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
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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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