HW97 tune story??

[Tomcat]

I got my .177 cal HW97 out a few days ago and decided to check it on the chrony.  It was down to around 10-11 FPE with any type pellet I tried.  Now this might have been a self inflicted problem, as I had buttoned the piston and the compression chamber quite a while ago, and of course made a new spring guide out of delrin.  If I checked the #'s then, I don't know where I recorded them (senior moment) .  I will have to look for that.

The spring and seal are factory, (I bought the gun new).  When I disassembled the rifle a couple days ago, I discovered the piston was perhaps too snug inside the compression chamber.  The way I installed the delrin buttons was to allow three of them to go through the compression tube, sitting on a shoulder to keep the tube from rubbing the receiver, and to extend through the comp. tube to center the rear of the piston.  The front of the piston was also buttoned and centered.  Anyway, everything seemed fine if the compression tube was out of the receiver, but when it was inserted, it was pinching the piston and making it difficult for it to slide. 

By sanding down the buttons, I was able to get the piston free until only the seal is providing friction, now.  This brought the numbers up somewhat, but they are still low, IMO.  I compared them to the #'s on the straight shooters website in the "our take" tab for the 97 rifle.

I added a spacer to the front of the spring, again raising the numbers slightly more.  Still only about 12 FPE.  The spring guide is not very tight, and can be pulled out without twisting it.  I used moly on the seal and Mccarri Heavy tar on the spring.  It is not twangy at all.

The numbers now are:   JSB 10.34 @ 725fps,    JSB 7.87 @ 846fps,   Super dome @ 801fps,   JSB 8.4 @ 815fps.  Accuracy is good.

This still seems less than the advertised numbers for the 97.  What do you all think?  I still have the original guide and top hat, but don't want the twang back.

Today, I just ordered the SHO Vortek kit.  I have never used a "purchased kit" before, only doing polish and lube tunes along with new guides.  I am hoping this will improve the numbers.  I am wanting to reach 13-14 FPE. 

Any suggestions for lube, etc, to use with the Vortek kit when it arrives?  Did I shoot myself in the foot with my home tune?

[Supaflee]

Tomcat , maybe it's a rifle set up for the English specification of 12 ft/lbs ? I dunno what mine is , I dont care , its rediculously accurate though . Mine is .22 cal . so smooth and quiet I hardly know its gone off .
 Regards Supaflee

[Tomcat]

Tomcat , maybe it's a rifle set up for the English specification of 12 ft/lbs ? I dunno what mine is , I dont care , its rediculously accurate though . Mine is .22 cal . so smooth and quiet I hardly know its gone off .
 Regards Supaflee

I thought about that, but when I counted the coils on the spring, it was 31 coils of .120 wire.  I think I read where the 12fpe version was 27 coils.  Thanks for your comment.  Good idea, but I think I have what is supposed to be the higher power version.  I bought it from a vendor in the states.  I have to go and find my initial chrony results, (if indeed I still have them).

PS:  I just found a target with the velocity listed for RWS super domes, and it matches exactly at 815fps.  Unfortunately, I don't know if I had buttoned the piston or not at that time.  Anyway, it is the same now, although still low, IMO.

[RinCG]

Tom,
 your #'s seem to match what mine were when I received mine several years ago. It shot very well despite what I felt were low numbers.
Am not the least bit disappointed in mine.
Hornet kit with a Ultra XLD (iirc) spring, lightly sized Hornet seal & similar piston button set up.
It's brutally accurate and by most others opinions, slow. Running about 11 ft lb- I Love it!
If squirrels have eye lashes, I haven't noticed as I believe I shoot them off.
Most of the "late" 97's do have issues with compression tubes, compression chambers and piston run out.
 Without correction, will be on slow side or hard on wear parts.
   

[grauhanen]

Most of the "late" 97's do have issues with compression tubes, compression chambers and piston run out.
 Without correction, will be on slow side or hard on wear parts.

Can you tell us more about these issues?  HW97 shooters -- are you familiar with these problems, too?

[Tomcat]

Tom,
 your #'s seem to match what mine were when I received mine several years ago. It shot very well despite what I felt were low numbers.

Most of the "late" 97's do have issues with compression tubes, compression chambers and piston run out.
 Without correction, will be on slow side or hard on wear parts. 

Glad to know your #'s were similar, but I still feel it is low.  I had not heard about the compression tube issues with the 97s.  If you have any more details, I would be interested, also.

Thanks for your comment.

[Tomcat]

Most of the "late" 97's do have issues with compression tubes, compression chambers and piston run out.
 Without correction, will be on slow side or hard on wear parts.

Can you tell us more about these issues?  HW97 shooters -- are you familiar with these problems, too?

+1    Any more comments would be appreciated.

[Tomcat]

Well, I went to tinkering again this morning.  I put the original metal tophat back in along with two delrin spacers.  Got it shooting S. Domes @ 825fps now.  The shot cycle is still good.  I decided to leave it alone at this point.  I e-mailed Vortek, and since my order for the tune kit had not yet shipped, they graciously allowed me to cancel.  I may be missing a great improvement, but since I have never experienced a Vortek drop in tune, I am happy with what I have at the moment.  That could all change again .  Still open for any thoughts or ideas.

Thanks

Tom

[Motorhead]

Well, I went to tinkering again this morning.  I put the original metal tophat back in along with two delrin spacers.  Got it shooting S. Domes @ 825fps now.  The shot cycle is still good.  I decided to leave it alone at this point.  I e-mailed Vortek, and since my order for the tune kit had not yet shipped, they graciously allowed me to cancel.  I may be missing a great improvement, but since I have never experienced a Vortek drop in tune, I am happy with what I have at the moment.  That could all change again .  Still open for any thoughts or ideas.

Thanks

Tom

Tom,
Personally getting to tune a lot of HW's ... Find the factory piston seal more times than not is marginal in having a good fit to compression bore ( Sizing down a slightly oversize Maccari or Vortek ) has given better results than using the OEM seal.

Another more recent practice is complete elimination of Moly lubes and spring tars.
Instead I prep action by thoroughly degreasing with Naptha and lube entire action with ULTIMOX 226 / Krytox synthetic lubes.  This free's up the action even more 

[Booger]

My HW97K is still in the break in stage after tuned. She was not shot much after she was tuned and then sold to me. Here is what I was getting 2 months ago:

LO   845.80   13.35
HI   870.20   14.13
AVG   862.03   13.86
EP   24.40   
SD   5.61   

I will check her out again in a few weeks, I expect the EP & SD to be a bit better,

[bReTt]

Hey Tom! 

My 77 (same action) shot 885 with 8.3 gr pellets when new.  I did a home tune job on mine and I cut the stock spring to bring the velocity down to 850 (13.5 fpe).  I read that you cancelled your Vortek kit order but you were asking about the lubes.  Vortek packages the lube that they suggest with the kit should you ever decide to get one at a later date.  They give you enough lube for 2-3 relubes in the included container.  Maybe you could try a new piston seal in it and see how that does?  Just thinking.  When my R9 was having extreme velocity spreads, I changed everything else BUT the piston seal and it still had issues even though the #'s were improving.  When I changed the seal, problem solved!   

How were the chrony #s as far as consistancy?  Have you tried a new breech seal?  Just asking because these are some of the issues that I have read about being "common" in the 77/97s.  I leave my cocking arm unlatched when stored to help keep the pressure off of the breech seal.  In my mind, it would have less chance to get crushed and lose the seal.  It could just be mental too!  ha ha. 

Have fun with it.  Tinkering is half the fun.

Brett

[Tomcat]

Well, I went to tinkering again this morning.  I put the original metal tophat back in along with two delrin spacers.  Got it shooting S. Domes @ 825fps now.  The shot cycle is still good.  I decided to leave it alone at this point.  I e-mailed Vortek, and since my order for the tune kit had not yet shipped, they graciously allowed me to cancel.  I may be missing a great improvement, but since I have never experienced a Vortek drop in tune, I am happy with what I have at the moment.  That could all change again .  Still open for any thoughts or ideas.

Thanks

Tom

Tom,
Personally getting to tune a lot of HW's ... Find the factory piston seal more times than not is marginal in having a good fit to compression bore ( Sizing down a slightly oversize Maccari or Vortek ) has given better results than using the OEM seal.

Another more recent practice is complete elimination of Moly lubes and spring tars.
Instead I prep action by thoroughly degreasing with Naptha and lube entire action with ULTIMOX 226 / Krytox synthetic lubes.  This free's up the action even more 

Hi Scott,

Can you give any more information about the amount and location where you use the Ultimox 226 without giving away your secrets?   I can still get the Vortek kit if you would think that is the best option.  I have tried to call Vortek, but get no answer.  I sent another e-mail and asked them to just sit on the order and not cancel it until I can decide what to do.  Do you think the SHO kit is what I should get?

My 97 is with the 26mm diameter piston and tube.  My rifle has never performed to the level that Brett and others are/were getting.  I am sure the buttons are not causing any drag now, but maybe the moly lube and spring tar are causing some loss.

The older I get, the more problem I have making decisions. 

Thanks for your help.

Tom

[Tomcat]

Hi Booger,  is that the S. Dome pellet giving you those numbers?

Brett, I have never reached the numbers you have with your 97 and you have shortened your spring.  I must have gotten a weak one .  I have done the tissue test over the breech seal, and see no leaks there.  825 fps is the best I have been able to reach with S.Domes and H&N Ftt.  Accuracy does not seem to be suffering though.

I haven't checked 10 shot spreads since I put the metal TH and two spacers back in, but 5 shots was around 820-825. Oh, BTW, I leave my lever unlatched also, and with a piece of cork under it to just barely release pressure from the spring.  Wine corks work best .

What do you all think?  Do I need a kit or relube with Ultimox and forget it?

[Booger]

JSB 8.4 domed pellets for my HW97K at this time. It seems my rifles like either JSB 8.4 pellets or H&N FTT 4.51 heads best.

[Motorhead]

Well, I went to tinkering again this morning.  I put the original metal tophat back in along with two delrin spacers.  Got it shooting S. Domes @ 825fps now.  The shot cycle is still good.  I decided to leave it alone at this point.  I e-mailed Vortek, and since my order for the tune kit had not yet shipped, they graciously allowed me to cancel.  I may be missing a great improvement, but since I have never experienced a Vortek drop in tune, I am happy with what I have at the moment.  That could all change again .  Still open for any thoughts or ideas.

Thanks

Tom

Tom,
Personally getting to tune a lot of HW's ... Find the factory piston seal more times than not is marginal in having a good fit to compression bore ( Sizing down a slightly oversize Maccari or Vortek ) has given better results than using the OEM seal.

Another more recent practice is complete elimination of Moly lubes and spring tars.
Instead I prep action by thoroughly degreasing with Naptha and lube entire action with ULTIMOX 226 / Krytox synthetic lubes.  This free's up the action even more 

Hi Scott,

Can you give any more information about the amount and location where you use the Ultimox 226 without giving away your secrets?   I can still get the Vortek kit if you would think that is the best option.  I have tried to call Vortek, but get no answer.  I sent another e-mail and asked them to just sit on the order and not cancel it until I can decide what to do.  Do you think the SHO kit is what I should get?

My 97 is with the 26mm diameter piston and tube.  My rifle has never performed to the level that Brett and others are/were getting.  I am sure the buttons are not causing any drag now, but maybe the moly lube and spring tar are causing some loss.

The older I get, the more problem I have making decisions. 

Thanks for your help.

Tom

Piston chamber walls & behind seal get a light coat of 226.  Spring and guide get heavier coat of 226.  Linkages, rear end of tube where piston tail slides is thinned mix of 226 and Krytox. Linkages & trigger mechanics Krytox 

Correct de-burring / polishing with surface prep key in using these lubricants.

[Tomcat]

Thank you Scott.  I very much appreciate the help. I will try and get some of the ultimox.

Also, thank you Booger for the numbers.  I will check mine again tomorrow with the JSB's.  I had 815fps but that was with delrin tophat.  I now have the original metal tophat with 2 delrin spacers, about 3/8" total.

[bReTt]

What do you all think?  Do I need a kit or relube with Ultimox and forget it?

Well Tom, IF it were MY gun and I was sure that I had done everything else inside the rifle correctly, I would at this point, order a new spring, guide and seal.  OR if I could have easy access to just a new piston seal, I would do that first, along with replacing the breech seal.  That would be the only thing I would know to do personally. 

Before I did that, I would probably take the rifle apart one more time and go over everything again and maybe test the fit of the piston seal for being too tight or loose and give it a good cleaning and inspection.  I would take 1500 grit sandpaper and go along the edges of the seal with it assuming it's a good fit and seal inside the compression tube.  Test the seal by pushing the piston and seal all the way in the compression chamber and then using your finger, seal the transfer port/breech port and pull back on the piston rod like you are trying to remove it.  It should be hard to pull back and should pop back forward if it's sealing well.  Same thing other way too.  Pull it back and seal the port and push the piston forward.  Should be hard and want to spring back on you.  That's a simple test and if it passes that test it doesn't mean that the seal is always good, it could still not be sealing well under firing/compression conditions.  If it fails those tests, it's a bad seal.

Do you have another spring that you could use in the 97?  A spare or one you can swap with a compatible gun?  That's always an option IF you have one. 

I don't know for sure but, I wouldn't think that just cleaning and relubing with a different lube would solve the problem.  It may help BUT I will bet most of those #'s that others are getting with their rifles are with traditional lubes (moly, spring tar, clear tar....) so that leaves me to think it's another issue that need to be solved.  Nothing wrong with switching lubes but that's not the only issue. 

I know, lots of writing just to say that if you can swing the expense of ordering a new spring/guide and seals... do it.  If those don't work then you know for sure it's something else.  Something bigger than I have ever had to deal with.  In that case it may be worth the time and expense to send it to a professional with a medical history on the rifle!  I don't think that it will come to that but there is always that possibility. 

[Tomcat]

What do you all think?  Do I need a kit or relube with Ultimox and forget it?

Well Tom, IF it were MY gun and I was sure that I had done everything else inside the rifle correctly, I would at this point, order a new spring, guide and seal.  OR if I could have easy access to just a new piston seal, I would do that first, along with replacing the breech seal.  That would be the only thing I would know to do personally. 

Before I did that, I would probably take the rifle apart one more time and go over everything again and maybe test the fit of the piston seal for being too tight or loose and give it a good cleaning and inspection.  I would take 1500 grit sandpaper and go along the edges of the seal with it assuming it's a good fit and seal inside the compression tube.  Test the seal by pushing the piston and seal all the way in the compression chamber and then using your finger, seal the transfer port/breech port and pull back on the piston rod like you are trying to remove it.  It should be hard to pull back and should pop back forward if it's sealing well.  Same thing other way too.  Pull it back and seal the port and push the piston forward.  Should be hard and want to spring back on you.  That's a simple test and if it passes that test it doesn't mean that the seal is always good, it could still not be sealing well under firing/compression conditions.  If it fails those tests, it's a bad seal.

Do you have another spring that you could use in the 97?  A spare or one you can swap with a compatible gun?  That's always an option IF you have one. 

I don't know for sure but, I wouldn't think that just cleaning and relubing with a different lube would solve the problem.  It may help BUT I will bet most of those #'s that others are getting with their rifles are with traditional lubes (moly, spring tar, clear tar....) so that leaves me to think it's another issue that need to be solved.  Nothing wrong with switching lubes but that's not the only issue. 

I know, lots of writing just to say that if you can swing the expense of ordering a new spring/guide and seals... do it.  If those don't work then you know for sure it's something else.  Something bigger than I have ever had to deal with.  In that case it may be worth the time and expense to send it to a professional with a medical history on the rifle!  I don't think that it will come to that but there is always that possibility.

Thanks Brett.  Sounds like a reasonable plan.  Unfortunately, I do not have either another spring or another seal to try.  If I can get in touch with Vortek tomorrow, I will go ahead and get their kit.  I suppose the PG2 SHO kit is what I want for full power.  Looks like it is either the sho or the 12fpe kit as the options on their site.  I already have 12 fpe .  I have ordered some of the Ultimox lube Scott suggested.  I am anxious to try it.  I don't know what kind of lube comes with the kit.

[T-Higgs]

Tom,
You will really enjoy the SHO kit.  My 97 has one and it is smooth, quiet and twang free. I'm excited for you since this is your first Vortek tuned gun. If you are going to use Ultimox, you can request Vortek to not pre-lube the kit. I'm not sure what Tom at Vortek uses for lube but Ultimox should not be mixed with other petroleum based lubes. Please inform us post kit thoughts. My 97 is older 25mm tube and is shooting 16.5 FPE.
Regards
Tim

[Tomcat]

Tom,
You will really enjoy the SHO kit.  My 97 has one and it is smooth, quiet and twang free. I'm excited for you since this is your first Vortek tuned gun. If you are going to use Ultimox, you can request Vortek to not pre-lube the kit. I'm not sure what Tom at Vortek uses for lube but Ultimox should not be mixed with other petroleum based lubes. Please inform us post kit thoughts. My 97 is older 25mm tube and is shooting 16.5 FPE.
Regards
Tim

Thanks Tim.  You are getting a good amount of power out of your rifle.  I hope to talk with someone from Vortek tomorrow.  Thanks to you I learned something new, as I didn't know the kits came prelubed.  Thanks for the heads up.

I just came up from the basement after a late shooting session.  My JSB 8.4 gr are shooting @ 833 avg, ES 18fps. for 12.95 ftlbs.  H&N 8.64 @ 816 avg, ES 13 fps for 12.78 ftlbs, and finally, RWS S. Dome @ 824 avg,  ES 8 fps for 12.5 ftlbs.  10 shot averages for JSB and H&N.  9 shot average for SDomes (oops!)

Still not up to par, but the best numbers so far.  This is with stock spring and seal, steel tophat and approx 3/8" spacer in front of tophat, moly lube and heavy tar on the spring.

Update Friday am:  Back on track with the Vortek SHO kit.  It will ship today.  Looking forward to trying it.