Tuning Impact M3 slug Power kit tune

[Powerage]

Hello 



I just picked up a M3 in 22 with a 600 mm superior standard barrel. My goal is to shoot the javelin 26 grain or 30 grain at 1000 FPS. I installed the slug power kit. Should I use the Matt Dubber tune with high reg 160 + for the slug power kit with the M3 ? With the weak return spring the gun uses the plenum pressure to close the valve . A short burst of air is what we want ? Or am I wrong ? 

 

[biohazardman]

You have it correctly thought out. High reg pressure is the most efficient way to shoot.

 

[Powerage]

Thank you for the reply. Can’t seem to find other with similar setups . Some YouTubers run the slug p kit setup at lower reg so I got confused. Guess I try the Matt dubber tune first. That works brilliant with my mk2 

 

[ram2jeep]

You would need to tune your M3 for the 30gr and then back down the macro and valve to get your desired fps for the 26gr. I believe Matt's rifle through Utah is MK2 so his regulator pressure may be a tad higher than actually needed for the M3. 
Regardless your going to have to tune the rifle after adding the power kit so I would start tuning with the valve adjuster out and then gradually increase reg pressures until your over your desired fps then adjust using the macro with the valve adjuster after that. 
Look at AirBuks or Ernest Rowe's videos on tuning and you will see and then be able to hopefully find your rifles sweet spot. This is the fun and sometimes stressful part of the Impact; tuning for your desired pellet/slug. 

 

[Powerage]

Thank you for your reply. Your method is the one I always used until Matt posted his tuning video with the MK2. The M3 is like you said delivered with a bigger plenum so things might be different. I’m not sure if the M3 got 52 or the 56 mm hs and the hammer weight from factory ? The slug power kit comes with a very weak return spring causing the valve to open more that’s why I thought high pressure is needed to don’t waist air. 


guess I will try both methods 

 

[M0ist0ne]

The weak return spring won't work right with the M3. 

The only thing you can really use are the hammer weights and pin probe. 

 

[jerrymail]

The weak return spring won't work right with the M3. 

The only thing you can really use are the hammer weights and pin probe.

Yes, Ernest also said only put on the pin probe because M3 has a different design.

 

[Powerage]

That was new to me. You have a link to Ernest video? Thank you 

 

[jerrymail]

I sent email to him asking the slug kit questions. My M3 is .25 compact.

 

[Powerage]

That’s good. Keep us updated. I did some testing yesterday with the weak returnspring and I gained a lot FPS with my 600 mm barrel. things never became very harmonic. So I reinstalled the original returnspring and after some tuning I was able to find a sweet spot for my h n 25 grain slug at 950 FPS. Reg 1 175 reg 2 125 macro adjuster 16 and micro 4.5. Valve knob 4.5 lines. It’s slug on slugs at 60 meters . Will test at longer distance today . 

 

[jerrymail]

That’s good. Keep us updated. I did some testing yesterday with the weak returnspring and I gained a lot FPS with my 600 mm barrel. things never became very harmonic. So I reinstalled the original returnspring and after some tuning I was able to find a sweet spot for my h n 25 grain slug at 950 FPS. Reg 1 175 reg 2 125 macro adjuster 16 and micro 4.5. Valve knob 4.5 lines. It’s slug on slugs at 60 meters . Will test at longer distance today .

How about your M3 1st reg at 175 bar? I increased my 1st reg 175bar, 2nd Reg 145bar. Shooting 988~1018fps with power wheel and Micro adjuster all max out, valve over 4th line. But the 1st reg doesn't work property. The pressure just recover slow after every shoot. I will try to add more 1st reg washers and change stacking. If it not work, I will try to lower reg until get a more consistent velocity.

 

[Powerage]

I dont know how much the first reg matters as long it’s about 30 over the other one I think you are good. I tested my tune also with the nsa 24.8 and it’s promising. Tested out to 135 meter with nice groups in slight breeze. Was hoping to run some heavier slugs . I have 8000 javelins in 30 grains 218 in my locker .