Tuning Sig Sauer Mcx Virtus pcp regulator

It's a bolt with the head drilled I used a left hand thread drill ( bolt extractor ) I also drilled out my magazine chain and put O rings in each chain so they hold the pellets instead Of the 4 plastic flutes that damage the pellets , also changed a few other things inside (can't help myself I'm always tinkering with something in the workshop)

Also swap the trigger spring for a larger diameter one and it solves the UK trigger issue, no more pushing the trigger forward to reset befor you take the next shop , the gun has alot of issues but they can all be worked out

Hope this helps others Mark Hall
 
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Thanks for the pic. I belive the gun is made by Tokyo Marui. The size of air tube and inlet looks large enough to handle any TP increase.

I have picked up a .22 semi auto since I bought the Sig .177s so I will see if I can tune up one of those first. Thanks for the info, hopefully I can reciprocate once I crack it open. I have the set up to make parts if I need to. I will also see if I can get some seals, gasket, oring...from Marui or a US outfit. I appreciate the info and pics.

Cheers
if its tokyo marui they are THE top tier airsoft manufactuer. so these guns should be solid but ive read endless reviews of issues with them. Im interested in the mpx gen 2s. Any info on those? Also how are the inner barrels held in place on these? Ive worked on a bunch of aeg airsoft rifles and im wondering how similar they are. I was looking at one of these sigs as a entry level pcp.
 
How do you measure the Regulator Bar?
Sorry for the long absence..
I bought an adapter which makes ASA airtanks to fit a 88g co2 cartridge thread. As if wanna put the airtank on a co2 rifle.
But instead I took a bar of steel and drilled straight thru it. Then made rhreads at both ends. The adapter in one end - and a gas pressure gauge (from a welding gas tank regulator) in the other end. Kind of an DIY pressure tester. Has worked well, and the quite large gas gauge gives quite well readable readings..
Sorry. No pic of it fully. But it is just a bar of iron with a gauge and the adapter threaded in..
IMG_20220604_225917.jpg
 
Hi all

New to all this as I have only had a break barrels in the past with beefed up springs.
However looking to purchase a MCX .22.

So from reading all above am i thinking that... I can modify and add shims to improve positive power up front

Now the part im confused at is there has been mention of a regulator thats higher pressure at 1450 or 1500psi

is this needed as well as the shims or is a case of do one or the other?
So far @

@nrktkt

@Lokijk82

What are you both seeing power wise now and has the rifle continued to be a working system to this day once upgrades
 
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hello here.... just acquired a sig virtus pcp.......been playing with power increase.....anyone had the striker/hammer pieces out?.... im wanting to increase hammer strike a bit ...adding one bellville to the reg, increased fps by 76 .....jsb 13.4 gr went from 660 to 736 when i added one bellville to the stack......one is all that would fit on the spool, and still fit the oring back on....
 
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accuracy got immediately better .... cool toy with lots of potential for improvement........if i dont tear it up tinkering......gotta tame that trigger pull some as well. And also, from where can the replacement air tank and externally adjustable regulator b had? im looking for near 800 fps out of this guy. fired 90 rounds so far after the reg mod. werks good
 
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hello here.... just acquired a sig virtus pcp.......been playing with power increase.....anyone had the striker/hammer pieces out?.... im wanting to increase hammer strike a bit ...adding one bellville to the reg, increased fps by 76 .....jsb 13.4 gr went from 660 to 736 when i added one bellville to the stack......one is all that would fit on the spool, and still fit the oring back on....
If you want to increase the hammer/firing pin's valve striking distance a bit longer you only need to unscrew the firing pin outta the rear of the hammer and make a slight recess (preferrably a flat recess done with a milling machine, but an ordinary drill surely also works) into the rear of the hammer so the firing pin goes in slightly deeper. Not too much though. The firing pin's rear head still needs to act as a guide for the hammer spring's telescopic housing. AND: the hammer has a significant front-back slack to it as original when all parts are assembled. Try to leave a remaining wee bit slight slack there, so that the hammer spring housing + hammer + firing pin chain does not put pressure on the valve stem when it is uncocked.

My og reg BVwasher stack was )()()()()( which gave around 1100psi.
With 0.50+0.10+0.10+0.05 (0.75mm total) added shimming I was about at 1520psi. The 1.8k disc has held that for a long time now.
..But now, after polishing my BVwasher surfaces and having a total of 0.80 of shimming (only switched out the 0.05 to a 0.10), I have miraculosuly dropped my reg pressure down back to 1450psi again.. 🤣 I've now been out to test higher pressures due I'm suspecting my hammer hits hard enough to overpower a more resistive (by the valve pressure) valve stem..

BTW.. A too hard hammer spring tension and too high valve pressure may lead to the breaking point of the valve stem's rear which the hammer is hitting. The valve stem's rear holes takes out so much material that it is not left with much thick material left to withstand really hard hits. Happened to my Virtus' valve stem, and I also know two other similar cases..
 
Hi all!

I recently purchased one of the Sig Virtus Pcp rifles and have been very pleased with it. I have had only one issue with it where I had an out of round pellet that worked its way forward in the magazine belt and bound up at the chamber. Easy fix, just needed to seat the pellet back into the belt with a range rod. After having fired close to a thousand pellets through it I was impressed with how smoothly it shot and it is surprisingly consistent with most pellets that I have run through it ranging from 14.3 up to 18.21gr H&N Barracudas, some cheap Crossman premiere and some Nelson slugs. All of them shot well and group well. The only thing I felt was really an issue was the power, or lack of. I would not suggest what follows if you are not experienced with pneumatics, regulators, and gunsmithing. I decided to open the rifle up and inspect the action and operation to decide if it could handle a bit more power. After inspecting the internals and tolerances I felt like it would handle a few more psi from the regulator and slowly started to increase the output by rebuilding the Bellville disc spring. I started by adding a single twenty thousandths shim to the base of the stack which bumped it up about 40 psi at the output. It was an improvement, but I still felt it could use a bit more. After trying a few different configurations of disc and shims and testing the psi output of each I settled on adding one disc and one shim to the factory stack and ended up at 1480psi. For me it is a marked improvement over factory, it is much harder hitting and I have had zero issues with "flyers" or inconsistencies with accuracy which had been my main concern with increasing the output. This rifle was never designed to be a long range tack driver, more of a fun plinking gun. That said it has a ton of potential for improvement and in my experience benefits from a little increase in power. For now I am pretty happy that it will hold 1moa out to 50 yards, I haven't set up a known distance range farther than that yet for better testing. But you can bet as soon as I get my chrono back from a friend that has been borrowing it I will get out and do some more accuracy tuning and report back with a more detailed update on its performance if there is any interest in it.

Hi all!

I recently purchased one of the Sig Virtus Pcp rifles and have been very pleased with it. I have had only one issue with it where I had an out of round pellet that worked its way forward in the magazine belt and bound up at the chamber. Easy fix, just needed to seat the pellet back into the belt with a range rod. After having fired close to a thousand pellets through it I was impressed with how smoothly it shot and it is surprisingly consistent with most pellets that I have run through it ranging from 14.3 up to 18.21gr H&N Barracudas, some cheap Crossman premiere and some Nelson slugs. All of them shot well and group well. The only thing I felt was really an issue was the power, or lack of. I would not suggest what follows if you are not experienced with pneumatics, regulators, and gunsmithing. I decided to open the rifle up and inspect the action and operation to decide if it could handle a bit more power. After inspecting the internals and tolerances I felt like it would handle a few more psi from the regulator and slowly started to increase the output by rebuilding the Bellville disc spring. I started by adding a single twenty thousandths shim to the base of the stack which bumped it up about 40 psi at the output. It was an improvement, but I still felt it could use a bit more. After trying a few different configurations of disc and shims and testing the psi output of each I settled on adding one disc and one shim to the factory stack and ended up at 1480psi. For me it is a marked improvement over factory, it is much harder hitting and I have had zero issues with "flyers" or inconsistencies with accuracy which had been my main concern with increasing the output. This rifle was never designed to be a long range tack driver, more of a fun plinking gun. That said it has a ton of potential for improvement and in my experience benefits from a little increase in power. For now I am pretty happy that it will hold 1moa out to 50 yards, I haven't set up a known distance range farther than that yet for better testing. But you can bet as soon as I get my chrono back from a friend that has been borrowing it I will get out and do some more accuracy tuning and report back with a more detailed update on its performance if there is any interest in it.
It's awesome how people are making these more like firearms and not a glorified toy.