a replacement part.

I haven't heard of this problem before, at least with my 97/77 the pin in the cocking arm remains tight, and
I have removed and replaced them on both rifles several times. I think that pin has some taper to it and should only go in from the left side if I remember right.

Sounds like you found a fix for yours though, show us a pic of your new pin in the rifle?
Now all ya have to do is make sure the nut doesn't come loose?

Regards, TMurray



 

[Jason_Garvin]

None of mine have done this yet either.  I wouldn't hesitate to stake the pin from both sides if needed.  Also, you could acetone the holes and dope them with Vibratite VC3, I use this on everything airgun with excellent results.

I read the same on the pin, and curiosity got the best of me.  And the last 97 I had open I measured the pin, and mine was straight as an arrow?  With no taper.

🤔

Jason G 

[EMrider]

A few searches indicated that while not a common problem, others have dealt with this issue before.  A suggested fix was to purchase a 5x10mm shoulder bolt from McMaster Carr.
This is a very robust fix that has worked well for me.  If you encounter any problems with part DP093, I'd suggest using the McMaster Carr fix instead of buying a replacement part.

I haven't heard of this problem before, at least with my 97/77 the pin in the cocking arm remains tight, and
I have removed and replaced them on both rifles several times. I think that pin has some taper to it and should only go in from the left side if I remember right.

Sounds like you found a fix for yours though, show us a pic of your new pin in the rifle?
Now all ya have to do is make sure the nut doesn't come loose?

Regards, TMurray



 

I put some blue loctite 242 on the threads to keep it in place.

My hw97k has probably been taken apart 10-15 times because I like to tinker with springers and try new spring/seal/spacer combinations.  No doubt that contributed to the pin coming loose. 

I'll read the instructions and try to post a pic.

R

[bustachip]

I read the same on the pin, and curiosity got the best of me.  And the last 97 I had open I measured the pin, and mine was straight as an arrow?  With no taper.

  LOL....maybe it was the pins that hold the trigger cassette in? I could've swore some of those pins had a
slight taper...oh well, I only remove and replace them from the same side every time, and I mark he pins with
a sharpie so I put them in the the same way . Seems to work for me, mine are still tight....LOL.

Regards, TMurray

[Jason_Garvin]

I still do the same thing Thomas, try to punch it out the same way and back.  I always wondered how many times a guy could punch the pin before it would loosen up?  If mine ever start acting up I will probably just peen them on both ends like dovetail rifle sights,

🎯

Jason G