any help on how many fps I should tune too when trying to shoot hybrids out of my m4 compact .. shooting around 960 .. not shooting like when I have 25 gr jsb pellets at 960 …. Factory liner
Tuning .25 cal 26 gr slug out of m4 compact
- Thread starter Yoo_andd
- Start date
It’s trial and error from my understanding to find the magic number for groups. I plan to start tuning mine and if it gives me a headache I might just go .30 cal pellets
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Try MANY different diameter slugs (costly) and weight (lenghts) and it should be noticeable which diameter slug your barrel prefers within a few shots then you can slowly tune for optimal accuracy. Order slugs of different antimony properties also.... my RAW likes NSA a tad harder than pure lead and my Taipan Vet2 likes AVS slugs which are soft....both in .22 RAW 's barrel likes .2175 diameter, and the Taipan likes .2183 diameter FYI it sometimes takes quite a few different slugs to find the one your barrel likes.....it's much different than shooting pellets for sure!
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If you have the 1:16 twist line the hybrids will work great, 1:18 and 1:24 you'll need to run them at least 960fps and hope they shoot well.
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If you get something to shoot as good as a pellet out of a 500mm, you need to post how you did it. You might be the first and it will be an honor. I’ve tried off and on for years with quite a few liners and may slugs because it mystifies me. But intitally it didn’t take me long to see the writing on the wall so I machined a real barrel for my Impact compact and lived happily ever after. But it still doesn’t stop me from testing with the fickle FX stuff from time to time in hopes of being able to help the guys that just can’t build a barrel that doesn’t fight them every step of the way. I truly wish I could even point you in a general direction. But everything I tried with the 1:16 and 1:24 sucked. At least by my standards.
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Ima try tommorow at maybe 980 tried dialing in there with my 2nd reg turned up to about 125 it’s at 120 rn.. turned to 970 had some decent shots but yeah my liner is a 1:24
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I tunes my buddies 600mm .25 to shoot 40gr at 880 and 34gr at 950 and it's consistent and quiet. About 145b on the rear reg with a 1st reg delete.
@RoosterCogburn is crazy good at tuning.
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Yo_andd
try 175/170 145/140 to begin with, find a setting on the PW, whether you want 26 @ 970 to be your high end or mid or low end, adjust your micro to that velocity at that PW setting, then work on the spreads with the valve adjuster. Low reg pressure doesn't necessarily mean high shot count.
velocity is good, but i'd try it at 135-145bar at the same speed. Valve will close before the projectile leaves the barrel
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Your saying try 170-140 on 2nd reg .. I have 1st reg delete .. and yeah I’m at 120 on second reg with pw at 16 micro at like 4.. tonight I was going to adjust second reg up to like 140 or whereever I could get it to shoot at around 970-980 but with power wheel alittle lower .. correct .. like your saying valve will close faster
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When you used the term 2nd reg I assumed you had both. So 140 145 on the reg. 120 a bit low. I can very easily hit 970 at those low pressures. But ill use more air per shot.
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I tried turning up my second reg past 130 and it won’t go any higher than like 135 130. I don’t have a gauge for my first regulator because the stock m4 doesn’t have it. .. what is it set factory ..
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Starts dropping fps after about 125 .. also what’s the difference if the set screw is out at like 4 with pw at like 6/7 or if setscrew is at like 3 with pw at like 11/12
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Its supposed to dip.when you raise the pressure. Then you raise the micro to catch up. Dont turn the power wheel to go up. Turn the micro up as the pressure goes up
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the two wheels are connected. You can get to your goal however you please. Im just accustomed to turning the pw to max or the middle and adjust with micro to get exactly where I want then dialing the wheel back %5-%7 from peak, and perfecting the spread and shot cycle with the valve adjuster
Set pw max, want 26s going 970, set velocity up to 1020 1025 at max, roll pw down until you get back to near 970. Begin shooting groups and watching chronograph, if spread is all.over. start working valve adjuster in incrementally then fire 5-10 shots. Spread still high. Another increment. Rinse repeat until the shot sounds good, groups well, and youre happy
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Willing to pay you wanna private message me a tune for .25 cal to shoot slugs . If not I’ll keep dialing in these pellets lolll
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Brother. Every impact has differences. You need to understand what your gun is telling you, there is no cheat code.
First problem.
500mm .25.
Second
.25 CAL HYBRID SLUGS. In .22 the hybrids are great, in 30 theyre great. In .25. Not so much.
Get a slug liner, get a longer barrel. Or at the least get the SLUG liner, not the heavy liner, and youll want a stiffener in the 500 stiffener and tensioner if you go longer. In 25 slug is a different liner than heavy. In your current configuration. High Bc pellets are what you want. I had my impact as a 25/500 before. The ONLY slugs I had luck with were a boutique 32gr cup base .250 at 920fps. The heavy mk2 pellet is incredible. The AEA 33.9, 29.5, 30 gr options are great and have a pretty high bc. The .25 hades is great. With the slug liner they're incredible. Push them at insane velocity for pellets with great accuracy.
I have NEVER had luck in an fx gun with .25 fx hybrids. Zeros and other snowpeak guns, uragan... yes.
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Probably not what you want to hear. But youre not going to be ripping slugs at crazy speeds from a compact. 25 putting 5 shot groups inside a dime. You CAN do this with heavy and light pellets
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Ok I have exact 25 grain pellets and those were shooting good they’ve been out of 22 cal barrel kits in 500 for like 2 months almost 3
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