FX M4 impact issues

If you haven’t noticed, nobody who has responded has had one that delivered right out of the box, me included. But we all kept ours for various reason. Me, I wanted to figure the thing out and try to see if it could be what it should be. Others like to tinker and I’m sure some are just so in love it doesn’t matter how many time she cheats on him. Either way, you have to decide what camp you’re in. Or if you just want to hunt and do other stuff with your free time.

Edit: I was not singling out anyone. Just speaking generally from what I’ve observed over the years about this gun.
 
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I feel like I got some work to do. Idk if I want to upgrade a new gun that should be awesome out the box! But i have no doubt there are some out the box special guns out there! My wife would blow a gasket if I start buying parts for this new gun lol. Might have to cash out some of my XRP crypto position for these upgrades
Do you like assembling a gun that uniquely suits you or do you not enjoy tinkering on your machine? Honest question. The last guy I talked to this about wanted it tuned out of the box perfectly, and I told him I didn't think fx was for him, maybe the raw hmx 1000 . Fx is a box of really good, expensive machine shop parts with potential that happens to shoot pellets well out of the box.

Pellet life is simpler and more fun I think too. I set my gun up for slugs and by the time I got them to shoot well, and consistently the gun kinda got heavy, long, and over specialized. When it was set up for jsb heavies it happened to shoot some lighter patriot slugs super well too.
 
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If you haven’t noticed, nobody who has responded has had one that delivered right out of the box, me included. But we all kept ours for various reason. Me, I wanted to figure the thing out and try to see if it could be what it should be. Others like to tinker and I’m sure some are just so in love it doesn’t matter how many time she cheats on him. Either way, you have to decide what camp you’re in. Or if you just want to hunt and do other stuff with your free time.
Mine was fine out of the box. Watching south african infomercials convinced me it wasn't. I fell for it.

Edit. I honestly feel I made the gun less enjoyable after I fell down the south African high power slug rabbit hole. Right in the 40 grain 22, 700 and 800mm era.. Had I left It Alone I wouldn't have bought a dreamline just to shoot pellets. They got me.
 
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Mine was fine out of the box. Watching south african infomercials convinced me it wasn't. I fell for it.
The only one I bought as a pellet shooter was great out of the box for over six months. Then I lost my mind on it too. But I will say that before I even shot it as a pellet gun, I tore it down fixed the slow shots issue and blueprinted it. Now the gun is a test barrel gun and one of my favorite squirrel but maybe something bigger guns.
 
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Mine was fine out of the box. Watching south african infomercials convinced me it wasn't. I fell for it.

Edit. I honestly feel I made the gun less enjoyable after I fell down the south African high power slug rabbit hole. Right in the 40 grain 22, 700 and 800mm era.. Had I left It Alone I wouldn't have bought a dreamline just to shoot pellets. They got me.
Great points. I'll have to learn this gun and find some tear down setup videos or work instructions on the m4 or older models. With having a house full of girls I find my self in the work shed alot these days! I have 5 girls ages 3 to 15! The 8yr old loves to tinker so might let her fix the raptor reg rebuild!
 
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After all the things I did, I can let the gun sit for a month and crack off an oddly specific 93 yard pigeon shot with a light slug just below the speed of sound with regularity and not get in trouble for sketchy stuff.

Key is plenum Pressure consistentency, 2nd put a spacer behind your shroud that let's you tighten the shroud against the body. Now you have a tensioned barrel. I bought the carbon tensioner and it's no better than the collar I machined... But it's extra weight and money that a 1 dollar part already fixed.
 
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The only one I bought as a pellet shooter was great out of the box for over six months. Then I lost my mind on it too. But I will say that before I even shot it as a pellet gun, I tore it down fixed the slow shots issue and blueprinted it. Now the gun is a test barrel gun and one of my favorite squirrel but maybe something bigger guns.
Got a picture of your rig? Mine was having poi issues in the field during a hunt!
 
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Got a picture of your rig? Mine was having poi issues in the field during a hunt!
What are you guys hunting and what typical ranges and projectiles?

I shoot a lot of pesky birds and rodents for right now, turkey this spring hopefully and coyotes when i get a chance and maybe quail with the garbage rod before season is up.

Dreamline tactical compact 25 on pellets for the closer in varmint and bird work.

700mm m3 impact 22 for the 100 yard and beyond stuff. 23gn javelins and 31gn Nsa at the moment on 1 tune.

Aea hpss 22 "garbage rod" on hades for rabbits and rats
 
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After all the things I did, I can let the gun sit for a month and crack off an oddly specific 93 yard pigeon shot with a light slug just below the speed of sound with regularity and not get in trouble for sketchy stuff.

Key is plenum Pressure consistentency, 2nd put a spacer behind your shroud that let's you tighten the shroud against the body. Now you have a tensioned barrel. I bought the carbon tensioner and it's no better than the collar I machined... But it's extra weight and money that a 1 dollar part already fixed.
Got a picture of your spacer? I might look into fabing some stuff on 3 axis Haas mill
 
Got a picture of your spacer? I might look into fabing some stuff on 3 axis Haas mill
Lemme look. I just measured the shroud to action gap and added 20 thou on a piece of brass pipe I had and made sure the faces were parallel and tried it, then aluminum was made. No more barrel shift from rough handling. I have the carbon harmonic tuning shroud over a carbon tensioner with a carbon stiffener now 🤣. If you know the meme "cahbahn piebah"
 
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I apologize in advance. I realized that this is the only pic I have of that spacer if you zoom in.

20220612_092530.jpg
 
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Lemme look. I just measured the shroud to action gap and added 20 thou on a piece of brass pipe I had and made sure the faces were parallel and tried it, then aluminum was made. No more barrel shift from rough handling. I have the carbon harmonic tuning shroud over a carbon tensioner with a carbon stiffener now 🤣. If you know the meme "cahbahn piebah"
Hey I can work with that!
 
Lemme look. I just measured the shroud to action gap and added 20 thou on a piece of brass pipe I had and made sure the faces were parallel and tried it, then aluminum was made. No more barrel shift from rough handling. I have the carbon harmonic tuning shroud over a carbon tensioner with a carbon stiffener now 🤣. If you know the meme "cahbahn piebah"
I did the tensioning thing in my Impact infancy. If the material used does not match the temperature expansion and contraction of the block and shroud, instant POI shift. But mind you, I’m sitting in the woods when the temp starts in the 40’s and swings up into the 70’s or vice versa. Now I just use real barrels and all that other barrel crap can stay in a box somewhere.
 
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I love it. As a tool and die trades man I like it!
I'm a bit of a millwright these days but a finish carpenter to buy the toys. Find the 1 off parts 😁. Middle one is Bone stock.

I bought the m3 when it came out, then they sold everybody in the powerblock during the 40 grain and 800mm push. I mic'd the power block and the stock one and realized it had less internal volume, less machine work and cost me more. The rolling concurrent generation upgrades are slightly annoying.
I did the tensioning thing in my Impact infancy. If the material used does not match the temperature expansion and contraction of the block and shroud, instant POI shift. But mind you, I’m sitting in the woods when the temp starts in the 40’s and swings up into the 70’s or vice versa. Now I just use real barrels and all that other barrel crap can stay in a box somewhere.
That's why I went from brass to aluminum to delrin and then just got the carbon tubes and it was OK even in 115 degree ambient temps and direct sun southern ca heat. It's the day I started hating my impact changes for the weight when i pulled off an offhand 150 yard squirrel shot.

20241205_164158.jpg
 
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We shall see how it suffers in the cold. Apparently it didn't mind the heat expansion. My gun also has the tensioning block and top strap attached to the action with larger diameter socket head cap screws, due to my pulling threads,which I forgot. I think the shroud tension and liner stiffener could be imparting some insulation value and lack of thermal expansion to the mix. The aluminum shroud could've been a problem.
 
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Mine was fine out of the box. Watching south african infomercials convinced me it wasn't. I fell for it.

Edit. I honestly feel I made the gun less enjoyable after I fell down the south African high power slug rabbit hole. Right in the 40 grain 22, 700 and 800mm era.. Had I left It Alone I wouldn't have bought a dreamline just to shoot pellets. They got me.
I started with two MKll PP Impacts and continued on with a M3 until I finally built what I wanted. But it was basically a powder burner. I found I didn’t shoot it much because well, I guess mission accomplished. But I will occasionally find a new use for it just to shoot it. Like hanging a feeder at 130 yards and picking mice off it at night. Or long bombing pests when I’m too lazy to stalk them. So like you said the gun was less enjoyable. I figured I better build two other Impacts in two calibers that were more conservative power wise that I can enjoy all aspects of airgun hunting. They are still dialed in for first shot kills way beyond 100, but they really shine for 75 and under hunting. And when I say build, I’m not talking ordering bolt on junk from a dealer and calling it a build.
 
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So I should have waited a year before trying this platform! Gezz should have bought a brk ghost or hw hunter or evol! Well thats life!
Then there would be an Impact M5 to consider…🫣 Why does FX not simply make an Impact G2? Where all the issues of the G1 Impacts up to, an including the M4 are addressed? The G2 Impacts would be simply a platform to build upon, not something to trade “up” from as is the current status. Which devalues all the prior models markedly… The Ghost? BRK got it right, it is simply a solid initial gun. No, M 1, 2, 3, 4 designations necessary…
 
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We shall see how it suffers in the cold. Apparently it didn't mind the heat expansion. My gun also has the tensioning block and top strap attached to the action with larger diameter socket head cap screws, due to my pulling threads,which I forgot. I think the shroud tension and liner stiffener could be imparting some insulation value and lack of thermal expansion to the mix. The aluminum shroud could've been a problem.
Heat never got me. Cold did. But I found a way of tensioning that allowed for it when I thought tensioning was necessary even with a real barrel. But over the last year, I abandoned it. But I will never say I won’t go back to it. It just depends on how happy I stay with how things are now.