Vortek kit problem

[JayJay]

I ran into a problem installing a Vortek PG3 kit in my new HW95. The new spring assembly fits well into the piston and cylinder but takes high pressure to compress. I was just barely able to get the breech plug into the gun and assemble it. My spring compressor is a woodworking table and vise, it has good mechanical advantage.

Cocking effort was ridiculous, I didn't try to latch it to the trigger in case it would break something.

I reinstalled the original Weihrauch spring and everything works beautifully. The PG3 spring assembly looked none the worse for wear, no crumpled guides or scored parts that would indicate interference. I double checked the piston, saw no washers.

Vortek isn't answering their phone.

Perhaps they packed the wrong spring or the guides are too long? The PG3 spring itself is shorter than the original by about an inch. Wire diameter looks about the same. It's definitely much stiffer than the original spring. 

Any ideas would be appreciated.

 

[Deerstalker]

I believe that the spring for the HW95 should be 10 5/8", (10.63"), long. Did you measure your original spring? Was there a specific reason that you decided to replace your factory setup? Thanks

 

[JayJay]

The new spring is about 10 1/2" long. The original is about an inch longer. 

I bought the PG3 kit because I had previously installed a PG2 in my HW30 with good results. 

 

[Chuck-in-Ohio]

Did you remove the old top hat from inside of the piston before installing the PG2 kit?



That would account for the excessive preload, and it sounds like you are trying to cock the rifle while it is going into coil bind.

Tear it back down and I bet that you will find the original top hat or thrust bearing is still installed in the piston.

 

[JayJay]

You're probably right. I looked inside the piston and didn't see anything. But this is my first time inside the HW95. I'll check again. Will get back shortly...

 

[Chuck-in-Ohio]

You may have to smack it a few times to get the spacer out, sometimes grease glues them in somewhat.

Give the piston stem a sharp rap on your bench with the piston held vertically, piston stem down and it may help to dislodge any spacer or top hat.



You did remove the factory piston liner as well, correct?

 

[JayJay]

Hi, I put the Vortek back in and look what happened. Gadzooks! Obviously the piston liner was the problem. 

Is there a best way to pull the liner? Or just use a pair of smooth jaw needle nose. 

 

[jmiller]

There’s a video where Paul Watts demonstrates tapping on the piston stem with a hammer repeatedly to remove the metal liner. I was able to do it with a small screwdriver 

 

[Yo]

Exactly how much better performance is this supposed to add and what was wrong with the firing characteristics of the untouched HW95?

I ask this very important question because thousands upon thousands of readers probably want a good reason not to buy an HW95 if it's that terrible straight out of the box.

 

[JayJay]

Ok. So what haappened is the plastic spring guide got hung up on the piston liner when I tried cocking the gun. The liner cut a slice from the guide. 

The Vortek instruction only says "Remove all items: spring, guides, washers, thin metal sleeve (if any)." The piston liner (thin metal sleeve) is not obvious, that's why I missed it. Grrr...

I pulled the liner out with a small needle nose plier that has smooth jaws. The liner is like a spring pin, it has a slit all the way down one side. First use a very sharp tool to lift a corner. Then get the needle-nose jaw under the liner. Pull a little at a time, alternating from side to side. The liner is mild steel, not hard spring steel. If you mar it, you can probably bend it back. It's important to save the liner and original spring in case the Vortek spring ever breaks. 

With the liner out, the PG3 spring assembly went in with no problem. I'm not worried about the short slit in the plastic guide. Chrony testing shows .22, 14.3 grain Crosman Premiere hollow points are now running 727 fps @ 16.8 FPE at the muzzle. That's up from 15 FPE, about 12% increase. The twang is totally gone, just a rapid positive thud. Cocking is a little more difficult, not too much. Note that I also installed the Vortek piston seal.

The original gun was totally OK. Frankly, I'm not sure the 'twangless' shot cycle is that much better. It feels a little more sudden and brutal. I have a friend who tunes pianos, he really likes the traditional twang! You do get a modest power increase, but you'll never notice it. I did it mainly for my own education and to 'bond' with the gun. So I'm a happy camper. But I don't recommend it unless you're really handy and have a well equipped shop. Just finding smooth jaw needle nose pliers is mighty hard. 

 

[JayJay]

Hi, the stock HW95 is fantastic. I just like to tinker with my stuff.

 

[boscoebrea]

Evidently the Vortex kit was not the problem.

 

[JayJay]

The kit itself was not a problem, and I'm sure Vortek's service dept. would have quickly resolved the issue.

 

[Gear_Junkie]

JayJay,

Thanks for sharing your experience so that we can all learn from it. I can see a lot of people missing the liner. You could probably explain the situation to Tom and he would send you a new outer liner at a reasonable cost. If not, you could round off the ends of the slit portion just to ensure that the spring doesn't hang up on it.

Glad it worked out for you!

 

[jmiller]

The liner being visible in the cocking slot seems pretty obvious to me. Also easily removed if you just stick a small flat screwdriver underneath it through the cocking slot and pry/pull it out. 

Also, adding a top hat to the stock spring and leaving the liner in results in a pretty good shot cycle with reduced twang and about the same power(725ish with 14.3 CPHP’s), in my limited experience of one rifle.

 

[JayJay]

The piston liner is not obvious. I fiddled with camera position and lighting to make it show up in the photo.

I like that idea of adding a tophat to the stock spring and keeping the liner. The tophat would increase spring preload and power. But the Vortek kit has additional benefits.

Recoil involves the relationship between gun mass and projectile mass. A heavy gun reduces recoil. A heavy projectile increases recoil. The piston and its liner are a projectile. The liner and washer weigh 19.5 grams, or 300 grains, about equal to a large bullet. Think about it... in a fraction of a second the spring accelerates the 300 grain liner to a significant velocity, then slams it into the end of the cylinder. That should cause a couple of thumps. A lighter piston *might* give you shorter lock time. (disclaimer, I'm speculating here). 

The Vortek spring is about an inch shorter. That means less spring following the piston, effectively removing some mass from the projectile. A shorter spring has a higher natural frequency which might reduce the perception of twang, although I think the guides are pretty effective at that. 

Overall the Vortek kit gives you a shorter, stiffer spring, better spring dampening, a small reduction in piston mass and a more slippery piston seal. Theoretically you should get a slight increase in velocity/power, some recoil reduction and less twang. 

With this in mind I fired it some more. The twang is gone. The cycle feels faster, a focused 'bang' rather than a 'twang'. My piano tuner friend agrees it has less recoil although he preferred the original twang. The bang was a llittle disconcerting. Accuracy was not affected. Cocking effort is definitely higher. I'll see if I can measure that.

The PG3 kit has a stepped tophat. Rotating it adds spring preload which increases power a bit. That's next on my agenda. 

 

[JohnnyPiston]

Just to be clear, it was not a Vortek problem, but an installation problem from the end user (inexperienced) from not following the instructions provided. 

I guess I think differently from others; if it were in fact a "Vortek problem" I experienced I would have contacted the maker of the product directly for a Vortek solution. Phone busy? Send an email. Wait a reasonable amount of time for a reply. Give him every opportunity to help you troubleshoot, give guidance, and need be, make it right.

 

[JayJay]

Last installment.

I dialed the PG3 tophat up one notch. Pellet speeds did not change perceptibly. Oh well, so I dialed it back. 

Vortek's site says the HW95 PG3 kit gets up to 18.5 foot pounds @ 940 FPS with the H&N FTT green 9.56 grain .22 pellet. Yes, I got 18.4 foot pounds @ 930 FPS at the muzzle with the same pellet, whereas most pellets are in the high 16 foot pounds. That's a super-pellet. It delivered 9.7 foot pounds in my HW30. Amazing! The tradeoff is that it sheds velocity and power much faster.

One of the reasons I bought the HW95 is that it's like a VW Beetle. Design is top notch, It's been around a long time, parts and high quality kits like the PG3 are readily available and it's pretty easy to work on. That's a huge advantage of a springer over a PCP. And you don't need a pump!

 

[JayJay]

OK, I see what you mean about the liner being obvious in the cocking slot. 

 

[RodneyRichwine]

JayJay, did you try pulling the Vortek guides out of the Vortek spring for any reason? I've got a PG3 but with a steel outer guide and the rear guide and the top hat won't budge, I can spin the steel outer guide but it won't move up the spring at all, almost as if it's somehow connected to the rear guide. This is going in a .22 HW95 as well, but I wanted to clean the parts off and relube them. I'm afraid to use channel locks because the guides are plastic and the channel locks teeth will most definately eat into the guides.