Anyone convert FX Impact MK2 .22 calibre to .25 calibre?

Didn’t do this specifically but I do have an m3 with 600mm barrel tuned beautifully for 33.95 .25 heavies. So one day I thought I would throw a .30 cal set up on it with same tune figuring it would be ok. Wrong didn’t like the tune with a .30 cal 44.75 gr at all. Basically doing it is super simple. You just swap barrels and the probe. However it may require completely retuning the gun. Why in reality the whole swap ability of the FX platform isn’t as easy and great as they would have one believe.
 
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It is no problem as said.
Mind you you also need to replace the " nuts " in the ends of the barrel, CUZ the barrel itself are held in place by those inside the barrel pipe.
But of course if you get a complete replacement kit with a whole barrel assembly ready to drop in, well then sure you just do that, and then replace the pellet probe as said above.

I swapped my Maverick from a 600 mm barrel to a 700 mm one, but in same caliber, so here i just needed a longer barrel pipe ( too expensive )
¨So i got a 100 mm extension and then instead of getting a also longer shroud ( also too expensive ) i made my own shroud out of 3 carbon fiber pipes each sliding neatly into each other and then finally onto the barrel pipe ( light press fit )

IMO the price for upgrading the FX barrel system i find all together too expensive really, but it is probably the same with other upgradeable air rifles.

You of course also have to retune your gun changing caliber like that, just like if you would change to a heavier or lighter ammo.
 
I am almost ready going in opposite, to convert from .25x700 to .22x600.
I just want to minimize my .25 stock of JSB 34gn first, whit this my current paste in about a month I will do a conversion.
The .25 cal JSB MK1/MK2 is a good all around size, but I am shooting 100 M rings only with my Impact , the .22 slugs or the .30 pellets outperforms what I am currently using.
 
Didn’t do this specifically but I do have an m3 with 600mm barrel tuned beautifully for 33.95 .25 heavies. So one day I thought I would throw a .30 cal set up on it with same tune figuring it would be ok. Wrong didn’t like the tune with a .30 cal 44.75 gr at all. Basically doing it is super simple. You just swap barrels and the probe. However it may require completely retuning the gun. Why in reality the whole swap ability of the FX platform isn’t as easy and great as they would have one believe.
Thank you for your reply.

Yes, I reckon the whole of process of time consuming tuning would be required with a new barrel swap. I too have spent a lot of time fine tuning my MK2 to shoot the H&N 25gr gen2 slugs well. I was thinking about having a bigger calibre gun so my coyote hunts and this might be the cheaper way instead of buying a new gun. Not cheap to buy the barrel, probe & magazine either.

I guess I should have tried the .25 caliber M60B when Wes asked me if I want to review that gun. I am I was one of many who got sucked in by FX's advertising of calibre swapping.
 
It is no problem as said.
Mind you you also need to replace the " nuts " in the ends of the barrel, CUZ the barrel itself are held in place by those inside the barrel pipe.
But of course if you get a complete replacement kit with a whole barrel assembly ready to drop in, well then sure you just do that, and then replace the pellet probe as said above.

I swapped my Maverick from a 600 mm barrel to a 700 mm one, but in same caliber, so here i just needed a longer barrel pipe ( too expensive )
¨So i got a 100 mm extension and then instead of getting a also longer shroud ( also too expensive ) i made my own shroud out of 3 carbon fiber pipes each sliding neatly into each other and then finally onto the barrel pipe ( light press fit )

IMO the price for upgrading the FX barrel system i find all together too expensive really, but it is probably the same with other upgradeable air rifles.

You of course also have to retune your gun changing caliber like that, just like if you would change to a heavier or lighter ammo.
I though I could just buy a .25 calibre liner and swap out the .22. Then buy the probe and magazine. I remembered reading your 100mm extension mod. That was brilliant. Yes, everything is expensive when it comes to FX. It is a great platform, but pricey.

Thank you for your feedback.
 
I am almost ready going in opposite, to convert from .25x700 to .22x600.
I just want to minimize my .25 stock of JSB 34gn first, whit this my current paste in about a month I will do a conversion.
The .25 cal JSB MK1/MK2 is a good all around size, but I am shooting 100 M rings only with my Impact , the .22 slugs or the .30 pellets outperforms what I am currently using.
Yes, I agree with the ammo price of the .25 calibre. That was why I never purchased a 25cal PCP before. All my PCP are .22 except my Airarm S510 in .177. I already have lots of different brand and weight of .22 ammo from testings in the past.

It will be expensive either way if I venture down the .25 calibre route. I might have to just stick with my MK2 and tune it to shoot heavier slugs for my coyote hunt in the future.

Let me know how you get on with the switch after. Thank you.
 
In the past I have already collected a variety liners for Impact .25x700 and for my Leshiy2 conversions to .25.x600 also .22x600, so the expense was progressing gradually over years. In a Canadian airgun forum classifieds I offered some barrel kits but I understand that the budget is getting tighter with every mew day. So my calibre swap will be really just an elbow greasing.
My interest is only in 100 M rings shooting/scoring, after reading many posts from more experienced target competition guys I got to a decision to move on with .22 heaviest slugs.
 
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Yeah even if you stay with the same barrel length, there is a few other things you need aside for the barrel " straw " itself.
Most will remember to factor in the pellet probe, but the 2 barrel nuts that hold the barrel inside the pipe PPL tend to forget.
Also need a new brass part with the transfer port, as the one you have is tailored for ,22, so you would need a .25 of that too.

I have myself a carbon fiber pipe in a corner, i got for putting around my liner in the .177 maverick, but the problem is that CF pipe was procured by measurements of a .22 barrel.

So my .177 barrel just flop around inside that CF pipe as its 1 mm too big, but i have not checked if it would actually fit inside the barrel pipe too.
I would assume the barrel pipe work for more than 1 caliber though.

Huma have a sale and in it is 2 FX barrel kits for the impact, but it is just the .30 ( 500 mm ) and .35 versions ( 500 - 800 mm ), that probably do not sell much in EU ville.
Those are still 300 - 400 euro / Dollars kits, but then also complete and ready to drop right in.
 
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Yeah even if you stay with the same barrel length, there is a few other things you need aside for the barrel " straw " itself.
Most will remember to factor in the pellet probe, but the 2 barrel nuts that hold the barrel inside the pipe PPL tend to forget.
Also need a new brass part with the transfer port, as the one you have is tailored for ,22, so you would need a .25 of that too.

I have myself a carbon fiber pipe in a corner, i got for putting around my liner in the .177 maverick, but the problem is that CF pipe was procured by measurements of a .22 barrel.

So my .177 barrel just flop around inside that CF pipe as its 1 mm too big, but i have not checked if it would actually fit inside the barrel pipe too.
I would assume the barrel pipe work for more than 1 caliber though.

Huma have a sale and in it is 2 FX barrel kits for the impact, but it is just the .30 ( 500 mm ) and .35 versions ( 500 - 800 mm ), that probably do not sell much in EU ville.
Those are still 300 - 400 euro / Dollars kits, but then also complete and ready to drop right in.
Thank you for the suggestion. For the time being, I will try to shoot some heavier .22 slugs to see if I can get more power and accuracy. I am kinda reluctant to mess with my current setup with the 25gr slugs. I have great accuracy out to 100+ yards shooting starlings and doves at the moment.
 
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TBH i would prefer to buy another gun, and i just have, and sold another one.
If i went rouge and got a .22 barrel, i dont think what ever rifle i upgraded would ever go back to .177, so it would be like getting a new rifle.

No hurry though, the range grow to its max of 130 M this year, and .22 would only get really alluring to me going past that distance.
It is going to be damn hard to make .177 work at those distances as i / anyone cant really take full advantage of the heavy 20 grain stuff out there so no barrel handle it well.
 
Ya, I might have to do just that to buy another gun, lol. I will see how my future coyote hunt goes. My last two coyote shots had not gone well as I couldn't find the body after two head placement shots with the 25gr slugs.

It is extremely hard to shoot pass 100 yards even with .22 caliber let along .177 caliber. I don't intent to shoot any further distance, at least not with coyotes. So far starlings, doves and crows have been victims of my Impact MK2 and my M60B.
 
Max, if you’re going to have a coyote gun, make it a .30. My wicked M3 .25 slug shooter is shooting 1,048fps. My .30 RTI slugger shooting 900fps is more devastating. If your MKll is a dialed in .22 slugster, don’t mess with it. Enjoy it on critters that are in its wheelhouse. Do some research on .30’s. Like Crickets, Vulcans, Uragans and such. Then come up with a plan. There are plenty of uses for a .22 slugger and that caliber is generally more cooperative. What you’ll gain with a .25 might not be worth the hassle or investment for coyotes. They are a formidable adversary and .22 to .25 switch probably won’t be a game changer. A .30 is a game changer.
 
It seems for now that you have a place that always has coyotes. That place will always have them unless he poisons them. So if you think you are not in jeopardy of loosing that hunting spot, a coyote gun may not be a bad investment. Even a used Impact that is already a .30 might not be a bad idea if you can get it for a realistic price. You already know the gun.
 
I change my barrel length and caliber all the time. Too often. Surprisingly the tunes are close. You will find it easier to push the same weight 25 projectiles than the .22.

A less expensive way is just the liner, a huma changeover kit. https://huma-air.com/fx-impact-cali...nsfer-port-and-high-flow-pin-or-pellet-probe/ Carbonfiber sleeve and a printed magazine and your barrel. Make sure to pick you liner according to your application.

With the above configuration you don't have to buy a barrel kit then pull out the liner you don't want and install the one you do.


Allen