Tuning FX Impact M3 35 cal power destiny
- Thread starter 7Green
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A quick google search pulled this up:
https://www.capitalrubberco.com/
A quick look through their website shows this:
https://static1.squarespace.com/static/5af9da44e2ccd1e909568721/t/5b4f9660aa4a990c17302daf/1531942505899/Ragco-Catalog-compressed.pdf
So, they might have what you need. I admire your willingness to problem solve your situation with your new gun. I am also in Northern CA as well, and it's great to see there's a few serious air gunners around. I will post updates once I get my M3 back and I have a chance to shoot it a bit. Although the gun is expected back Friday, there's a possibility I may be evacuated from the Caldor Fire by then, so it may be a minute before I have results. I do have a .30 cal 600mm conversion kit in hand, and will be testing that on the .35 M3 in the near future as well.
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This is certainly an appealing dream. The struggle with making 200 ft/lbs with the .35 M3 will be the limit on mag length. The Nielsen 93's are the biggest that will fit, so to get to that power level, they're going to have to be going 985 fps. I like your dream, and I'll admit I am struggling to envision the gun doing it.
I am going to be happy if when mine comes back, it's pushing the 93s at 865 fps with FX level accuracy for a mag or two. If so, I am going to leave it alone, and my tinkering will involve step downs to .30, .25 etc, spinning nobs and wheels, and leaving the inside alone. That is my dream.
By comparison, I have a Bulldog I have modified with a bigger TP, Huma Regulator, etc that puts out 220 ft/lbs, but the mag fits the Nielsen 142s, and they're moving at 835-840. It is a much less refined gun, and I get five accurate shots per fill. It was a simple gun to tear down and modify, and if something goes awry, the whole gun has fewer parts than the M3 has o-rings.
I like your dream though.
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Hopefully you are spared from the Caldor fire. Fires this scale never really happened growing up here, but that is a different discussion involving politics. I'm actually going to be working it tomorrow for around a 15 hour shift.
I am big pretty big into hunting, fishing, and archery/shooting. I drive my wife nuts with how involved I can get in my interests and hobbies some times. Now I just got to find myself a buck or two for my D tags lol.
I went ahead and ordered some O-rings off amazon to get me back in the game. FX has already shipped the parts too, so hopefully everything gets resolved. I would love to see 870 fps NSA in the 93 grainer.
I am big pretty big into hunting, fishing, and archery/shooting. I drive my wife nuts with how involved I can get in my interests and hobbies some times. Now I just got to find myself a buck or two for my D tags lol.
I went ahead and ordered some O-rings off amazon to get me back in the game. FX has already shipped the parts too, so hopefully everything gets resolved. I would love to see 870 fps NSA in the 93 grainer.
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Well, when I got home tonight my Sekhmet gauges showed up, so I installed them and replaced the blown o-ring. 
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yes!! i really like the sekhmets; have those as well and a few of the huma digital one's as well. The sekhmets are in a class above.
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So today I installed the two washers with the 9 gram brass hammer installed. If you remember, I also recently shaved the rod the C1 connects to slightly so it would measure 5.5 mm off the frame. My hammer now has close to 3 grams over the weight from the one the wrong one gun came with. Below proves parts make a big difference.
I set the macro wheel at 16, micro adjuster set as far as it will go for the gun to engage the sear and the valve adjuster opened up to imaginary line 6 or so. 170 bar 1st reg, 152 bar 2nd reg. Any higher or lower reg pressure and I lost 5 to 10 fps. Peak speed with 81 JSB's was 926 fps with most around 921 to 923 fps. 93 grain NSA's showed 844 fps, but I only was able to shoot a couple because I am out. I would not doubt some may hit 850 fps if I had more to test.
If you recall I hit 835 fps with NSA's and 909 fps with JSB's previously.
I ordered some more 79 and 93 grain NSA's, which have already shipped. I purchased some in .356 and .357 sizes to try.
In summary, my theory is proving it takes more hammer weight to open the valve with high reg pressures. The distance/space beween the hammer and sear is limited. With heavier hammer weights, you gain hammer length, which limits the micro adjusters availability of travel adjustment. Mine is currently only able to go to 3.1 or so before it peaks, due to the brass hammer's length. I wonder what material FX uses for the hammer? A denser metal, which weighs more may prove to be beneficial, as would lighter valve adjuster spring or heavier hammer spring. Perhaps a smaller spring inside the hammer spring and to the rear of the hammer weight would aid in even more hammer spring power...hmm.
My next purchase is going to be the Huma 2nd stage reg, as the FX one seems finicky past 140 to 145 bar. Hopefully Huma will come out with a first stage one soon too. Past 155 bar on the 1st stage and the reg gets finicky too, as it bounces up way high before dropping back down slowly.
I set the macro wheel at 16, micro adjuster set as far as it will go for the gun to engage the sear and the valve adjuster opened up to imaginary line 6 or so. 170 bar 1st reg, 152 bar 2nd reg. Any higher or lower reg pressure and I lost 5 to 10 fps. Peak speed with 81 JSB's was 926 fps with most around 921 to 923 fps. 93 grain NSA's showed 844 fps, but I only was able to shoot a couple because I am out. I would not doubt some may hit 850 fps if I had more to test.
If you recall I hit 835 fps with NSA's and 909 fps with JSB's previously.
I ordered some more 79 and 93 grain NSA's, which have already shipped. I purchased some in .356 and .357 sizes to try.
In summary, my theory is proving it takes more hammer weight to open the valve with high reg pressures. The distance/space beween the hammer and sear is limited. With heavier hammer weights, you gain hammer length, which limits the micro adjusters availability of travel adjustment. Mine is currently only able to go to 3.1 or so before it peaks, due to the brass hammer's length. I wonder what material FX uses for the hammer? A denser metal, which weighs more may prove to be beneficial, as would lighter valve adjuster spring or heavier hammer spring. Perhaps a smaller spring inside the hammer spring and to the rear of the hammer weight would aid in even more hammer spring power...hmm.
My next purchase is going to be the Huma 2nd stage reg, as the FX one seems finicky past 140 to 145 bar. Hopefully Huma will come out with a first stage one soon too. Past 155 bar on the 1st stage and the reg gets finicky too, as it bounces up way high before dropping back down slowly.
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You got past my numbers with the jsb pellets with similar settings but I didn't have the extra weight. I wonder how the .356 will do with those settings. More importantly will be how they group once you get those slugs in.
I am going to look at 75 and 50 yard groups going forward because those are the farthest I would shoot while hunting with a .35 air rifle. I know it can reach out further but for hogs or other big game that's my distance limit; 50yards and in would be more my ideal target range. Definitely keep us informed on how it goes because what your doing does matter. Thanks again and as soon as I get mine back I'll be joining in with more testing...
I am going to look at 75 and 50 yard groups going forward because those are the farthest I would shoot while hunting with a .35 air rifle. I know it can reach out further but for hogs or other big game that's my distance limit; 50yards and in would be more my ideal target range. Definitely keep us informed on how it goes because what your doing does matter. Thanks again and as soon as I get mine back I'll be joining in with more testing...
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Will do. I plan on using it on coyotes and turkey hunting here in CA. Currently, we can't use airguns for big game hunting here, which is pretty ridiculous, being the power some air rifles have now days.
It has been a journey, lots of testing, and a lot of ammo...lol. I may order a spare pellet probes in the future, so I can try modding some for better air flow. That is unless FX comes out with a slug power kit in the near future.
It has been a journey, lots of testing, and a lot of ammo...lol. I may order a spare pellet probes in the future, so I can try modding some for better air flow. That is unless FX comes out with a slug power kit in the near future.
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Another thing I noticed and will start paying more attention to soon, is at this setting the gun uses about 4 or 5 bar a shot.
In theory a full mag will burn approx. 90 bar for 18 shots. At a full fill, it would put shot count around 18 to 20. More testing will be needed to confirm this, as it was just something I noticed.
Also when analyzing data for the 81 grain JSB's,
130-135 bar 2nd reg yielded 880's to mid 890's with wrong oem valve parts. Low 900 to 905 fps with NSA slug probe installed. Very neglible difference and may have been in the tuning.
130-145 bar with a 9 gram brass hammer weight, no washers, and NSA slug probe, yielded slightly better fps and peaked at 909 fps.
150-155 bar with 9 gram hammer weight, two washers installed (9.86 grams total weight when combined), and NSA slug probe, yielded 926 fps peak.
An approx. 20 bar increase netted 20 to 30 fps gain with the NSA slug probe installed.
Regarding efficiency, I have know idea how long the valve remains open during the shot, nor do I know how much of the air in the power plenum is being consumed during the shot cycle. However, there is 15-20 bar with the factory 2nd reg still available and maybe more with the Huma reg installed. The trick will be figuring out how to open it at the higher bar level to gain even more fps/fpe.
Following the aforementioned logic, the extreme Huma goes from 135 to 200 bar. If one were to purchase a new 300 bar rated air tank (simply for the sake of shot count), there may be the potential to fling the JSB's at 1000 fps if you could get the valve to open at 200 bar. This could also put the 93 grain NSA's into the low to mid 900'-950 fps range.
Just some food for thought.
Once I get the correct valve internals, I will be weighing, and measuring them, plus hopefully coming up with more ideas after I test them out.
In theory a full mag will burn approx. 90 bar for 18 shots. At a full fill, it would put shot count around 18 to 20. More testing will be needed to confirm this, as it was just something I noticed.
Also when analyzing data for the 81 grain JSB's,
130-135 bar 2nd reg yielded 880's to mid 890's with wrong oem valve parts. Low 900 to 905 fps with NSA slug probe installed. Very neglible difference and may have been in the tuning.
130-145 bar with a 9 gram brass hammer weight, no washers, and NSA slug probe, yielded slightly better fps and peaked at 909 fps.
150-155 bar with 9 gram hammer weight, two washers installed (9.86 grams total weight when combined), and NSA slug probe, yielded 926 fps peak.
An approx. 20 bar increase netted 20 to 30 fps gain with the NSA slug probe installed.
Regarding efficiency, I have know idea how long the valve remains open during the shot, nor do I know how much of the air in the power plenum is being consumed during the shot cycle. However, there is 15-20 bar with the factory 2nd reg still available and maybe more with the Huma reg installed. The trick will be figuring out how to open it at the higher bar level to gain even more fps/fpe.
Following the aforementioned logic, the extreme Huma goes from 135 to 200 bar. If one were to purchase a new 300 bar rated air tank (simply for the sake of shot count), there may be the potential to fling the JSB's at 1000 fps if you could get the valve to open at 200 bar. This could also put the 93 grain NSA's into the low to mid 900'-950 fps range.
Just some food for thought.
Once I get the correct valve internals, I will be weighing, and measuring them, plus hopefully coming up with more ideas after I test them out.
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Thanks for sharing that information and testing different configurations with your gun. My gun is suppose to arrive back to me tomorrow from FX USA according to the tracking info. It is doubtful I will be able to contribute to the great testing info you're building here for quite some time. AQI is currently 700 in my neck of the woods and evacuation warnings have hit the basin today. I am expecting they will switch to mandatory in the next 48 hours for my area. Keep up the good work, and I look forward to contributing some data to this thread as soon as I am able.
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No worries. I hope it all works out for you. The good thing is heat rises and there is a lot of granite at the summit, spreading the timber out some. Falling ash and hot embers, combined with wind would be the worst.
I will continue to update my findings as time allows.
I will continue to update my findings as time allows.
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Another consideration I am having is adding an additional external plenum, but will wait until test other ideas first. I found some at
https://foxairpower.com/collections/parts
Also, and just so everyone knows, Huma does make a 1st stage reg for the gun and are in the process of making a compact version.
https://www.huma-air.com/FX-Impact-Dual-Stage-Tuning-Regulator
https://foxairpower.com/collections/parts
Also, and just so everyone knows, Huma does make a 1st stage reg for the gun and are in the process of making a compact version.
https://www.huma-air.com/FX-Impact-Dual-Stage-Tuning-Regulator
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I am not sure if you've seen this video on the front reg rebuild, but this is the route I will go first. It's a solid step by step for improving front reg performance:
https://www.youtube.com/watch?v=MZ5aiSOze74
Just spoke with FedEx in Sparks and deliveries into my area of the basin aren't happening today and perhaps not for a while. Actually a good thing, as it's one less thing to pack and one less distraction.
https://www.youtube.com/watch?v=MZ5aiSOze74
Just spoke with FedEx in Sparks and deliveries into my area of the basin aren't happening today and perhaps not for a while. Actually a good thing, as it's one less thing to pack and one less distraction.
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Yes, watched the video but sent the rifle back because I didn't want to damage the block; have all the tools around except a vice to hold it. He did a really good job and explained in very good detail...
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Just an update, as I haven't posted in a bit.
I am currently researching getting the hammer parts made out of Tungsten. The FX is limited on space, so what better way to gain weight than with density.
I am also waiting on other parts to arrive before I conduct any more testing.
Below is a drawing I made for the parts I am trying to procure out of Tungsten.
I am currently researching getting the hammer parts made out of Tungsten. The FX is limited on space, so what better way to gain weight than with density.
I am also waiting on other parts to arrive before I conduct any more testing.
Below is a drawing I made for the parts I am trying to procure out of Tungsten.
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Thanks for the update. I called FX this afternoon and they haven't started on my rifle yet but they just received it on Thursday so didn't expect them to get to it yet.
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Maybe I missed it but have you tried adjusting the hammer spring to coil bind ? Is that even possible ? I have an Impact X and have never needed to because it’s a .22. I’ve built a few big bores in my day and I typically use a 2/3 hammer weight in grams to desired FPE . Example
300 fpe goal = 200 gram hammer . I do this for a couple reasons although the numbers are an exaggeration . First is that using an extremely stiff spring is hard to cock especially with a bolt type action and second , I use long barrels and having the extra dwell from the big weight really helps make power.
I personally think the impact is tapped out at the 30 caliber. Or about 100FPE . Too many small parts in there that I’m not comfortable pushing beyond the limits. I wish you luck on your quest for big power.
300 fpe goal = 200 gram hammer . I do this for a couple reasons although the numbers are an exaggeration . First is that using an extremely stiff spring is hard to cock especially with a bolt type action and second , I use long barrels and having the extra dwell from the big weight really helps make power.
I personally think the impact is tapped out at the 30 caliber. Or about 100FPE . Too many small parts in there that I’m not comfortable pushing beyond the limits. I wish you luck on your quest for big power.
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