FX Impact M3 .357, in the search for more umph

Ok, lots of questions and no need to get frustrated, it is all pretty simple.

Yes, you will need a heavier hammer setup to open the valve at higher pressures. 135 to 145 bar should be plenty to throw 81 grain pellets in the 850 to 900fps range.

You also should only have 2 rubber balls in the valve adjuster knob.

What weight hammer assembly (hammer + hammer weight) are you using? All together in grams. A picture would help of you assembly.
Thank you for all the replies. I had really tried to make sure the “c1” was set to 6-6.5. I used my depth finder on caliper’s for this. I’m assuming it’s Millimeter’s. I was more at 6 with a tightened “c1” but the video I was watching with Ernest Rowe, he said make it 6.5, so I loosened it a bit. The C1 was so loose at this point I could just use my fingers to adjust. I got it spot on 6.5 and that is what it was on before disassembly. The hammer and hammer weight and two washers and a spring with 1 ball came in a pack with the barrel and probe, those are what I put in. The new hammer (the big hollow tube looking thing) does not has the plastic o ring on it, and I’m pretty sure the hammer weight also does not have plastic on it, the spring is the same one as before and there are also the two washers. All of that is the new hammer assembly. The new C1 has a plastic ring on the end. I did mare the rod a bit with vise grips, so I used the very fine (polishing) sand paper from my knife sharpening kit to polish the marring of so as for the rod to be smooth to the touch again. That and I put the hammer in backwards the first time and had to figure out why the gun wouldn’t shoot. Those are my only big mess ups on this project. And now that they are corrected I can’t see why I have less FPS than before. Maybe I’m missing a second rubber ball in the lighter weight valve spring that came with the barrel? As far as I can tell it only came with one. Thank you all for being so supportive. I will try to post more info/pics within the next few days. Chemo is kicking my butt at times so I sleep a lot.
 
No worries, take care of yourself first.

My C1 is at 5.25 to 5.5 if I recall. You don't want it loose and I use a dab of blue locktite when I reinstall it. I just heat it up briefly with a "tweeker torch" before I take it off each time. 5.5 to 6.5 mm is fine.

The valve opening is more Conducive to the weight of the hammer assembly and the spring behind it.
 
You will want your macro wheel on 16, once we get your hammer setup figured out.

The Micro dial will not go to 5 and that is ok, perfectly normal. Just set it near where the max adjustment is, minus a click or 2 so the sear engages and cocks the gun.

When you take it apart again, please contact me before you reassemble it. We need your C1 measurement to hit 5.5 to 6.5mm. It will need to be tightened down with a dab of blue locktite or nail polish added.

I have a bunch of hammers and I will mail you a heavier setup/design if needed, just private message me your address. I have done so much trial and error, I highly suggest you read my power destiny posts and this entire thread. They will help you understand the gun as you take it apart and put it together.

When the gun is apart, measure your hammer spring too please. I am curious what length you have.
 
7Green, I am also using the Huma 57mm spring (#1308) and I also just recently noticed a 20 fps drop (1070 to 1050) on my velocity. I'm only running 170 on the regulator so I could see why your drop would be more at 180 or 190 reg. I have one used spring that I took out of my MII a year ago that measures 55.37mm that has shrunk over time. I will remove the one presently in the gun and see how much it has shrunk to verify that it is the cause of my velocity drop.

I pulled the spring out and replaced it. It had shrunk to 52 mm. What I do now is keep the power wheel on Min. when I am not using the gun so that there is not so much preload on the spring all the time.
 
Yeah, it is a bummer that they lose power over time. I just replaced mine and threw in a 16gram tungsten hammer today to try out. Getting 885fps at 170 bar with great accuarcy out of a standard superior barrel. I left the stock valve adjuster spring in too. I know I can get more, and may try for it when my heavy liner comes. May need an even beefier spring though to do it consistently.
 
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Another idea I have is deleting the hammer weight and instead have the hammer itself made out of tungsten. Then the hammer spring may be able to take a really beefy spring. I wonder what the hammer itself would weigh in at. You could even lengthen the skirt portion some to achieve a desired weight and help guide the springs compression. Currently stock oem hammer is around 19.5 grams. I still have one in brass that is 23 grams and one with a tungsten insert I made.

Just ideas
 
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Commenting to save this thread. I been reading all your posts around this forum.

I have a 700mm .25 that has the bullet Central tensioner and shroud, Saber Tactical Trs rail with a 3d printed barrel clamp I made to fit the BC shroud.

Just got my hands on a power block. And before I put the power block on I was debating on doing hammer spring and hammer weight.

I was shooting 33.5g slugs at 1015fps before with a 145bar second reg. I recently found the oring on the back of the liner was missing. I'd like to move up to 36-40g slugs at similar speeds.. but maintain some sort of air efficiency. I just hate taking the gun apart more than I need to (takes away from spending time on my drag car lol).

I have not got to shoot since I added the barrel tensioner and installed the missing o ring. Also switched the the superior heavy liner. So I may have picked up speed with replacing the missing o ring.

I just need to figure out what spring and weight to get. You changing the hammer adds a variable that's hard to account for. I don't think I should have to go that far to sling a 40g slug at those speeds. But would like to get those speeds with everything working together at modest settings