FX Impact M4

Valve rod/housing and plenum orings changed I think due to 15 warm up shots issue. Other than that I’m not aware of anything. Love mine (after a lot of tinkering and fiddling, fixing the slow shot issue). Best part to me is the trigger. Absolutely awesome. Don’t like tolerances/QC on some parts, like holes off center but threaded and screws into it anyway. Take apart 10 times and the threads will be gone… you’ll want CF liner sleeve. Reg creeping 4-5 bar over night, polished it up now no more creep. Great gun now, very accurate and consistent. Swapping liners is easy and cheap compared to a new barrel so you can get a new one relatively cheap if you draw a blank in the lottery. Also indexing easy, can’t do that with a lot of barrels.

1. By new from Utah Air
2. Have UA:
a. Add a top rail that protects the barrel assembly.
b. Add a bottom rail that allows you to set a bipod correctly.
c. Add a Saber Tactical butt
d. Add the scope they advise
e. Tune the rifle for the distance they advise.

UA are experts in building, tuning, and shooting Impacts. The average AGN poster can just barely be classified as an amateur.

It would be nice to see a head to head comparison between the M4 and the Leopard.

Biggest downside for hunting are the slow first shots. I know people have come up with remedies and fx was working on it, however I’ve not read or heard anything definitive to indicate they have started putting anything different into new guns. Even if so I’m not sure how you would know the gun you buy was changed. For hunting and plinking I wouldn’t dive headfirst into the expensive saber upgrades. Get the gun use it stock and see what your personal needs are first. Expensive tuning . They aren’t that hard to get good especially with pellets for the average shooter.

zerochance said:

I'm either looking to buy new or used. From launch date to now, were there any changes in the Impact M4 that I should be worried about? In example, early versions of the Umarex Notos, it did not have a degassing grub screw. New versions of the Notos now has the degassing grub screw.

Lastly, tell me why you either hate the M4 or love it. Looking for pros and cons. Main goal is to hunt small game with it. When small game isn't in season, plinking.

Click to expand...

They fixed the top rail from the m3 and deleted a regulator (that's a personal preference thing) as the most noteworthy changes to me. If you change the top rail and put huma regs in an m3, you can use some other accessories depending on where you want to go with it and maybe save some cash.

I bought early on the m3 and they did a bunch of rolling updates that I had to buy, which came stock just months later. My advice is never buy an fx model that hasn't been out a year, unless you like to tinker and spend a lot of money.

Having lived with my impact a while, if I buy another it may be an mk2 or x that I can put some of my m3 parts on. I also wouldn't do 700mm again for my uses.

I might even try and talk you out of an impact (and I love mine) depending on your intended uses and performance wishes.

Troy Bakel said:

1. By new from Utah Air
2. Have UA:
a. Add a top rail that protects the barrel assembly.
b. Add a bottom rail that allows you to set a bipod correctly.
c. Add a Saber Tactical butt
d. Add the scope they advise
e. Tune the rifle for the distance they advise.

UA are experts in building, tuning, and shooting Impacts. The average AGN poster can just barely be classified as an amateur.

Click to expand...

Better yet just add UA to your bank account, tell them to do what they want, and charge you whatever they want. The main thing is to avoid the mistake of learning what gun and accessories suit your needs and your intended purpose. Do not attempt this youself. This is no place for amateurs. If you cannot learn to shoot well, they can pull the trigger for you too. When the M5 comes out in 3 months you can always re-sell the m4 for 60% of what you paid if you pay the shipping.

cmatera said:

Better yet just add UA to your bank account, tell them to do what they want, and charge you whatever they want. The main thing is to avoid the mistake of learning what gun and accessories suit your needs and your intended purpose. Do not attempt this youself. This is no place for amateurs. If you cannot learn to shoot well, they can pull the trigger for you too. When the M5 comes out in 3 months you can always re-sell the m4 for 60% of what you paid if you pay the shipping.

Click to expand...

Agreed on ua. If you aren't chasing competition pellet shooting control of variables or high power slugs, there's other sleeper fx models I might look at.

There are other brands than FX, the M4 is not the ultimate super duper rifle ever made because FX says so.

Jay308 said:

There are other brands than FX, the M4 is not the ultimate super duper rifle ever made because FX says so.

Click to expand...

I know, but im staying in ops lane. I erased a bunch of tangential opinions in this post. haha

Lads, he asked about an m4 and pros and cons… no need for unsolicited “FX bad” comments unless there’s an actual con you wanna point out. I’m the first to bash them for their dubious methods to push their rifles, lack of QC in some areas and pretty blatant “there is no war in Ba Sing Se” attitude towards known issues. That said, the guns are still top notch. An m4 is cheaper than Daystate/BRK equivalents and a bunch of others. Plenty of parts available if something goes wrong. Yes, it’s a tinkerer’s gun and probably not a good first PCP, but that’s because of the infinite adjustability. If you know your way around PCPs and/or are willing to go slow and read up first before pulling out the screwdriver you’ll be fine.

For what it’s worth, when I have non-Airgun buddies shooting my PCPs, 6 out of 10 will say they like the impact best. And that’s after they shot Red Wolf, Ghost, AGTs and RTIs. And the other 4 split between the others. There’s a reason impacts are usually up there in the rankings. Yes, they crazy competition ones decked out way beyond stock, but you need a good platform to start with to make that happen. Stock impact, CF line sleeve and a good and indexed liner, a nice tune not pushing the gun to it’s limit and you’ll have a fine rifle…

Jay308 said:

There are other brands than FX, the M4 is not the ultimate super duper rifle ever made because FX says so.

Click to expand...

The OP knows this… where was “super duper” anything mentioned?

zerochance said:

I have a FX Maverick and it shoots great. I'm just not a fan of the double reg. I have the Panthera Hunter Compact and the quick tune system is nice. With owning the two, I know that I would like 1 reg, a bullpup, and the quick tune system. Seems like the Impact is perfect. I'm looking to set the M4 up to shoot some fx hybrids at around 900fps then turn down the macro wheel to shoot some pellets. I'm wanting the compact version in either .22 or .25. Not quiet sure which one yet.

Click to expand...

If those are your needs I’d look into the Leopard. I got a DRST that is shooting amazing and the barrel is more rigid. Tempted by the Leopard myself… not sure about power though, hybrids at 900 out of a compact might mean you’ll have to push it somewhat harder, which I personally don’t like. Prefer 5 FPE less and a butter smooth shot cycle.

zerochance said:

I have a FX Maverick and it shoots great. I'm just not a fan of the double reg. I have the Panthera Hunter Compact and the quick tune system is nice. With owning the two, I know that I would like 1 reg, a bullpup, and the quick tune system. Seems like the Impact is perfect. I'm looking to set the M4 up to shoot some fx hybrids at around 900fps then turn down the macro wheel to shoot some pellets. I'm wanting the compact version in either .22 or .25. Not quiet sure which one yet.

Click to expand...

My compact .25 wouldn’t do what you are wanting to do with any 500mm FX liner. I got it to do what you would like to do by building a 560mm LW barrel for it. On the flip side, after a year or so of barrel flip flopping, liner changes, choke vs no choke experiments, then some additional trickery, my M3 compact .22 is my favorite gun. It’s ridiculously accurate with slugs, but it won’t shoot anything but a MRD pellet on that reg setting. If you’re just going to be content with Ok accuracy with one or possibly both projectiles, then your dream of a switch gun Impact might be a reality. Your reg is going to be set pretty high to get Hybrids in either caliber to get you in a window to work with slugs. With a .25 the reg setting is in the upper window of where you can have a good tune with a pellet. Problem is, their 500mm barrel won’t do it. Switch to a slug twist liner and the pellets don’t like it. Good luck.

zerochance said:

Right… and if it’s not achievable in .25 I’m ok with going down to a .22. The expansion from hybrids should be good enough even if I take a chest shot on a squirrel/rabbit.

Click to expand...

I actually never compared hybrids in .22 and .25 at the same pressure out of the same gun just different caliber. However, I have 700mm .22 and .25 barrels for the m4 and the tune sending 34gr slugs in .25 at 920ish sends 30gr in .22 at around 910. Same 4gr difference as for hybrids in .22 vs .25. I guess .25 will be a bit easier than .22 even. I have a 15inch Evol shooting 22gr pellets at around 900. Reg is at 2,150 psi / 150ish bar to do that… so I’m guessing you’ll need at least 135 bar to get your hybrids to 900 out of a 500mm barrel, which may already be too much for stock hammer (mine starts valve locking at around 135b with the stock hammer). Which is perfectly fine for an impact, just not a “super smooth and calm” tune

I have had a .22/700mm Impact MK2 for years now (bought it new when they were first available). No problems, very pleased with the platform and it's performance.

Like you, I use mine for hunting, plinking and occasionally some pesting. I shoot mine in factory stock configuration, you just need a suitable scope.

As for the MK4, it's been out for a while, there's newer platforms available, so you might find a good deal on one.

If I didn't have the Impact I would take a close look at the Leopard. I doubt there will be an Impact "MK5" as FX is constantly improving their airguns. The Leopard has the best features from the other PCPs from FX.

Cheers!

greenbeans said:

I actually never compared hybrids in .22 and .25 at the same pressure out of the same gun just different caliber. However, I have 700mm .22 and .25 barrels for the m4 and the tune sending 34gr slugs in .25 at 920ish sends 30gr in .22 at around 910. Same 4gr difference as for hybrids in .22 vs .25. I guess .25 will be a bit easier than .22 even. I have a 15inch Evol shooting 22gr pellets at around 900. Reg is at 2,150 psi / 150ish bar to do that… so I’m guessing you’ll need at least 135 bar to get your hybrids to 900 out of a 500mm barrel, which may already be too much for stock hammer (mine starts valve locking at around 135b with the stock hammer). Which is perfectly fine for an impact, just not a “super smooth and calm” tune

Click to expand...

Unless they changed something inside the M4, both my .22 and .25 M3 compacts can easily find their plateau speed at 150b.

Vetmx said:

Unless they changed something inside the M4, both my .22 and .25 M3 compacts can easily find their plateau speed at 150b.

Click to expand...

Yeah I was surprised as well when I figured that I’m locked at 135ish. Then looked into it and found a bunch of others who also reported to be maxed out with stock hammer anywhere between 130 to 140b… not a big deal and a gram or two more hammer will solve, just something to consider…