Anyone Have Favorite Settings for .177 FX Impact MKII ?

[grandspud]

I recently acquired an FX Impact MKII Compact in .22 caliber. This setup is a good, all around caliber for within the confines of my somewhat generous, suburban property.

I always knew I would buy two additional caliber change kits. The .25 for when I stay on daughter's Idaho ranch and .177 for when I want to be extremely stealthy (silent discharge, lower target impact noise, reduced projectile travel) while plinking and dispatching mice and other pests in my semi-rural/ suburban, So. Cal. home.

My question is do any of you shoot a .177 Impact MKII... and if so what are your favorite parameters?

• Pellet choice?
• Regulator setting?
• Hammer spring setting?
• Valve stop setting?
• Approximate fps?
• Accuracy results?

Thanks! My hope is someone will have a favorite that I can use as my starting point when shifting over to .177.

 

[tor47]

I use jsb heavies shoiting around 890- 920 fps. Hard to tell what regpressure but if you aim for a max speed around 920-950 (where the gun can not shoot faster), and adjust down from there, you will probably find an accurate speed at around 900.

 

[tor47]

You probably has to use slack on hammer spring wheel on the lowest setting. By that I mean "min" have no pressure on spring.

 

[tor47]

You can not "copy" settings from other owners. The gauges are not accurate enough to know exact what your regpressure is, or what theire is. You basically has to try your own settings.

You also do not necessary have to change the regpressure on the gun when you switch barrel, as using hammer wheel, and valve adjuster still can give nice ES when shooting .177. But if you do not plan to swap calibers back and forth, it is probably a good idea to start testing with lower regpressure, than your .22 setting.

 

[bucketboy]

Leave your reg alone, .177 require higher pressure to overcome the extra friction of the air squeezing through the smaller transfer port and pellet being pushed up the barrel, so although the pellet is lighter and will have less energy than the .22 it will require similar settings.

You don’t need heavy pellets at 950fps to dispatch mice , plink or shoot paper, I recommend 8.4grain jsb @ 800fps, still more than enough power for small game including squirrels and rabbits. Accuracy will be at a maximum, noise and air consumption at a minimum.



Bb

 

[Spierings]

Sub 12 .177 impacts have a very low reg pressure (around 50bar) 



I have a full powered impact with .177 barrel and tuned it down to that power level, reg is around 50, no hammer spring tension and the valve stop around second line. Het a great shot count, probably around 450.



Other way is to do the rubber ball trick, see the Ernest rowe video about it, i did not have the rubber ball. Probably going to order one so i don't need to tune it so far down.

 

[tor47]

Think aprox 80 bar is the minimum air pressure available on mk2, before reg piston bottoms out. If you adjust, make sure you do not force it . Best way is to degass the plenum, and adjust genttly until you feei a litle resistance, and lossen up again some, so the pistion has room to move.

 

[sniperlabyo]

I recently acquired an FX Impact MKII Compact in .22 caliber. This setup is a good, all around caliber for within the confines of my somewhat generous, suburban property.

I always knew I would buy two additional caliber change kits. The .25 for when I stay on daughter's Idaho ranch and .177 for when I want to be extremely stealthy (silent discharge, lower target impact noise, reduced projectile travel) while plinking and dispatching mice and other pests in my semi-rural/ suburban, So. Cal. home.

My question is do any of you shoot a .177 Impact MKII... and if so what are your favorite parameters?

• Pellet choice?
• Regulator setting?
• Hammer spring setting?
• Valve stop setting?
• Approximate fps?
• Accuracy results?

Thanks! My hope is someone will have a favorite that I can use as my starting point when shifting over to .177.

Mine Detuned To .177: 

ammo 10.5 CP

speed 750fps

reg 110

hammer spring length 50mm

no hammer weight just delrin spring guide 

STX pellet liner 500mm 

-1/2” at 50y

shot count 70



Ernest

 

[Guest]

on my impact mk2 PP .hammer tension at 20mm. reg pressure 90 front valve at line 2.5. with jsb 10.34 i was getting 944fps on max power wheel and 860fps on 3 minimum was on 790

 

[bucketboy]

I recently acquired an FX Impact MKII Compact in .22 caliber. This setup is a good, all around caliber for within the confines of my somewhat generous, suburban property.

I always knew I would buy two additional caliber change kits. The .25 for when I stay on daughter's Idaho ranch and .177 for when I want to be extremely stealthy (silent discharge, lower target impact noise, reduced projectile travel) while plinking and dispatching mice and other pests in my semi-rural/ suburban, So. Cal. home.

My question is do any of you shoot a .177 Impact MKII... and if so what are your favorite parameters?

• Pellet choice?
• Regulator setting?
• Hammer spring setting?
• Valve stop setting?
• Approximate fps?
• Accuracy results?

Thanks! My hope is someone will have a favorite that I can use as my starting point when shifting over to .177.

Mine Detuned To .177: 

ammo 10.5 CP

speed 750fps

reg 110

hammer spring length 50mm

no hammer weight just delrin spring guide 

STX pellet liner 500mm 

-1/2” at 50y

shot count 70



Ernest

Shot count 70? This doesn’t seem right, my impact (admittedly 480cc) would do 500+ with jsb heavies

Bb

 

[sniperlabyo]

Same here if set up at 13fpe with 480cc. This has a 200cc didn’t really test total shot count. This one i only fill to 150b and shoot 2 mags 76 shots and refill to 150b this is her sweet spot fill. i keep this impact stress free, lots of parts been modified for 12-13fpe for my back yard snipping and 10meter comp. 

Ernest 

 

[Odoyle]

Ernest knows to keep the max fill pressure lower than 200bar for best results to keep everything on his Impact stress free too.

 

[grandspud]

Ernest, I'm new to regulated PCP guns and learning. One reason I got rid of my unregulated Discovery and MarauderP was because I didn't want to deal with the "sweet spot" fills anymore.

Do regulated guns actually have a "sweet spot" fill? I thought the whole idea behind a regulator was to get rid of that. The gun should only be seeing the air after it has been regulated... right?

Thanks.

 

[sniperlabyo]

Ernest, I'm new to regulated PCP guns and learning. One reason I got rid of my unregulated Discovery and MarauderP was because I didn't want to deal with the "sweet spot" fills anymore.

Do regulated guns actually have a "sweet spot" fill? I thought the whole idea behind a regulator was to get rid of that. The gun should only be seeing the air after it has been regulated... right?

Thanks.

if you have the reg set at 110b and filled to 250b it’s normal to have 18fps or lower ES. It you write down the whole shot string and reg pressure you will see what reg pressure that will have the lowest ES below 5fps