Tuning Stock FX Impact M3 .22 600mm balls-to-the-wall tune for heavy slugs?

[Der_Berend]

Not talking about accuracy or even basic common sense practicality here, I strictly want to see the biggest number I can (energy-wise) on the chrony because big numbers are a lot of fun.

How do I "tune" to get the absolute maximum muzzle energy out of my very stock .22 M3? The max I've managed so far was 62 fpe pushing JSB knockouts around 320 m/s but 145 bar seems to be about the maximum reg pressure the stock hammer can still push open. I tried to go higher yesterday but I ended up around 53 fpe with 36 grain ZAN slugs. Has anyone managed higher with this particular setup?

 

[athlon_oved]

Do you have the 800mm barrel and power block on your m3 yet?

 

[Der_Berend]

Do you have the 800mm barrel and power block on your m3 yet?

It does have a power block, but no slug power kit and a 600mm barrel.

 

[Heavyopp]

I have the same gun and found the same thing as you. Can’t open the valve after 145-150 bar on the reg.

I‘m able to get 25.4 grn fx pellets to 1011 fps. Wanna see what happens to the grouping at higher speed At 100 yards. Right now best I can get at any speed at 100 yards is a dollar bill sized groups with those pellets.

 

[TheCarFather]

I don't have an Impact, only a Maverick, but swapping in a heavier hammer weight makes a BIG difference on potential power output. It's also an inexpensive part and fairly simple to install. If you are looking for maximum power that's where I would start. You are maxed out right now with the stock hammer weight.

 

[Der_Berend]

I have the same gun and found the same thing as you. Can’t open the valve after 145-150 bar on the reg.

I‘m able to get 25.4 grn fx pellets to 1011 fps. Wanna see what happens to the grouping at higher speed At 100 yards. Right now best I can get at any speed at 100 yards is a dollar bill sized groups with those pellets.

I'm guessing 1011 fps is well past the critical Mach number of those pellets, or any pellet, for that matter. You'd probably have to push them well beyond the sound barrier to get them to stabilise again but that's pure conjecture on my part. Have you tried slugs?

 

[Der_Berend]

I don't have an Impact, only a Maverick, but swapping in a heavier hammer weight makes a BIG difference on potential power output. It's also an inexpensive part and fairly simple to install. If you are looking for maximum power that's where I would start. You are maxed out right now with the stock hammer weight.

Thanks for the feedback, I was guessing as much but good to see that that's indeed what is going on. Might order the slug power kit then and get some more adjustability.

 

[Heavyopp]

I'm guessing 1011 fps is well past the critical Mach number of those pellets, or any pellet, for that matter. You'd probably have to push them well beyond the sound barrier to get them to stabilise again but that's pure conjecture on my part. Have you tried slugs?

I haven’t shot these pellets at this speed yet other than over the chrony, just turned the gun up to make it happen

I don’t expect much in a accuracy department but in another thread someone had suggested 1050fps as a sweet spot for the impact and these pellets. As I said, I’m skeptical but I’ll try them.

I have briefly tried slugs, decent results, may go down that road but they sure are expensive.

 

[kendive]

Do you have the 800mm barrel and power block on your m3 yet?

Wait what they have an 800mm barrel kit now?

 

[athlon_oved]

Yup. 800mm, power block and tungsten weight. If you are looking for the most fps you need that.

 

[athlon_oved]

Me though... happy with my 500mm 25 cal 300 bar 185 shot m3 shooting 900 to 940 fps using pellets and some Nielson slugs.