Tuning Sig Sauer p226 x5 C02 valve mod

sig.1601585014.jpg




This post is for anybody with a Sig Sauer P226 X5 C02 pistol. This mod might work for the cyber gun or a regular p226 but I have only done the mod on my X5. It was actually not very difficult. However, I do want to say that I am not responsible for any injury you my have or cause from these upgrades. It does make the gun very powerful. I am able to sink pointed pellets well over an inch into normal 2x4s.

Originally I wanted to run HPA to get the consistency and power up on the gun. However after many attempts to find an HPA adapter, and trying to build my own, I was at a loss. Next I tore the gun down and pulled the valve apart to see what could be done here. The valve is very easy to disassemble and bore out. After the mod I am getting well over 500fps from my hand gun. It is a C02 hog and its LOUD. However it is well worth the cost for this. It is just as powerful if not more then my MCX. If any body is interested in this mod please let me know and I can give you step by step instructions as you can mess the nylon o-ring up if you disassemble the valve wrong. But its completely free and only requires basic tools, a hand drill, with a small (1/8in) drill bit and some attention to detail. 

Other mods I have done are - vent holes to help with C02 freeze up on fast firing, and venting for over heating of the C02 causing the hammer to not be able to push the valve in. Stiffened up the blow back spring. I know this doesn't improve power, and in some cause can actually take power from the gun. Well it does on this gun because with the added power of the valve work, a stronger spring keeps the valve open longer and all the semi auto actions work correctly. Lastly the barrel on these is loose from the factory. Its not bad, as it looks to be designed this way and it seals when the gun fires but it does cause the gun to seem very inaccurate. The gun its self is accurate, but with this problem it SEEMS inaccurate. The barrel locks up when fired but this can change where the sights were pointed.

Just a bit of work and this is now a very powerful gun that is pin point accurate. The two main problems most people have with the gun. Honestly I think Sig could have shipped out the gun from the factory this way but this gun would be illegal in any areas where a gun over 500fps is considered a firearm. So by keeping the valve restricted a bit they can keep the power in the 350fps range, making it legal everywhere. 

My next challenge will be to do the same mod to my MCX, however from research I believe this is a bit tough to disassemble. If anybody has torn down a C02 MCX, and has any tips please let me know. :)
 
OK - here are the instructions.

1.) Remove c02 cover and c02 if one is in it.

2.) Remove retaining pin by trigger and slide. Back of valve should be exposed. 

3.) Using a large flat head screw driver remove back of valve like a normal bolt. Be carefully as its spring loaded, not alot but it will unspring when you get it out. 

4.) Pull the spring and valve shaft out of the valve. You will be drilling 2 places on the valve. 

5.) Using a drill bit the same size as the oblong hole on the side of the shaft put the drill bit in the hole and hone this out larger. Be careful as you can go too much but you can get away with about a mm larger hole. 

6.) Throughly clean shaft with acetone. The lowest acetone percent female nail polish cleaner works great. 

7.) On the valve housing there will be the c02 inlet. Pull the valve housing out. Hone this out as well. Again be careful as you can go to much. But 2mm larger hole should be great. 

8.) Clean valve housing with acetone. Throughly.

9.) Re assemble valve housing to gun. I would replace any rubber orings at this time but it's not necessary. 

10.) Reinsert valve saft. Now when installing the nylon oring apply just a little bit of greese on the oring. Moly is best. When screwing in the back of the valve go slow and make sure the oring sets correctly. Tighten down tight but not superman tight. 

11.) Re assemble slide. You can also upgrade the large slide spring because your gun will have more kick now. I hate the loose spring they put on these guns stock. The slide just moves around to easy. Any hardware store will have a good spring. But you might have to test a bit because if it's to strong of a spring the semi auto won't work.

12.) Put a bit of moly on the slide where it rubs any metal to metal. Just a little bit of greese.

That's it. It is alot of steps but you will see its not very hard if you take your time and stay clean. The physics of how this mod works is flow. Because c02 is a standard pressure depending on temp, you must get more c02 through the valve while it's open. I got my sig to penatrate over an inch in a 2x4 with this mod, with a nice tight slide. 

I also did hamer and hammer spring work on my mcx which is now hpa and regulated at 1800psi. I'm getting 12grain pellets to about 1000fps if you have an mcx or mpx I can help you with this as well. Just an FYI I build high performance air guns aso a side hobby and for pretty cheap for friends and what have you. If you ever need anything please let me know.



Also I am not responsible for anything that may go wrong while you do this mod. It's easy and safe but I have to say that. :)



Thanks!


 
  • Like
Reactions: DOOMRIDER
Oh yeah one last tip. If you are shooting in colder weather, below 70 degrees, wrap a hand warmer around the c02 and then insert in your gun with the hand warmer around it. You can get these really cheap at walmart in the camping stuff. It will keep your c02 around 95 degrees for like 8 hours and your gun shootin at full power even in blow 0 weather. Just a cool trick I use. :) 
 
Yes it is the newest x5. Yes you can totally cut that area out. I don't have pictures as I did the work like a year ago. But I am happy to help and answer any questions you may have. What type of power are you looking for? There are several options in that price range and some are set up to produce more power then others at least easier and more straight forward. Also FYI you can get a X5 on amazon or pyramid air right now and shipped to you in a few days if that's an option for you. :)
 
The x5 is c02 and really can't be converted to anything else. Its fine at first but quickly ( even with the valve work ) I wanted more power. You can choose an equally nice gun ( like a full metal Bretta for the same price, but you can easily upgrade it to HPA and with some valve and hammer work you can get in the 800 fps range no problem. The sig will not ever be able to do this. And for just a bit more you can get a Hatsan at-p1 https://hatsanairgunsusa.com/product/at-p1-pistol/ that right now are only $229 close out. Its a $500 pcp pistol brand new! I have this pistol as well and it has a fully adjustable hammer and has some unbelievable power and accuracy. More then a 22 when I crank up the hammer spring. Plus Hatsan has GREAT support as well. So there are options. :) But if you want a nice c02 gun and it will stay c02, get the sig its a really nice gun.
 
  • Like
Reactions: monstr2