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All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: 7Green on August 20, 2021, 01:45:35 AM
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Hello all,
I am curious as to what speeds others are getting with their FX Impact M3's in .35 caliber. If you own one post up your speeds, 1st and 2nd regulator settings and valve adjuster settings.
A little history from my personal expierences so far...
Currently I have fired well over a 1200 rounds between 81 grain JSB's and 93 grain NSA's in the .357.
When I first started, the gun came from the factory firing JSB's at 880 fps and the NSA' were 790 to 800 fps.
I began playing with various 1st and 2nd regulator pressures. In summary, what I discovered was:
-My gun has less regulator creep when the 1st and 2nd regulator are within 10 to 15 fps of each other.
-My gun loses velocity if I up the 2nd regulator pressure above 135 + bar. I have tried numerous 1st and 2nd reg settings to confirm this.
-The fastest I could get 81 JSB's with the factory pellet probe was 894 fps.
-The fastest I could get 93 NSA's was around 820 fps.
-With the NSA slug/pellet probe my velocities increased to a max of 905 fps for the JSB's and 835 for the NSA's.
-As I have shot my gun more and as the speed increased, the NSA's started grouping far better than initially. Initially they were around 2" groups at 50 yards. Now they are an inch or under at times.
End summary.
Today I confirmed my hammer will not open at higher regulator pressures. This was with the valve adjuster two full turns out from line 4, the power wheel set on max, and the quick tune as far as the gun will let me while still engaging the sear (about setting 4.6). I then adjusted the first regulator to 170 bar and the 2nd to 155 bar. My goal was to see if the hammer would open the valve and add velocity or deduct velocity.
With 93 grain NSA's it shot 798 fps to 805 fps at 155 bar.
I had also previously tried 155 bar on the first regulator and 145 bar on the second regulator, which showed a loss of velocity or around 795 fps to 805 fps.
When I set the first regulator back to around 145 bar and the second back to 135 bar, I get 825 fps to 835 fps. At the same setting the 81 grain JSB's go 900 fps to 905 fps.
What I discovered was anything past about 135 bar on the second regulator and the velocity drops. The hammer settings are maxed out, which leads me to believe the hammer isn't striking the C1 hard enough to open at higher pressures.
As for the C1, I have it set as far as it will screw on the valve rod, which measures 6.13mm off the frame. I also took the gun apart to make sure the opposite end of the valve rod wasn't un-screwing and it was fine. While apart, I checked for damage on the o-ring and valve sealer piece. Both were good to go and looked great. Afterwards, I relubed the O-rings and put the gun back together. I am getting really quick and good at that part now (lol).
I weighed the hammer pieces and washers too. Each washer was .43 grams with the main portion at 6.13 (part #C55) grams. Part # C54 was 18.13 grams. All combined I have a total weight of 25.12 grams.
The hammer spring (part # C56) measured 52mm long with 18 coils, if you count the very end ones on each end.
Currently I am seeing a peak power around 140 to 143 ft/lbs. I have read of people using the Mk2's and getting 870 to 900 fps with 93 grain NSA's, so I am bewildered. I have plenty of power for shooting JSB's but I would prefer to shoot slugs and a little faster. It has been grouping them quite nicely, which I think would even get better as the speed increases because it has so far.
My goal is to achieve at or above 155 ft/lbs with NSA's, so I can take advantage of the BC slugs have to offer. I am currently thinking I may need a heavier hammer to open the valve at a higher pressure. The JSB's shoot one ragged hole at 50 yards or around 860 fps, but that isn't my goal.
So with all that mentioned, please post up any results you all may have with the same gun and the settings or adjustments you have had to make to get the performance you desire.
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Today I conducted another test and here were the results. Bare in mind my goal is to find peak power and get to the guns peak ratings.
In summary this is what my gun does:
Hammer set to 16, micro aduster around 4.6 as that is peak for my gun, valve adjuster two full turns past line 4 to imaginary line 6.
-1st reg 145 to 150 bar, 2nd reg 130 to 135 bar.
Speed up to 905 with JSB's 81 grain. Speed up to 835 with NSA 93 grain.
-1st reg 185bar, 2nd reg 140 bar.
Speed up to 884 with JSB 81 grain. Speed up to 814 with NSA 93 grain.
-1st reg 185 bar, 2nd reg 150 bar.
Speed up to 879 with JSB 81 grain. Speed up to 800 fps with NSA 93 grain.
-1st reg 200 bar, 2nd reg 140 bar.
Speed up to 888 with JSB 81 grain. Speed up to 814 with NSA 93 grain.
-1st reg 200 bar, 2nd reg 150 bar.
Speed up to 879 with JSB 81 grain. Speed up to 800 with 93 grain NSA.
-1st reg 200 bar, 2nd 160 bar.
Speed up to 872 with JSB 81 grain. Speed up to 798 with 93 grain NSA.
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This confirms my theory that the hammer isn't using enough force to open the valve past 135 bar.
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Another thought I am having is are the two rubber balls and/or the piston stop needed inside of the valve adjustment knob. Parts C45,C46 AND C47. I am wondering if the valve would open more should anyone of of the three be removed.
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I also have two custom brass hammer weights to try out, but I am waiting to speak with FX customer support before I dive into that.
The oem part (# C55) is 27.8 mm long and weighs 6.13 grams bare with no washers. The washers add .43 grams each.
The brass ones I had made are 7.67 grams bare and 9 grams bare with no washers. The 7.67 gram one is 28.44 mm long and the 9 gram one is 29.91 mm long.
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The general thought is I can swap hammer weights from a factory 7 grams, using the factory washers and increase the weight to nearly 10 grams if needed. I am trying to get the valve to open above the peak 135 bar my gun is currently limited at, so I can increase the speed of the 93 grain NSA slugs.
If anyone else has experience in this matter, please post up. Otherwise, I will continue my detailed log until I do or don't achieve my goals.
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I haven't messed with the M3 specifically, but I'd say you're certainly correct about needing more valve strike/hammer weight.
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7Green, to give you a little encouragement I just finished power tuning a new M3 .35 cal. for a friend that asked me to build him a banger. I set it up to shoot the FX 81gr. pellets at an average velocity of 925 ft/s for about 154 ft. lbs. muzzle energy, and an avg. V of 927 ft/s with the 79gr. NSA hollow points for about 150 fpe, and an avg. of 842 ft/s with the NSA 93gr hollow points for about 146 fpe.
All the best, Chuck
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Bump
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7Green, to give you a little encouragement I just finished power tuning a new M3 .35 cal. for a friend that asked me to build him a banger. I set it up to shoot the FX 81gr. pellets at an average velocity of 925 ft/s for about 154 ft. lbs. muzzle energy, and an avg. V of 927 ft/s with the 79gr. NSA hollow points for about 150 fpe, and an avg. of 842 ft/s with the NSA 93gr hollow points for about 146 fpe.
All the best, Chuck
Hey Chuckster, sound like you get together with PM 7Green and let him know the setting to achieve 154 ft. lbs. with the JSB's ;).
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Hammer set to 13, micro adjuster around 4.3 valve adjuster 0,5 turns past line 4.
-1st reg 165 to 170 bar, 2nd reg 130 to 135 bar.
Speed up to 890 fps with JSB's 81 grain.