HW30S/JM Kit Quandry

[Grover]

On the other hand,  all 4 of my Vorteked 30S's shot at 7.5 to 8fpe (675-705 fps with 7.33 JSBs in the case of .177) immediately after installation and have remained there through several thousand shots collectively.  That said, the shot cycle on a Vortec 30s does have a little more drama. Not harsh, just lively.

Not trashing JM.  Just sharing my honest experience. If a smidge more power is what you seek,  then vortek is worth consideration. 

[Oldgringo]

With more shooting, the velocity has kicked up to 600-610 fps.  The fixing screws are somewhere between Ohio and Texas.  Once they arrive, I'll take her down and put a nylon washer in front of the spring, replace the piston seal and see what happens.  I don't want to turn her into a cannon, I have a R9 for that.  OTOH, I don't want to screw up a sweet and accurate little 30 yard gun either.

[stija]

Increasing fpe will inevitably lead to a harsher cycle. Laws of physics, period. Having said that only you know what the trade off will be, accuracy or power. Just add spacers until desires speed is reached.

I had a thread comparing JM and Vortek 12lb offerings and there is no difference in harshness of shot cycle when shooting at same speeds. In fact, I kept the 12lb Vortek kit with one spacer shooting at 11.4fpe.  JM kit came with three plastic spacers for this purpose precisely.

[Grover]

With more shooting, the velocity has kicked up to 600-610 fps.  The fixing screws are somewhere between Ohio and Texas.  Once they arrive, I'll take her down and put a nylon washer in front of the spring, replace the piston seal and see what happens.  I don't want to turn her into a cannon, I have a R9 for that.  OTOH, I don't want to screw up a sweet and accurate little 30 yard gun either.

If it were me, but it's not, I would try it with a new seal without the spacer first. I'm betting you'll be right around 650 with that bad boy.

[SpiralGroove]

Hey HW30S enthusiasts',

After thinking about what has happened to my HW30S, I have the following hypothesis. 

The HW30S is simply easier to shoot accurately at velocities approaching 675 fps.  I found my gun became more (intuitively) accurate to shoot when making adjustments in distances from 10 yards to 50 yards.  I think the lower velocity alters the pellet trajectory enough to diminish the guns performance.  I know that my barrel didn't just become less accurate, it seemingly had to do with  lessening the optimal velocity for the power plant (using 7.33 gr. Falcons).

That's all I got; has anyone else experienced this or is my theory just nonsense?
   

[Oldgringo]

Well, I installed the new JM seal today and tried two different thicknesses of nylon washers.  The rifle would not cock with either washer.  So, I put her back together for the third time and shot her over the chrony using AA 7.33 gr. Falcons.  It appears the velocity is now up to a little over 600 fps.  She is quiet and smooooth as butter with a solid thunk and as accurate as ever.  I'm through fooling with this one FTTB, maybe she'll speed up a little over time?

I got out my other HW30S who has been neglected of late.  She still shoots AA 7.33 gr. Falcons quite accurately in the 650-660 fps range but BOY HOWDY, is there ever a twangy difference in the noise level and shot cycle.  I think that I'll go ahead and drop the other JM kit into Miss Peeper.  My backyard range is limited to 30 yards and I'm much more interested in accuracy than I am in FPE or velocity.  As long as I can hit my spinner spoons and shotgun shells with these two girls and their open sights, I be cool.   

Now then it's almost GO VOLS time.  Y'all come see us.

[SpiralGroove]

Yeah Old Gringo,
Working on our toys can be a very frustrating game indeed .

When the gun wouldn't cock, were your spacers fitting inside the piston? 
If Yes, the fully compressed spring takes up all the room inside the piston requiring a thicker, wired spring to increase velocity .
If No, smaller diameter washers O fitting inside the piston and over the piston rod should allow further compression ...... solving the problem.

If you don't know, I will find out soon enough
__________________________________________________

Also, you don't want the washers to increase the Spring Guide to Top Hat length or else they'll touch when cocking and the piston can't move further towards the sear.  When I added a Top Hat to the OEM Spring Guide, they touched and their combined length exceeded the pistons length .  I needed to reduce the length of my Spring Guide about 3/4" and they both fit inside the piston (it cocked).   The spring itself could have been compressed further.  This is all you want - more spring compression.

I hope that helps,

Kirk