FX FX M4 800mm

Hi,

Im new in this forum and I’ve heard positive things about the community so I give it a shot, pun intended. I just bought the gun and Ive been studying a lot from videos and forums, BUT still having open questions.
1. Is the 800mm rifling 1/16?
2. Anybody willing to help me getting quick setup for JSB Exact King .25 (25,39 grain) pellets?

Was thinking just to go basic setup with 4 lines, 3 and 8. Those circled values. Am I on right track?
My plan is just to zero the gun for 30 or 50 meters and to have decent grouping. Going to tune it later after I get radar to measure speeds. Going to range in 5h and have no time for more research so asking for community.

Thank a lot!
 
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Is it a full power version gun ? I don’t see a location in your profile so why I ask. No idea about the rifling. I am assuming by the settings you listed 3 must refer to the micro ??? If so 3 is way too high for the reg pressure that will required for 25.39 out of an 800 mm barrel. You will need a very low reg pressure. Most people buying the 800 setup do so to shoot heavy slugs. The long barrel provides a long runway for the projectile to accelerate thus allowing slugs to get to a high velocity. Hopefully others will chime in as it may be difficult to get that setup to run well with such light ammo. I assume the 800mm liner probably also has a twist rate more conducive to slugs 🤷‍♂️ not positive though. If it were me I would get a shorter barrel to run that light of 25 caliber ammo.
 
Shoot it with the way it is now at your target range at 30 or 50 yard/meter to see what kind of grouping and result you're getting at the range. if you're getting shotgun-like grouping at those range, you can try to fly blind and move the Micro Wheel down, or up...from 3, to see if there's any improvement to be had, leave the valve in line 4. If you're stacking dime size group at those distances, then leave it as is, no need to tune or change anything unless you plan on using different projectiles.
 
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Is it a full power version gun ? I don’t see a location in your profile so why I ask. No idea about the rifling. I am assuming by the settings you listed 3 must refer to the micro ??? If so 3 is way too high for the reg pressure that will required for 25.39 out of an 800 mm barrel. You will need a very low reg pressure. Most people buying the 800 setup do so to shoot heavy slugs. The long barrel provides a long runway for the projectile to accelerate thus allowing slugs to get to a high velocity. Hopefully others will chime in as it may be difficult to get that setup to run well with such light ammo. I assume the 800mm liner probably also has a twist rate more conducive to slugs 🤷‍♂️ not positive though. If it were me I would get a shorter barrel to run that light of 25 caliber ammo.
Hi.

I live in Finland. Yea my plan is to go slugs for long distance shooting. But for now In breaking it in and learning. So what you recommend to dial in for wheel and thumb roll?
 
Shoot it with the way it is now at your target range at 30 or 50 yard/meter to see what kind of grouping and result you're getting at the range. if you're getting shotgun-like grouping at those range, you can try to fly blind and move the Micro Wheel down, or up...from 3, to see if there's any improvement to be had, leave the valve in line 4. If you're stacking dime size group at those distances, then leave it as is, no need to tune or change anything unless you plan on using different projectiles.
Ok thank you.
 
The question is why would anyone buy a 800mm .25 cal to shoot 25gr pellets? People need to stop following Matt dubb and south African guys. Monkey see monkey do isn't always the best. My 2 cent

I have the 25 cal in 600mm and it can shoot the 25gr jsb over 1100fps if I wanted too. But it's not always about power. The 25gr pellet is more accurate at 830-860 fps. So 800mm barrel? 😆
 
Not sure what bar his reg is at, but 800mm is a little bit more forgiving than 500 or 600mm as far as valve dwell time goes, 800mm has much longer runway so it could handle just a little bit longer valve dwell time without too much issue when he is trying to adjust things before shooting it, but it's very inefficient and ineffective to tune an airgun without knowing what kind of grouping he is getting and what velocity those JSB is flying at.

There isn't any proper "dialing in" since nobody know IF his M4 is even out of tune to begin with, giving him some random ballpark settings is pretty much throwing some random stuff to the wall to see what sticks....proper tuning doesn't work that way, he most likely would just end up throwing the tuning out of whack to randomly adjusting things before he shoots it. 😅
 
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Oh, and do I need to cock the weapon when filling the tank, or just keep it uncocked and safe? Theres no mention about it anywhere.
So what are the settings now regulator, macro, micro, valve and have you shot over a chronograph.
We did more tuning today before range. 290m/s (951.4 fps)setting, and new scope zeroed. Hits accurately. Well as good as flimsy table and crappy sandbag allows to.
50 meters first grouping.
Gun feels amazing, shooter is just bad.
grouping.JPEG
 
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Oh, and do I need to cock the weapon when filling the tank, or just keep it uncocked and safe? Theres no mention about it anywhere.

We did more tuning today before range. 290m/s (951.4 fps)setting, and new scope zeroed. Hits accurately. Well as good as flimsy table and crappy sandbag allows to.
50 meters first grouping.
Gun feels amazing, shooter is just bad.
View attachment 508610
880-915 I got best results with 25gr, the 33.95gr were better at the higher end 910-920. the 33.95MK2s were better in the wind.
 
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880-915 I got best results with 25gr, the 33.95gr were better at the higher end 910-920. the 33.95MK2s were better in the wind.
Yea was tuning it bit top end so I can shoot 33.95's. Im going to switch for the slugs and long range shooting after I get bit more familiar with this new platform. Also low temps 5 degree celcius and high humidity, some might get my point.. Im going to invest for better optics in the springtime, so now I am using some semi cheap 500 dollar scope, one reason for pellet shooting also.
 
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The question is why would anyone buy a 800mm .25 cal to shoot 25gr pellets? People need to stop following Matt dubb and south African guys. Monkey see monkey do isn't always the best. My 2 cent

I have the 25 cal in 600mm and it can shoot the 25gr jsb over 1100fps if I wanted too. But it's not always about power. The 25gr pellet is more accurate at 830-860 fps. So 800mm barrel? 😆
First of all, when I start tuning my gun, theres a reason why Im doing it. I have searched countless videos all over the platform and precisely tried to pinpoint important stuff. As far as Ive seen theres people going all-in with blingy stuff and surely you understand that it has nothing to do with whats the best option. Its selling the stuff.
Im more focused on real deal and as a beginner of airguns, I might not have THE knowledge, and I am learning by doing and testing.
If I would like to have my gun fully blinged up with all kind of excess weight and someone just tuned it for me to shoot perfectly slugs in 300m, what I have learned? That my wallet got thin and i need to squeeze the trigger while xhair is on top of my target.
My point is, I dont care what other people do, I do care that I am mastering my tool as good as I can.
Im starting lower settings, grains, going up, testing, learning, and when I know the basics I start going thru the learning towards bigger picture.

I want to thank everyone of you giving me help and ideas. Im taking my first steps. :)
 
I hope one day I’m in a financial position where I can refer to a $500 scope as semi cheap 😄

Welcome to the hobby, I’m not an FX guy but definitely keep a record of your results! Hope you can zero in on the perfect tune (y)
Using Hawke Vantage 30 WA IR 4-16x50 SF 22lr Subsonic. Ofcourse prices may vary, but here its around 500. Thats ok for some distances.
 
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Using Hawke Vantage 30 WA IR 4-16x50 SF 22lr Subsonic. Ofcourse prices may vary, but here its around 500. Thats ok for some distances.
Hawke makes great airgun scopes also most Athlon scopes are good from my experience. for sure you get what you pay for (in most cases). My highest quality scope is an Element Nexus. Keep us updated on your tuning progress and ammo choices.
 
Been annoyed to hell and back since I would like to have top mount bipod, and if its under rail attachment, then 45 degrees lean on legs, but all of the options adding weight and unwanted moving parts.. Then I had an idea.. I had my sons backyard blaster Gamo HPA MI IGT and started to wonder.. They are amazing! Even cheapo but quite good giving that topmount bipod features a bit and even they a bit flimsy compared to 500e legs, they actually great. Good shooting height.
pod.JPEG
 
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Pretty cool. If you're going to use it as a bench gun the extra weight of the extended top rail is actually an advantage. I too don't want a lot of extra weight.

View attachment 509011
Good looking setup Sir. Sidemount bipod adds that direct line of support towards the scope rail, and thats what I am after to. Also option to move them bit backwards to add space for pocket fx chrono. I have not yet field tested how the shift of CG is going to chance stability and accuracy.