Tuning Impact power tuning spring vs spacers

[caesar]

Use my Impact for shooting 38gr NSAs usually. So I have just about all the power mods installed. It shoots great but the spacers that come with the slug power kit make the gun feel a bit over powered. Can hear the hammer smacking that valve. 


Took both hammer spacers out and put in the Huma tuning spring I already had. Figuring I’d get less but about the same power out of it and it would go back to sounding a bit smoother. The Huma spring itself is about as long as the FX spring + the spacers. So I backed off the hammer just about .2mm (18.99mm where is set)


i was right about the sound and feel. But was shocked that I’m actually getting more power out of it. About 20fps more on 3 than I was getting on 5 before the swap. No regulator adjustment but now I feel like I have some headroom too. With the spacers installed it felt maxed out and over powering the valve. 

I know I know. Very long story for just a small bit of info. but I’m much happier with the Huma spring vs the factory spring and spacers. Maybe I WILL try out some of those 49gr Altaros slugs hmm…

 

[M0ist0ne]

I run only one of the spacers in the kit on mine. As I agree, two spacers is too much. 

 

[SkaDaddy]

Caesar, I am looking at deciding between the Huma and FX slug kit as well. 
What are you using ( or would recommend) for the valve return spring ( factory, Huma or slug kit version)? 


cheers 

 

[bigHUN]

I have power upgraded my Impact, including machining the transfer ports and larger valve poppet as well. I don't use the famous kit you guys mentioning, and no pin but the Huma gen.2 probe with a large brass transfer port whichever generation or version it is. I have tried so many hammer + valve spring combinations (with a larger hammer weight) I don't remember anymore which is the original anymore, for sure I have 5-6 of each all mixed up in the box now.

But the springs I was playing with the most and currently in the gun, the most power gives the original first gen Impact hammer spring (way stronger then the power plenum version spring) with a latest generation Huma valve spring. And again I am talking about pellet probe not a pin...I trust the pin will not give more power then the probe, also can create problem with slugs placement.

Also I have to mention what I learned. You can tune in million ways, but the most common language are the two, long dwell time and short dwell time.

I prefer the short dwell time, higher Reg and heavier hammer kick, and turns out this is also a most shot count as well. And btw I am tethering anyway.

 

[california.airgun]

Im curious, i am using everything that came with the kit, besides the rubber ball for the valve adjuster, is there anything that i shouldnt have used? Ive seen others not use both hammer weights or springs? Just getting some confirmation. 

 

[bigHUN]

If you set the Reg higher you shall use the heavier weight to override the valve and may need a heavier hammer spring as well. All depend how you want to use the Reg

 

[corny]

The spacers add a total of 3mm preload to the HS plus the weight.

I found it made the gun very violent…didn’t prefer it.