Sig MPX gas port & tapit

[Nimitz]

How often are you all having to take apart the gas port & tapit and clean them?  After my first 1,000 - 1,200 rds there was so much carbon built up the bolt wouldn't fully close after firing the first round and the gun turned into a single shot PCC -lol.   Got the port & tapit out with some effort & cleaned them and then at last week's Steel Challenge match got to the forth stage  (~ 110 rds) and the gun started to do the same thing.  Took it apart and while the gas port wasn't clogged anywhere near like last time it took quite a bit of force to rotate & remove it and the tapit wouldn't budge either without  a lot of Hoppes #9 & force ....

Anyone else seeing this in their MPX?

[TISCHLJ]

I'm using clean powder. Vv 320 and 3n37 which helps alot. Make sure you are putting the piston and valve back in dry ...I clean the asse.blies 600- 800 rounds or so. Wh when I clean the gas valve and piston I get it cleaned up as best I can with an exacto knife and some brushes then give it a ride in some Lucas bore solvent in the Ultrasonic Cleaner with heat

[Aircooled6racer]

Hello: What type or bullets are you using? Did you check to see if the gas pistons rings are staggered so it seals? I use Tite Group and plated bullets mostly and have run 1000 rounds before I clean it. I do run a bore snake through it after a day of shooting. I also oil the bolt as well. I do put one small drop of ATF on the piston rings after I clean them. Makes cleanup easier I think. Thanks, Eric

[Neomet]

Yeah, the answer kinda depends on what you shoot.  Moly projectiles and/or dirty powder will increase the frequency.  That said I run PD 124 jacketed rounds and a clean powder and I take mine apart every 800 rounds, clean the snot out of it and change tappets.  I have four tappets and rotate them.  When one comes out it soaks for quite a while in cleaner, gets a good scrubbing/scraping and then goes back in line.  

[2011BLDR]

On 5/20/2018 at 3:46 PM, Neomet said:

Yeah, the answer kinda depends on what you shoot.  Moly projectiles and/or dirty powder will increase the frequency.  That said I run PD 124 jacketed rounds and a clean powder and I take mine apart every 800 rounds, clean the snot out of it and change tappets.  I have four tappets and rotate them.  When one comes out it soaks for quite a while in cleaner, gets a good scrubbing/scraping and then goes back in line.  

I  only shoot JHP now.. did like 8K of Speer TMJ and 2K of FMJ gas plug was caked so I ran it in the Ultrasonic for  9 hours one day and got about 25% off.. Just decided to replace it with a In Led We Trust "full open" plug and stick with JHP & N340 but moving to 3N37 now. No malfunctions but did see a increased carrier velocity when it was dirty..

Edited May 23, 2018 by 2011BLDR

[rowdyb]

I shoot sport pistol and a plated bullet. I had to use a large crescent wrench to get the port to turn, it was very difficult to turn to remove. The tappet came out with a light hit with a hammer. This was after maybe 400 rounds in total through the gun.

 

I reassembled it completely dry. We will see how it runs tomorrow. Gen 2 gun, stock barrel and such.

 

In contrast my bcg looked hardly dirty at all.

[Nathanb]

I clean mine frequently now just because the last time I took it out and ran about 2500 through it suppressed it took forever to get out.  

[Nimitz]

Thx all.  I'm shooting extreme 124s and WST.  I like the idea of rotating tappers  ... Where did u get them?  I did a quite search and couldn't find any parts ...

 

2011bldr:. What is that "in led we trust full open plug"?

 

i have some Titiegroup but am not excited about using one power for my MPX and WST for everything else - not sure how dirty WST is anyway and I don't really want to switch ,,,, guess I'll need to be cleaning more often ....

 

anyone take the the gas port apart? It looked as is like you can screw off the back side with one of those special pinch plyers - not really sure what they are actually called ..

[Nathanb]

In lead we trust specializes in mpx parts. It’s a company. 

[2011BLDR]

In led we trust = Google it..manufactures lots of after market MPX parts that can be difficult to source from SIG

[MemphisMechanic]

Im my experience WST is cleaner that titegroup anyway, @Nimitz. They both leave a handgun the same visual mess, but titegroup welds a carbon depost to steel that you need to scrape off with a chisel. WST produces much easier cleaning soot.

 

I wouldn’t choose TG over WST for this application!

Edited May 25, 2018 by MemphisMechanic

[Neomet]

On 5/22/2018 at 5:24 PM, 2011BLDR said:

I  only shoot JHP now.. did like 8K of Speer TMJ and 2K of FMJ gas plug was caked so I ran it in the Ultrasonic for  9 hours one day and got about 25% off.. Just decided to replace it with a In Led We Trust "full open" plug and stick with JHP & N340 but moving to 3N37 now. No malfunctions but did see a increased carrier velocity when it was dirty..

I am with you on the JHPs.  I experimented for a match or two with molys and the difference was really noticeable.  N37 might be a good choice.  I was thinking of trying N38 just because I like it so much in my Open guns and have it whispering to me from the closet.   

[Nimitz]

Thx,. I'll check them out ...

[rowdyb]

Just fitting by hand, the gas plug and tappet from ILWT seem to fit with less friction than the Sig parts. I have yet to shoot the gun though with all the ILWT gas parts in as my barrel is off to get it's gas port opened up.

[spt1955]

Titegroup!!!!    OMG.  I can't imagine thinking of shooting Titegroup in any gun with a gas tube piston or otherwise.  Doesn't get any dirtier than Titegroup.