Tuning FX Impact M3 35 cal power destiny

I did some more shooting yesterday (Sunday). After thinking about Ram2Jeep's philosophy of going with a pellet tune, this started to make sense for me at this time. Based on the amount of lead I put down range for accuracy tuning Saturday, with nothing great coming from the .357 79 and 93 gr Nielsen's, I am wondering if my barrel prefers the .358s. So I ordered a few boxes of those, and will save my remaining .357s until the .358's come in and go after the slug tune at that time. Another factor in my decision is the general season deer opener is this upcoming Saturday, and I have an Elk hunt in a month: in short, I don't have a lot of time to be tinkering with the gun in the near future.

So, yesterday I dropped the front reg to 155 and the rear reg to 138. With these settings, I can go as fast as 900 with the 81gr JSBs. I then dialed down the speed to around 888 with the valve, and I am getting pretty good accuracy. I did not arrive at a final tune before the light got too low to allow my chrono (ProChrono DLX) to pick up speeds reliably. I am at decent groups, but not super great. I think I can get it to hole on hole at 50yd with just a bit more tinkering, but I don't think I will have time again this week. I put it away in the safe for the near term. I have a modified, regulated Bulldog that shoots the Nielsen 142s with excellent accuracy and 220ft/lbs, and I think that's getting the nod over the M3 this weekend. I ended the day with a little sunset shooting of my Akela, and remembered the joy of shooting a simple, accurate, and quiet gun.

7Green: To answer your question, I am shooting off a bench with either an Accutac bipod or a bench tripod and sand bag in the rear. Off this set up, all my other guns are supremely accurate, including both Bulldogs and a Texan 457, all of which put out more power than the M3.



My short term goals are to get an accurate tune with the 81gr JSB's and then swap barrels to the 600mm .30 cal slug barrel and see what I can get to fly right with just adjusting the Macro wheel. My goal with the .35 M3 was always to get a modest amount of performance out of the .35 cal, and have a wicked .30 and .25 cal slug gun. I made some movement in that direction in the two days I've had the gun back from FX USA.I was hoping it was going to be a bit easier with the Nielsens, but the gun is performing as it should, and as noted in this thread, it may just take a few hundred more pellets and slugs down range for the accuracy to fall into place.
 
Be safe out there and our season opened last week, black bear. Deer season isnt until October and that's only bow; we do shotgun in November and primitive in December. 

@mtndragon, it's nice when at least the pellets are working well and you were able to lower the tune to achieve some accuracy. I'm keeping at it when not in the woods as this is my peace from such a hurry up world...
 
Well hopefully you have some good luck with your Idaho elk tag. I hunted CO last yr for elk out of Steamboat Springs. It was tough hunting, especially with all the downed timber from beetle kills. 

I plan on doing some more testing on the M3 too, but I may slow down some. I think volume of air at a set pressure is the biggest restrictor left. Plus, I have the NSA's shooting pretty good for me. I don't know why because when I first started they did not shoot well.

Perhaps I found a good node, the bore polished in some or I coated it with enough lead lol. There can be an infinite number of reasons. Either way, I am happy with a modest amount of power and around 20 shots or so a fill. It has been a journey and I will update this thread as I come up with new tests, it just may be further between testing as it is hunting season!
 
Best of luck with punching your tags! My next big hunt will most likely be in TX for some exotics; gotta really save for that trip though but I know it will be worth it. Again, be safe and keep is posted. 

I have some appointments tomorrow so range day is Wednesday and I will post my results. I have a few boxes of 79gr NSA so I might just throw them in the bag to see how they do with groups. Not gonna mess with my tune too much for the time being besides slightly increasing the second regulator just a touch.
 
Yeah, I will probably work on fine tuning my regulators and valve adjuster more than anything else for the time being.

Based on my last data, 157 bar should be a good starting point for the 2nd reg. I will adust the 1st reg down a bit to fine tune it and try to minimize reg creep, although the Huma reg is working extremely well and better than the factory reg. I can literally dial it a bar or 2 at a time.

It should also be mentioned after the testing I last reported, I adjusted everything and was getting fairly consistent speeds aound 861 to 863 fps at 157 bar. 
 
Hi Guys, I just found this thread ...

I have a .35 MkII and have gone through some of the same issues.

I have been through about 1000 rounds of NSA .93gr .357 and never really found a tune that the gun liked with them. I could just never get them to group.

The 81gr JSBs shoot well enough with the factory tune (870fps) that is with the regulator set at about 135bar.

While working on the groups with the JSBs, I found that at about 780fps (yes, 100fpe) the groups tightened up to sub-MOA. Oh, and with the power this low, you get 60 or so shots from a tank of air!

In all of my tuning with my .35 the pellets were always more consistent than the slugs.

I really want this gun to shoot slugs well, so I hope you find a tune that works.
 
@essington Yeah, JSB's seem to always shoot the best and are the easiest to tune. As some have mentioned, the cheapest and easiest route will be just waiting for FX to release a slug barrel. I chose not to wait and seem to have better than most lately with NSA accuracy. When I get time, I will have to stretch the legs on it some and see how good it may be. 

During one of my previous tunes with the NSA's my 11 year old was able to shoot a rabbit at close to 100 yards. I was also able to hit anything and everything I aimed at under 50 yards, including splitting the styrofoam piece from a JSB tin laying flat. 

For hunting purposes, my M3 is plenty accurate with the 93 grain NSA's. What is weird is when I first started using them, my results were less than ideal and very similar to what some have reported. I do not know if the accuracy is a result from the tune, the barrel harmonics, the way I cleaned the barrel, the speed I send them at, or the barrel polishing and breaking in.

I do know my gun has become plenty accurate with them. I am currently launching the 93 grain pills at around 860 fps and get about 20 shots a fill. I still have to fine tune the regulators and valve adjuster some. My 2nd reg is set at 157 bar.
 
7green I had an mk2 shooting .93s at 970-980fps before it broke and I threw it in a box robbed parts etc. my m3 is shooting .93 nielsens at 820fps consistently with only the Nielsen probe I modified the probe as it had some flaws…now I say 820 consistently on my m3 that is with my barrel cut about 6-7” short! Where did you get the tungsten weights and what sizes did you use I may order some swap them in with a spring from the slug power kit they sell and see where I land @7Green if you have a Facebook look me up Tyler Lott Indiana it may be easier to chat on messenger sometime and then post our data here!
F069BBFE-078E-40CB-8494-E4125E01FC0A.1634475269.jpeg

 
Nielsen .93s

823fps 

125 yard gong 4”

55 yard gong 4”

12mph wind from north west

shooting east 

Thor 4 640 thermal 

1:00pm daylight 

hand warmer taped to backside of gong at 125 yards



I cut down the factory barrel by approximately 7” my Donny fl ronin barely fully threads tight with mm to spare before hitting the end of the bottle as you can see.





ECE5EB0F-E082-4500-BD0A-84AA38919EB2.1634490951.png
51433774-06EB-4FF7-B193-BA30F3ED0FAE.1634490952.png
408592B2-076C-434E-8697-BFF7F752D54E.1634490953.png
A611677D-B08E-4FB7-AA46-74431713E72E.1634490954.jpeg
D89110D9-4EF2-4111-B1F4-B3BAB662B370.1634490955.jpeg
1B5D60C2-794A-4B3A-AF86-67BDFF0BDE6D.1634490956.jpeg
9E809999-2D25-4E86-B133-825877CA9E67.1634490958.jpeg
58198C67-79C6-4D4D-8B3E-56266CA4F343.1634490959.jpeg
F5E562E2-B166-4E7B-9827-CC0B65CA788D.1634490960.jpeg
58781213-4C5F-417E-85B5-7A544CC644DD.1634490963.jpeg



 
Nielsen .93s

823fps 

125 yard gong 4”

55 yard gong 4”

12mph wind from north west

shooting east 

Thor 4 640 thermal 

1:00pm daylight 

hand warmer taped to backside of gong at 125 yards



I cut down the factory barrel by approximately 7” my Donny fl ronin barely fully threads tight with mm to spare before hitting the end of the bottle as you can see.





ECE5EB0F-E082-4500-BD0A-84AA38919EB2.1634490951.png
51433774-06EB-4FF7-B193-BA30F3ED0FAE.1634490952.png
408592B2-076C-434E-8697-BFF7F752D54E.1634490953.png
A611677D-B08E-4FB7-AA46-74431713E72E.1634490954.jpeg
D89110D9-4EF2-4111-B1F4-B3BAB662B370.1634490955.jpeg
1B5D60C2-794A-4B3A-AF86-67BDFF0BDE6D.1634490956.jpeg
9E809999-2D25-4E86-B133-825877CA9E67.1634490958.jpeg
58198C67-79C6-4D4D-8B3E-56266CA4F343.1634490959.jpeg
F5E562E2-B166-4E7B-9827-CC0B65CA788D.1634490960.jpeg
58781213-4C5F-417E-85B5-7A544CC644DD.1634490963.jpeg



what's your shot count with running the 2nd reg up there? just curious to see. I just purchased and installed my new 700cc 300bar bottle for the .35 and my .30 Maverick with the hopes of getting a better shot count for my 81gr jsb's at 900fps with 2nd reg at 130bar.
image.1634498038.jpg

 
I am running the 2nd reg, which is a huma, around 157 bar currently. I run around 865 fps with the 93 grain NSA's and the NSA slug probe.

The weight is a 1/2oz tungsten fishing weight. I had to use my dremel, lube, and a carbide tipped bit to drill it, as tungsten is extremely hard. I then drilled out the hammer and used probed 2000 to epoxy it in. I posted all of this some where in the previous posts if you look back through them. 

I also believe polishing the valve rod or any part that is associated with the hammer assembly helps the assembly slide faster and hit harder. Less loss of energy before it contacts the c1, resulting in higher fps. 
 
I swapped in a human reg 2 I couldn’t get the huma extra high pressure reg to work tonight so I swapped the disks to high pressure (12 discs) and set about 175 bar I have upgraded hammer spring 1 spacer and brass hammer weight I also added delrin c3 spacer I am consistently getting 850-858fps with Nielsen .93s and accuracy has improved.



my question is what good is the first reg what’s its purpose? I may just remove it all together I’ve noticed the reg 2 tends to take a few seconds to fully reset and reach bar after each shot…this led me to the question is the 1st reg slowing down the 2nd? My first reg is set over 200 bar? 
 
Can you post the hammer spring specs you installed and where you located it?

I have my 2nd reg at 157 bar, but the factory spring doesn't have enough umph to open it at higher pressure. I want to open it around 190 bar. 

The main issue I see with removing the 1st reg, is you would have potentially 300 bar at the 2nd reg, should it ever fail. The max output I believe was 200 bar on the Huma reg. It would be worth checking with FX or Huma, as to what it can handle on the input side, not too mention the rest of the guns specs. For instance, can the power plenum handle 300 bar if the reg failed?

Just some things to consider. I'de hate to see a dangerous situation develope.