M3 vs M2 Valve Adjuster

[IanB]

I own an Impact Mk2 and also the Mk3.

Using the Mk2 the valve stop has much more adjustment before it affects velocity, I leave it on line 4 and sometimes do not see any velocity drop until I get to line 2.

Whilst the M3 I have to leave the valve stop out way past line 4, maybe like line 5 if there was a line 5 to get the best velocity , if I take it to line 4 velocity drops by 100fps, if I take it to line 3 or 2 the gun does't fire, the valve cannot open.

Is this normal for the M3, I also tried putting a slug power kit spring in, the lighter one and its basically the same... Seems pointless even having the markers on if they cannot be used due to not opening the valve at all on these....

 

[Cranky1]

I have noticed this on my m3, I also wish the knob had a detent.

 

[Vetmx]

I didn’t notice a big difference in the spring tension of my MKll’s vs my M3’s valve spring. But I did notice a big difference where the C1 was set on the MKll’s vs the M3’s from the factory. Both are what influence where you have to have the knob set. If the C1 on your gun was set at 6.25mm from the factory and you set it to 6.50 or 5.75mm when you reassemble. Your previous valve knob setting is now out the window because you changed the preload. The knob will still work just fine but it will either start working earlier or later.