Ruger Air Hawk

[jfrey]

Ben,
You won't get any flames from me.   I clearly remember looking at my loose piston shaft and thinking "this could be a very desirable situation" for all the exact reasons you mentioned.

Ultimately I decided to heed advice from Pappa and Mikeiniowa and have it welded, as mentioned here :     http://www.gatewaytoairguns.org/GTA/index.php?topic=43150.0   

John

[avator]

Hmmmm, altho I don't have Airhawks anymore because I sent them off to Mike, I had them both apart twice. Once for original cleaning, lubing and deburring when we first got them and again after I got the tophats from Mike and did the sleeve reversal mod. I honestly don't remember either one being loose. I would think I would have noticed. They both shot very well before and after the tunes. The difference was the smoothness from the mod. I am also sure that Mike will take them to the next level with his expertice. I don't know what he plans to do with them but I do know they are going to make someone real happy. They just didn't serve our purpose because Betty Lou's was a bit too much gun for her. If were not for that fact, I would have kept at least one of the Airhawk. I have the Beeman Silver Kodiak and the Nitro Venom for when I get the big gun urge. Also, replacing the Airhawks with the XS-12s fits our program perfectly. I'm not justifying, just stating facts pertinent to us. But again, I don't recall either one being loose.

[pappa]

From all that I see here, I believe that there may be a problem with the cross hatching that was done. What is the grit of the stones used? Anything coarser than 400 grit is way too coarse and that leaves a finish in the piston seal area that wears the seal out WAY too fast. Most brake hones come with a stone grit of 350 or worse. I always install finer stones on a hone before anything else happens. Also, crosshatching should be done relatively sparingly. If overdone, you are just cutting away on the most critical area of the  compression chamber. Also, was the cross hatching area thoroughly cleaned of all honing residue with a good scrubbing with detergent water, well rinsed and dried, and then coated with a good layer of 60+% molly grease and was the seal and piston also coated with Molly grease before being inserted?

Another thought on buying a good airgun based mostly on price. I had a brief discussion on this with someone here in my review of the Air Hawk on Amazon.com. I have purchased 2 Air Hawks from Wallyworld and they have both been bad in almost every way and I sent them both back. I have purchased 4 from Amazon.com at $99.98 and they have all been absolutely factory perfect as received. All I ever had to do to them is a basic tune-up for delivery to customers that have been very happy with what they received. I am convinced that Wallyworld is selling questionable stock from a warehouse that deals in aged, neglected stock that is not first rate.

Just my $.02.

[TooJung2Die]

Pappa, I think you're right on the money with the hone grit question. Don't know what grit this Harbor Fright hone has. I didn't hone for long, less than a minute and what I thought was just enough to score the surface. Based on how much the seal was worn down in a short time, it probably has stones that are too coarse. Others have said they used them successfully but HF tools are not the highest quality and can vary. I used Dawn in a sink full of water as the medium, blew it dry with compressed air, then wiped out the cylinder until the rags came out white. This has worked for me before with OEM Crosman seals. This is my first go with Vortek parachute seals.

I don't use JM moly grease on the piston seal or cylinder walls anymore. Like many others, I discovered Krytox lube. Extremely durable lube and no detonation from the first shot.

I sent the first Wally World Air Hawk back because it had a rusted, poorly rifled barrel. I never even got to the point of opening it up. The second one they shipped me got lost in transit. The third one, this one, is much better. I'm satisfied with how it is turning out so far and it is a great learning platform for when I decide to tune up the Diana 34.

Jon

[pappa]

TooJung2Die,
Harbor Freight stones are 350 grit at their very best. I usually cross hatch the front end of the compression chamber for about 30 seconds at a VERY slow spin. Haven't had a failure yet. My stones are 420 grit. Tried Krytox and a couple of other synthetic lubes but always go back to Molly grease. I have enriched mine to about 70% molly and it always does what I want it to and I have NEVER had a problem with detonation or smoking. On my own Air Hawks (and D34's), I have put several thousand pellets through each of them and they are still shooting as accurately and strongly as when they started. I'll stick with the molly grease. It is certainly a well tried, reliable and true lube for what I use it for.

For what it's worth, for all of my Ruger and RWS rifles, I only use Vortek black seals and I have never had a failure or lack of performance with them. All my own custom main springs are also Vortek .130 wire. Performance power is OUTSTANDING!!!

Why do I do all of this? I live at the end of a long cul-de-sac in a very green and heavily treed neighborhood in North Carolina. The squirrel population used to be  tremendous and was driving everyone on the street nuts. My wife also feeds a large population of birds with feeders and furnishes bird baths for them and the squirrels used to drive her nuts by raiding the feeders and washing themselves in the bird baths.That was 5 years ago and now there is hardly a squirrel that can be found in this neighborhood. One of my next door neighbors is a canine cop with a large German Shepherd  and I occasionally toss the dog a squirrel just to play with and bury. No worries, I get along with the cop very well. My only real worry now is that for the last 2 years in a row, I have run out of squirrels by the end of spring. Dang; life can really get tough sometimes!!!

[TooJung2Die]

TooJung2Die,
Harbor Freight stones are 350 grit at their very best.

Anyone out there want a used China Fright brake hone? Good condition but the stones are a little on the coarse side. 
I use a short piece of fuel line tubing and a drill bit to extend the shaft. If a stone were to catch the rubber tubing kinks and doesn't break the stone. Turning the hone as slowly as the variable speed drill will allow. I'm buying a quality brake hone with a known grit.

For what it's worth, for all of my Ruger and RWS rifles, I only use Vortek black seals and I have never had a failure or lack of performance with them. All my own custom main springs are also Vortek .130 wire. Performance power is OUTSTANDING!!!

I'm very happy to hear you like the Vortek black seals 'cause that's what I have in there now after ruining the red seal. The black seals are softer and supposed to be more forgiving of uneven compression tubes. When the time comes I'll certainly keep your spring advice in mind. The Air Hawk has .128" wire. They must be jack hammers with the heavier .130" wire spring.

Big Question - How do you size your seals? By measuring the diameter or by feel in the compression tube? I've asked this before and no one has shared their secret.

Jon

[pappa]

Jon,
I don't understand your question about 'sizing' a seal. If you are buying a seal for an Air Hawk, for instance, any manufacturer or dealer providing seals for that rifle will know what the 'size' should be and provide it to fit THAT rifle whether it is from Vortek, Flying Dragon or Umarex, etc.

On your statement about stone grits, you don't particularly have to replace the entire hone to change the stone's grit. In fact, that is the most difficult way to accomplish your goal since you might shop for days and days and never find the hone with the right stones especially since most hones don't even advertise their grit size. My hone came with a coarse grit set of stones and I simply went on Amazon.com, found the right grit of stones that I wanted and ordered them. All you have to do is remove the stones on your hone and put the proper grit in it's place. In my case, the new stone mounts didn't fit the hone so I simply removed the stone's from their mounts on each stone set (in my case, simple heat was enough to get all the stones removed), reshaped the stones with my Dremel grinder from the replacement set to fit the hone's mounts and glued them on. Works like a charm and the new stones have honed dozens of rifles and still look and act like new.

PS. The best hone shaft extension is stiff plastic tubing, found in coils at Lowes or Home Depot, etc. in the plumbing department. It is super cheap and will last for years and years. Just take your hone in to make sure you get the right size.

[TooJung2Die]

Jon,
I don't understand your question about 'sizing' a seal. If you are buying a seal for an Air Hawk, for instance, any manufacturer or dealer providing seals for that rifle will know what the 'size' should be and provide it to fit THAT rifle whether it is from Vortek, Flying Dragon or Umarex, etc.

Claud,
When I put in the black seal it was very tight. Velocity was better but not as good as with the damaged original seal. I chucked it in a drill press and sanded .005" off the diameter. Now the velocity is back where it was.

I read many pro tuners talk about oversize and undersize compression tubes and "sizing" the seal for a custom fit. Jim Maccari says his seals need to be sized to work properly and tells how he does it but gives no advice on what size is correct. So I'm wondering how to tell when a seal is sized correctly for a compression tube.

Good advice on the hone stones. I'll get the fine grit stones and epoxy them to the hone I have. Nothing wrong with it except for the coarse grit. I think I'll continue to use the rubber hose until I'm an expert. I've had a stone catch and it kept the stone from damaging the tube or the stone.

Jon

[jfrey]

I read somewhere (likely here on GTA) some advice on fitting piston seals.     With the compression tube in a verticle position the piston should not drop to the bottom.   It should need about a pound or so off push to start moving, and come to a stop when the push is removed.       I recall fitting the seal with 600 grit sand paper until I was able to push the piston and seal down the compression tube with one finger.   Felt like a pound and that seemed correct to me - but I don't have a ton of experience fitting piston seals,  like Jon, would like to hear others methods.   

[pchunterpa]

Krytox lube, is there a product # for it

[TooJung2Die]

Krytox lube, is there a product # for it

Amazon or eBay. Look for Krytox GPL. 105 is oil and 205 is grease. Ultimox is another brand name for the same lubricant. Extrememly durable lubricant and it will not ignite. Ever. No more dieseling after a lube. Zip, zilch, nada. It's often used in high pressure, oxygen rich environments.

[pappa]

Krytox lube, is there a product # for it

Try just looking it up on Google search.

[pappa]

Error; Error, Error, Don't know why but the system stuck 2 of this message in, one after the other.

Certainly would be nice if this site would just give us the ability to delete our own entries if we made an error. etc!!!

[longhunter]

Certainly would be nice if this site would just give us the ability to delete our own entries if we made an error. etc!!!

then we wouldn't know who the screw-ups were  .

[TooJung2Die]

I don't have a ton of experience fitting piston seals,  like Jon, would like to hear others methods.

Hear the crickets?    Same response I got last time I asked. I suppose if ya hafta ask, ya wouldn't understand. 

Jon

[jfrey]

Jon,
Here's some more information for you,  and I was wrong.     Should be 2 lbs of force on a lubed piston seal.     According to the sources below (including Mr. Melick) who are relaying information from Gerald Cardew, author of The Air Gun From Trigger to Muzzle.

http://www.network54.com/Forum/79537/thread/1263242929/Piston+seal+sizing+question-----

http://www.network54.com/Forum/79537/thread/1294867106/best+way+to+size+piston+seal++----

http://www.network54.com/Forum/79537/thread/1111986548/1112032797/Springer+Tuners+-+Sizing+a+Piston+Seal...



Google  -  All the worlds information in the palm of your hand.......

[TooJung2Die]

Good examples, John. Thank you. I've been looking on the Yellow forum too. Mr. Cardew's book will be an interesting read. All I needed is the basics. There's a lot more to it that comes only with experience, of course.

[TooJung2Die]

Something else you'll notice not normal with knock-off guns. The scope ain't  all that bad for what it is.
Good luck, I hope you enjoy yours as we do.

I think the scope has bit the dust. The elevation adjustment on the Ruger 4x32 scope is wobbly and the detent is gritty feeling. Some times it doesn't want to turn. It wants to shoot two groups. One out of every three or four pellets hit high at 25 yards. Too bad, I kinda liked the scope for it's clarity and fine crosshairs. I put the Bushnell Banner on the Air Hawk and the double groups stopped. The droop adjustment made to the barrel must be pretty close because it took less than a half turn on the elevation to get the POI centered with the Bushnell.

This is my second Ruger 4x32 scope. Like the other one, this one may find a home on one of the MSP airguns. I've been thoroughly enjoying this project. I have a Vortek PG2 kit coming! Now I'll get to see first hand why so many rave about this kit.