It’s a semi automatic weapon so it won’t reset the hammer! That is moved back with the operation of the trigger each pull of the trigger pulls back the hammer till it’s fully depressed then it is released forward..!

So i have my main valve leaking in to magwell. I have four new washers and i was wondering if i should glue the aluminium centerpiece so it wont get loose? Or should i just put the washer and the centerpiece in like so and see what happens?

How can i press off the nylon washer from the rear of the valve? I didnt know it was pressed with the metal piece and i took only the nylon washer away. Now i have four new nylon washers/seals that i want to test if i get the gun back in bussiness but i dont know hot i can add the nylon washer in without taking off the centerpiece EDIT: Seems like it was very loose and i got it off just by pulling

hopefully it is fixed

I'm wanting to paint my mpx to a coyote brown. I figured I would take it apart and paint what I wanted with some rustoleum. While I had it opened I was gonna clean and oil some parts. Should I just use pellgun oil? Is there any pitfalls I need to be aware of before opening it?

hi! Can I turn this gun into a fully automatic PCP? My fingers hurt and I'm tired.

Stripped mine down and i have a pin that i found on the belt interface nipple (LOL) hoping you could identify it

The internal metal looks like some kind of zamec type alloy, really weak, shame, if they used 7075 aluminium alloy with better seals, gun in theory would be much more reliable and last much longer.

I've had my MCX sitting around for a year now due to a leak, and this video gave me the courage to open it up and get to the bottom of it! Thank you for both parts, good to have a no bullsh*t guide to follow. Saying that I couldn't find any obvious issue, just gave everything a clean and applied some Pellgunoil to the seals and it seems to be working great (only fired 1 magazine so fingers crossed). Edit for anyone wondering, the innards of the MCX appear to be near identical to the MPX.

I just did all this and the thing just spit out a whole new 88g canister. It started with a bit of a sputtering of co2 after a couple shots and a slow leak, after taking it apart and putting it together it just spit it all out without stopping flow. This thing was such a waste of money

Pot metal and dreams hold these together. I am surprised they shoot at all.

Mines leaking from the big white o ring where the pin punctures the co2.. it sprays out right by the slide hammer

My mind keeps going to the idea that maybe replacing some parts with a more robust metal but say im right and we replace aluminium mechanical parts with steel parts how will that affect the momentum and timing of the function

Did you say "put your ❄️ in there"?????

Ok so the sig mcx mpx are pretty awesome but they need care. To start you got to out the charging handle before you can shoot it. Pellets need seating correctly or they won't shoot right. Never shoot with co2 and no pellet running through it. Last thing that should be said first is the pcp thing. I have been around a while now and hear from a lot of different people about these. The biggest issues i have seen is they always break on pcp, get a double 12g adapter its better suited. If that broke after just 3 months i would have returned it instantly, not sure how Scotland works with returns but in England we get a full year. My sigs come with lifetime service and repair so i got lucky, also i have never had any issue with mine

Hi, thanks so much for your video on the Sig MPX/MCX. Really clear and useful. You mentioned a fondness for the ASG TAC Repeat which I’m about to try and improve. Even with the metal magazine I feel it could put out a fair few more fps. I wonder if you have time to produce a tear down video look at this air rifle? I have one in full working order and three broken ones I bought as junk from which I can use the parts. Thanks again for the Sig expose. Regards, Baz.

Nice my only have 300 rounds and my won’t feed .

The "Chatter" is the hammer not resetting on the sear. This is a "blow back" system. Its the same principle used in low quality paintball markers. They scavenge some air from the air that fires the projectile to also reset the hammer on the sear. Some areas to check are the point of interaction between the hammer and sear. Look for excessive wear where the sear touches the hammer. If worn, the hammer may slip off the sear several times before catching. These blow back operating systems are also sometimes dependent on back pressure. The pressure used to reset the hammer is higher when there is a pellet being fired. The force required to push the pellet causes the "back pressure" used to also push the hammer back to the sear. If therer is no pellet, there is no resistance on the air flow resulting in less pressure to reset the hammer. This causes the hammer to repeatedly strike the firing pin because its not bing reset, its free floating back and fourth. Also, Co2 losses air air pressure if fired repeatedly. The faster you release Co2 gass, the lower the pressure in the tank becomes untill it warms back up in a few moments. This loss of pressure can cause the hammer to not reset also. However, using HPA will alleviate that issue. Back in the hay day of paintball, I worked as a gun technician from 2000 to 2015. I've repaired 1000's of paintball markers and the functionality of this gun is no different. If your gun is firing more than once on its own, the hammer is striking the valve more than once because its not catching the sear. The cause could be one of a few issues. I dont believe its possible for the valve pin to "chatter" on its own. I hope this helps.

This MPX is configured the same as my MCX but my issue is a bit different. With about 300-400 rounds through the MCX v.1 CO2 air gun, it out of nowhere, stopped firing. Unlike this and other similar reviews I have read, mine is not an issue with pressure leaks or the hammer popping out of the bolt. It took a long while to determine but it appears that the hammer, when pressed in at the factory, is pressed to a very specific depth (from the front of the bolt). Thus, the hammer had not been seated against the bolt, leaving an additional amount of space before the hammer would actually seat against the bolt. My suspicion was that during the initial 300-400 rounds, the impact of the hammer against the firing pin, finally pushed the hammer deeper into the bolt. Now, having increased the distance between the hammer and the firing pin, it prevented the bolt/hammer mechanism from actually contacting the firing pin. I popped the hammer out of the bolt and added a washer of 1.4mm thickness to the shaft of the hammer then reinstalled it back into the bolt. The MCX is now back to firing. Extremely poor engineering. Shame on you Sig.

I disassembled the gun, fixed the pin and closed everything again.. now the trigger no longer seems to do its job well.. did I do something wrong? thanks for the reply in advance

Great video very helpful thank you

Could you do a video on how I can remove the barrel please, thank you

I was going to buy one of these but they seem to get a lot of bad comments on Reddit

Your video helped me a lot, thanks

If you buy one buy the gen2 model I brought the gen 2 mcx you can tell the difference from the trigger it’s flat on the gen2 and has m lok hand guard I have put over 3000 pellets though it and have not had 1 jam and still work very well as far as I know the upgraded the internals on the Gen 2

is there any way i can make it full auto?

would you perhaps know the nut and screw size for the shroud please? Iv'e damaged mine and lost the screws - thank you!

I am wondering if the Canebrake is the one to get. I suspect it is the 'fixed' version. Mine shoots at nearly 700 fps (just shy of 7ft/Lb) and has been fault free so far. I only use the 88gr CO2 bottles. I did find the barrel was loose after investigating some flyers, and found a bolt that was very loose. Now it is all tightened down it should be better. Have yet to test it though.

Be careful not to turn on the air while apart! I just about lost an eye! lol

Thanks! Trying to fix a leak that happened after running maybe 200 rounds through it... sigh

Nothing like a good old break barrel.

Is there a way to make it fully automatic ?

under no circumstances should yoyou take up this guy's suggestion. It will undoubtedly destroy your gun! The tip of the metal tube inside the aur chamber is designed to be smooth and provide an air tight seal. If you try shaving of the end of it, you will never achieve the perfect seal and your gun will leak. You will not be able to repair it after this. He is a liar and wants you to destroy your gun. BE WARNED!!!

I put mine back together n the trigger won't pull why is that?

I have a plan for this, I just got one, and I understand the flaws, but the gun performed well in this video. I expect mine to be the same way when I'm done; thanks for the vid. I stay looking for updated videos.

Thanks so much for the video. I had taken mine apart and some of the pieces fell out and didn't know how they went in there. You are right about the gun. It is a nice looking and had potential to be a great pellet gun but very poor as soon as you open it up. I am tired of going thru 10$ cylinders for only about 5 shots . I got an adapter that I havnt tried yet because I didn't know how to put the thing back together but do now thanks to you.

My mag jams all the time the gun works perfectly fine with mag out used the tool to seat the pellets corrected provided with the Gun, any help appreciated checked mags in good condition only had it few months 4 shots then a jam or sometimes won’t fire at all

Thanks so much for your 2 videos. great help to me with trouble shooting my problem. Your camera placement was excellent. Your commentary was great as well.

There is something strange about the way of thinking with Sig and their experiments with mcx and mpx that give bad results. I guess it has something to do with the production costs. After 5 years they have finally solved the problem with the firing pin on the mcx and mpx by serrating it, but they have replaced the brass sleeve that holds the nylon gasket in place at the back of the valve body with a sleeve made of the same crap material as the rest of the innards, so now it is this sleeve which falls out instead. This brass sleeve on the older versions was as tight as if screwed in. The older versions also had a better construction of the air supply with screw connections at the brass tube that pressed against the o'rings. It would have been better if another airgun manufacturer that takes pride in making good airguns had taken over the production rights and made the necessary improvements, then these airguns could have been really good.

I have all 3guns,all leaks air.any suggestions anyone

my black shroud has disintegrated suffice to say I am getting loads of air from the magazine and about 1fpe!! any ideas where I can get one?

The firing pin popped outta my old MCX once. Once. I put instead an M4 cylindrical hex head steel screw into it and thru it. Took off the small knob from the rear of the hammer/bolt and attached a round 6mm thick nut to lock the new firing pin and to keep the main spring front centered in place behind the bolt. That all threadlocked and it ain't coming out again. The firing pin issue, along with a new "nipple" moving lug system was developed from the .22 Virtus PCP version and forward. I'd recommend you buy next the Sig Rattler Canebrake or the now outcoming MPX gen2. I definitely now want a gen2 MCX. My Virtus has been awesome - but I'd like a new MCX in .177 with the newest internals. That old thin co2 transfer line just does not work as well with air. My old MCX I had shooting way hard once - but the co2 cooled down so damn fast that it was not fun for that long.. I really woulda wanted the .22 Sig Virtus PCP in .177 also - just because the .177 ammo is cheaper to plink with.

Might need to check the small steel ring around the rear of the valve cap if the gun won't recock itself after shots. Might leak a bit too much between the valve body and the hammer's internal wall. Way nice video. I finally got to see a good view of the MPX's barrel assembly. I just own the old MCX version. Now I'd wanna have an MPX also..😁🤣

Oh man. I love these Sigs. A definitive hobby airgun. This vid gotta be interesting ..

Great video, very very helpful, I just wished I discovered it sooner 😅

Thank you for your video and part 1 also. It helped me fix mine. The pin had fad fallen of, and the plastic spring thing was stuck in the same time.

That looks to be a mostly metal and plastic gun, not one single bit of it appears to be made of air. I can't believe you made such an egregious error, smh my head.

Wow, much interest

Based and redpilled

Great to see what you have been doing at Towford. Thank you for providing these fantastic, incredibly valuable experiences our young people.