Gunfixr Gas Plugs

[Gunfixr 76]

Due to issues between Mike Davidson and myself, MD Arms will no longer be producing the Gunfixr Gas Plugs.

 

Greg at Carolina SS is now producing them, and they are available from him.

 

I wish Mike Davidson all the best in any future endeavors he may pursue.

[Paulyski 2,227]

Okay, so while you're here...

 

Honestly... We have a bunch of guys that (weather they own one or not) seem to think that your plug makes UNDERgassed guns run better.

 

Now I have some engineering in my background, & my Pops IS an engineer & machinist.

We look at the pictures of your plug & fail to see how the plug could ADD gas to the system or increase gas efficiency.

 

So,

It is JUST to tame OVERgassed guns, right?

 

If I am incorrect, please explain the physics behind it helping UNDERgassed guns.

Thanks.

Paul

Edited March 18, 2010 by Paulyski

[Cobra 76 two 2,677]

Nope. Wrong answer.

 

[Paulyski 2,227]

Nope. Wrong answer.

What's the wrong answer?

 

That it helps undergassed guns?

 

I've studied the design & can't see how it in any way magically ADDS gas pressure.

[merc545 0]

Nope. Wrong answer.

What's the wrong answer?

 

That it helps undergassed guns?

 

I've studied the design & can't see how it in any way magically ADDS gas pressure.

 

It doesn't "add" gas pressure. It just lets more gas into the gas tube than the "2" setting on the factory gas plug. I'm still waiting anxiously for my S-12 to arrive (and I have yet to see the factory plug), but I'm holding one of the Gunfixr plugs that I got from CSS. The cutout on the "3" setting is MASSIVE. So if you're running low brass, it would simply allow more gas to hit the puck than the factory plug would allow. It just makes the gas system more FAL-ish. Which is good

[Paulyski 2,227]

Nope. Wrong answer.

What's the wrong answer?

 

That it helps undergassed guns?

 

I've studied the design & can't see how it in any way magically ADDS gas pressure.

 

It doesn't "add" gas pressure. It just lets more gas into the gas tube than the "2" setting on the factory gas plug. I'm still waiting anxiously for my S-12 to arrive (and I have yet to see the factory plug), but I'm holding one of the Gunfixr plugs that I got from CSS. The cutout on the "3" setting is MASSIVE. So if you're running low brass, it would simply allow more gas to hit the puck than the factory plug would allow. It just makes the gas system more FAL-ish. Which is good

The factory plug is ground at a 45 degree angle for the low brass setting.

There is no cutout, because there is NO metal covering the ports to begin with. Just an angle above them.

It would not be possible for the cutout to let MORE gas into the system.

 

I assume there is a reason that the man himself has failed to answer my question.

Edited March 18, 2010 by Paulyski

[Mullet Man 2,114]

The factory plug is cut/shaved at an angle all the way across the diameter of the plug on setting #2. It should allow a healthy amount of gas thru.

I could see the GFGP directing and funneling the gases better (on 3) then the OE plug, possibly aiding in undergassed guns but at the same time possibly hindering them too by lessening the volume of gas over the period of time it has to funnel it.

 

I'm sure i'm talking out of my ass, i feel as if i am on the righ path....maybe.

 

EDIT; Paulyski beat me too it.

Edited March 18, 2010 by Mullet Man

[merc545 0]

Nope. Wrong answer.

What's the wrong answer?

 

That it helps undergassed guns?

 

I've studied the design & can't see how it in any way magically ADDS gas pressure.

 

It doesn't "add" gas pressure. It just lets more gas into the gas tube than the "2" setting on the factory gas plug. I'm still waiting anxiously for my S-12 to arrive (and I have yet to see the factory plug), but I'm holding one of the Gunfixr plugs that I got from CSS. The cutout on the "3" setting is MASSIVE. So if you're running low brass, it would simply allow more gas to hit the puck than the factory plug would allow. It just makes the gas system more FAL-ish. Which is good

The factory plug is ground at a 45 degree angle for the low brass setting.

There is no cutout, because there is NO metal covering the ports to begin with. Just an angle above them.

It would not be possible for the cutout to let MORE gas into the system.

 

I assume there is a reason that the man himself has failed to answer my question.

 

Gotchya. Well as I said, I haven't seen the rear of the factory plug yet, I just figured that the "3" cutout on the Gunfixr plug was larger than the "2" on the factory one.

[Paulyski 2,227]

I just hope the failure to respond isn't due to a desire to capitalize on the fact that many of these guns are undergassed & people, out of desperation are buying anything they can in hopes that they will fix the product without enlarging the ports or doing other fixes.

 

I mean "Gun Fixer" does sound promising....

[Racer 27 37]

Nope. Wrong answer.

What's the wrong answer?

 

That it helps undergassed guns?

 

I've studied the design & can't see how it in any way magically ADDS gas pressure.

 

It doesn't "add" gas pressure. It just lets more gas into the gas tube than the "2" setting on the factory gas plug. I'm still waiting anxiously for my S-12 to arrive (and I have yet to see the factory plug), but I'm holding one of the Gunfixr plugs that I got from CSS. The cutout on the "3" setting is MASSIVE. So if you're running low brass, it would simply allow more gas to hit the puck than the factory plug would allow. It just makes the gas system more FAL-ish. Which is good

The factory plug is ground at a 45 degree angle for the low brass setting.

There is no cutout, because there is NO metal covering the ports to begin with. Just an angle above them.

It would not be possible for the cutout to let MORE gas into the system.

 

I assume there is a reason that the man himself has failed to answer my question.

 

Gotchya. Well as I said, I haven't seen the rear of the factory plug yet, I just figured that the "3" cutout on the Gunfixr plug was larger than the "2" on the factory one.

 

No its not. ^

 

The biggest advantage that I see (because mine isn't over gassed) is the finger adjustments.

[Racer 27 37]

I just hope the failure to respond isn't due to a desire to capitalize on the fact that many of these guns are undergassed & people, out of desperation are buying anything they can in hopes that they will fix the product without enlarging the ports or doing other fixes.

 

I mean "Gun Fixer" does sound promising....

 

Could it just mean that he went to bed? Its been an hour and 13 since he first made this thread and its kind of late.

[IronRonin 19]

Hi.

 

My gun runs flawlessly with the factory plug, running Wally Federal Bulk 100% on setting 2.

 

With the gunfixr plug, it will FTE Federal Bulk on setting 3 99% of the time.

 

Thus for me, the factory puck generates more gas on 2.

 

I love the GFP, but only for high brass obviously in my specific case.

Edited March 18, 2010 by IronRonin

[Spartacus 1,619]

Okay, so while you're here...

 

Honestly... We have a bunch of guys that (weather they own one or not) seem to think that your plug makes UNDERgassed guns run better.

 

Now I have some engineering in my background, & my Pops IS an engineer & machinist.

We look at the pictures of your plug & fail to see how the plug could ADD gas to the system or increase gas efficiency.

 

So,

It is JUST to tame OVERgassed guns, right?

 

If I am incorrect, please explain the physics behind it helping UNDERgassed guns.

Thanks.

Paul

 

 

Paul,

 

There is no doubt the Gunfixr Plug (GFP) acts as a valve as it does regulate the flow of the gas. My Dad was also an engineer, and he spent a lot of time working on the valve designs for railroad tank cars. He said small changes in valve design could often make for large changes in flow performance. Different valves were often required depending on what product was being carried in the tank car. Loading/unloading rail cars takes time, time is money.

 

But there may be more to the GFP than it just being a valve. It has shaped gas channels.

 

I'm not well versed in fluid dynamics, but my layman's knowledge would lead me to believe that the GFP may in fact make a difference (vs. the stock plug) in the gas flow and overall performance of the gas system. Although the GFP can't increase the amount of gas entering the system above the maximum that the stock plug could, it's gas flow channels can affect the pressure/velocity and it may provide for a jetting effect of the gas flow.

 

There may be effects involved such as the De Laval nozzle or venturi effects.

 

http://en.wikipedia.org/wiki/De_Laval_nozzle

 

http://en.wikipedia.org/wiki/Venturi_effect

 

Some people have reported better performance with the GFP, these effects could explain that.

 

Stepping back from armchair physics for now...

 

There are other tangible reasons to use the GFP over the stock plug:

 

Better range of adjustment, more settings between minimum and maximum.

Finger adjustable.

 

Those features alone make it a worthwhile upgrade in my book.

 

 

Hi.

 

My gun runs flawlessly with the factory plug, running Wally Federal Bulk 100% on setting 2.

 

With the gunfixr plug, it will FTE Federal Bulk on setting 3 99% of the time.

 

Thus for me, the factory puck generates more gas on 2.

 

I love the GFP, but only for high brass obviously in my specific case.

 

There have been a few reports I've seen where this has happened. The explanation that I have seen is that the threading of the gas block is off and it puts the GFP in the wrong position. For those guns it may be better to stay with the stock plug.

 

Edit: As Cobra said, the plug is indexed by the detent, not by the threading. The threading would affect what position the plug is in when it bottoms out, but that''s not really important. If the ports are blocked by the GFP, back it out another turn.

Edited March 20, 2010 by Spartacus

[gpqueen 545]

Exactly what he said. It channels the gas more effiecently directly to the puc which makes it cycle low brass ammo better. These guns are designed for Buck Shot and Slugs and need a little help to run cheap birdshot. That is what this does and it allows you to change between 4 settings without a tool.

If your gun has bad porting from the factory, only CGW can help with you that.

[Cobra 76 two 2,677]

Took me about 2 minutes to look in his business section and find this:

 

http://forum.saiga-1...showtopic=26119

 

 

An excerpt from Gunfixr's original Finger Adjustable Gas Knob intro thread.....

 

"The new gas plug was built to achieve three things: first, it was to be adjustable without tools. Second, the end facing the gas piston, or "puck", was designed to better channel the gases and more efficiently utilize them, bringing them to bear on the center of the piston, so as to push straight back. To this end, the facing end has a counterbore in it as opposed to a centered stud, like the original does. Third, it was to give a setting in between the 2 original settings, as when firing 2 3/4 inch slug loads and high brass heavy game loads seem a bit punishing to the gun and shooter. While it has been established that this won't necessarily hurt the gun itself, why batter it any more than necessary.

I didn't set up a target or do any patterning, as I didn't have much time and this was a function test. I didn't get to fire a significant number of rounds, so I just noted ejection and used that as the criteria for smartness of action.

For purposes of this description, setting 1 is the smallest amount of gas, the same as the original plug. Setting 2 is the in between setting, and setting 3 is the most gassed setting, as in setting 2 on the original.

For setting 1, I fired a 5 round box of the Remington 3 inch mag shells through without a hitch. A noteable muzzle flash was evident, and the action was cycled solidly, with the shells kicking out about 8-10 feet away. Of the Federal 3 inch shells, only 3 were fired. Of these, 2 failed to eject, with the bolt being stopped having the open end of the shell stuck on the end of the chamber. Setting 1 would appear to need a little more opening up. I purposefully made it small just for this.

For setting 2, the high brass heavy game loads fired without incident, having fired 5-10 shells, they ejected about 8-10 feet away. The low brass standard game loads also cycled the action well, kicking the hulls about 6-8 feet away. The low brass general purpose shells did cycle, but just "dribbled" the hulls out of the action.

For setting 3, the low brass standard game loads cycled the action smartly, kicking the shells approx. 8 feet away evenly. The general purpose low brass shells, the "Walmart specials", cycled the action smartly as well, kicking the hulls about 6-8 feet away.

 

As far as achieving my goals, the knob is adjustable by hand. It does also give better results with the very weak shells. Once final tweaking is done with setting 1, it will work the 3 inch shells with just enough gas, but without a lot more, which it may have done already, but this was not the specific reason for this project. I plan to actually reduce the second setting some, as it is really for the heavy 2 3/4 inch shells. It won't work with the weak 2 3/4 inch shells, but will be easier on both the gun and shooter with heavy 2 3/4 inch shot loads and slugs. This, and no tools adjustment, are the main goals."

 

 

 

Review:

 

http://forum.saiga-12.com/index.php?showtopic=27819

 

[Paulyski 2,227]

 

I fully aknowledge the advantage of hand adjustment (if the threads aren't yet caked with powder / wadding & impossible to turn by hand which I assume is why the slots are still on the plug so one can use a tool if needed) & the wider range of settings.

I would be interested in pressure comparisons between the two.

Upon looking at the shape of the channel, it occurred to me that the fact that it was much more enclosed than the factory plug led me to the question of weather or not the channel would actually slow the gas as it entered the system, thus decreasing pressure. Also I was wondering what differing dynamics of the enclosed space around the ports would contribute, weather it would create a vortex above the ports. Of course this is theory, as I don't have access to a plug & it would be rather involved to conduct a pressure test, being as the gas tube & push rod would need to be off the gun to actually test.

If there was indeed more force (pressure) at the center, one would think it would register on a meter. At any rate, It would be nominal, as overall pressure is the driving force of the piston.

Some may notice that a gun on the border of being under-gassed will not cycle as reliably at first when the gun is clean & cold, because the debris actually seals the system (puck & threads) and increases pressure & a lack of this seal lets small amounts of gas leak, leading to the need for the under-gassed gun to "warm up" before cycling regularly. (a fact that Waffenschmied was eluding to in a previous discussion when he was attempting to get another member who was having issues to test his gun & truthfully report back the results) I noticed what he was testing, as I have experienced this myself.

As for positioning of the gunfixrs channel impeding performance due to factory threading inconsistencies, that part didn't even occur to me, as I was going off of the "all or nothing" aspect of the factory plug's settings.

 

Subjective claims can be influenced by psychological entrapment, so one should be certain of improvement before endorsement. I.E. people don't want to feel like fools, so they will continue down the wrong path simply because of their current investment despite indicators pointing in other directions.

 

Something that came to mind as I was pondering the concept & usefulness of this plug (especially if the most open setting does indeed decrease pressure) was to use it so one could intentionally & heavily over-gas their gun.

I don't just mean make the ports over-sized, I'm saying, shorten the gas system like on an SBS (but retain the 19" barrel length) AND drill over-sized ports to attempt to make the LIGHTEST loads such as bean bags & pepper balls cycle in a semi auto fashion, but still be able to tune it down so one can fire still fire 3" magnum without damaging the gun. Reduced springs may also have to be employed for the LIGHTEST non-lethal rounds. (if one could make them work dependably at all)

This is just a concept that came to mind some time ago when I first took interest in the plug. Unfortunately I'm not currently in the position to experiment with this, as I currently lack a lathe to turn down the barrel, & any investment gun that I do at the time must sell as quick as possible as I don't have the extra capitol to throw around at the moment.

I think LE & others would get a kick out of the non-lethal option if it could be done this way.

 

Just some ideas.

 

But I guess my question is answered as to the makers theory of operation for the gunfixrs plug helping under-gassed guns is officially that it blows lower on the piston. (albeit not actually increasing pressure in the system)

However the individual results experienced may vary due to thread starting inconsistencies from Izhmesh.

Thanks.

Paul.

[elia.jon1 1]

hell i thought you just left it on 1 all the time?

 

 

 

 

....edited to say.....

 

i thought the russians designed the saiga 12 to work with any kind of shotshells in any order in any length(within chamber specs) mixxed in the magazine and everything.....

Edited March 18, 2010 by elia.jon1

[elia.jon1 1]

But I guess my question is answered as to the makers theory of operation for the gunfixrs plug helping under-gassed guns is officially that it blows lower on the piston.

 

 

didn't it say it hits it in the center....it seems the factory on 2 is about as low as you can get the gas on the puck.....and on setting 1, straight up into a 45 would put it lower on the puck than a pill shape cutout...

[John_pro2a 3]

I just hope the failure to respond isn't due to a desire to capitalize on the fact that many of these guns are undergassed & people, out of desperation are buying anything they can in hopes that they will fix the product without enlarging the ports or doing other fixes.

 

I mean "Gun Fixer" does sound promising....

Nate is a stand up guy, and I can't envision him trying to "capitalize" on someone who is desperate.

 

He's answered the questions in his own sub-forum.

 

It's not his 'job' to explain everything about how his design works, it's his own R&D, you're free to do your own R&D.

 

Here's an idea: buy a gunfixr plug from CarolinaSS and try it in YOUR gun. If it helps, keep it, if it doesn't help then return it to CSS (I believe they would allow that, check with them first).

 

*disclaimer* I am not a gunfixr or CSS employee, I recieved no compensation for this post

Edited March 18, 2010 by John_pro2a

[Paulyski 2,227]

Nate is a stand up guy, and I can't envision him trying to "capitalize" on someone who is desperate.

 

He's answered the questions in his own sub-forum.

I have no idea who "Nate" is.

If he is Gunfxr, if you notice, he leaves NO indacation of what the name of his business is in his sig line like other business members do.

I didn't know that he actually had his own sub-forum here, or I would have asked him sooner. I have wondered n the past if he had business member status simply from a connection to another business member.

 

It's not his 'job' to explain everything about how his design works, it's his own R&D, you're free to do your own R&D.

If someone makes claims, one would think they would defend those claims when asked.

 

You see, before I read Cobra's post, I thought everyone was just talking out of their asses & just guessing about the plug helping undergassed guns. I figured dude would respond quickly (note I posted my question 7 minuets after he posted his topic) with the answer that some simply jumped to the wrong conclusion.

Cobra's post alerted me to the fact that he had a business section & that he did indeed say it improves the function of under-gassed guns.

I really wasn't trying to raise a BS flag on the guy.

I left for work in my hospital @ 22:30 PST though & didn't see the posts until I got home.

 

Here's an idea: buy a gunfixr plug from CarolinaSS and try it in YOUR gun. If it helps, keep it, if it doesn't help then return it to CSS (I believe they would allow that, check with them first).

The only problem with that is I actually know the theory of operation of the guns & have already turned my Vodka Special into a fire-breathing ammo hungry beast that eats everything that I put through it aside from bean bags.

 

All my internals are polished, my gas system is spot on, & my gun is VERY dependable.

Mine works great with the factory plug & I can run the most powerful, down to the shittiest winchester value pack through my MD-20 without changing anything but the gas setting. (shit, I don't even NEED to change that if I'm okay with beating the shit out of my gun)

The only issue I have had is beating down the disconnecter from excessive use.

 

My gun would need to be malfunctioning to do your test.

As for my sale guns, I make them to run just like mine, so they run great with all the factory springs & plug, so doing an extensive test on something I don't need would be kinda futile.

 

Now in the future, I hope to test the overgassing & compensating experiment for non-lethal rounds on a gun I buy specifically for that project. THAT would be the time to do your test, if I'm lucky enough to get a vodka special for the test. Until then, I need to focus on spending money to make money.

 

Sorry for any confusion.

Paul

Edited March 18, 2010 by Paulyski

[GuyFoX 24]

Due to issues between Mike Davidson and myself, MD Arms will no longer be producing the Gunfixr Gas Plugs.

 

Greg at Carolina SS is now producing them, and they are available from him.

 

I wish Mike Davidson all the best in any future endeavors he may pursue.

 

Oh, hmm, I wasn't expecting this; I'm tempted to speculate on what provoked this split but I'll refrain. I suppose this is why I have not received a response from MD Arms about wanting to add Gunfixr's Gas Plug to my drum pre-order? On MD's site it says that the next run of GF's Plugs would be ready before the drums, but I guess that won't be happening? Or will MD Arms be getting one last run of your plugs??

 

 

As far as the speculation about the plug design and how it channels the gas, I'm just wondering how the different versions of GF's Gas Plug operate differently? A few months ago I scoured the boards researching this plug, and I came across som posts(I believe by Gunfixr, though I don't remember the details and don't have a link) that talked about the design of the Gas Plug changing to improve things like the gas channels. It made me curious how much difference these changes made, and if the plugs were marked in any way to designate which version they were, or if Gunfixr has provided any information about how to tell the difference between earlier and current versions of the plug. Also curious if there will be any more changes to the design of the plug, or if it will stay the same and all of the R&D will go into his self-adjusting plug?

 

I would like to get a plug mainly for the ability to adjust it without tools, as my gun like most S12s is not overgassed and after breaking it in I doubt I will shoot much high-brass. I've read that the plug is primarily used for more/finer adjustments with high-brass loads.

Though I have read that Mike D is working on a modified Piston(I think?) for the S12 that will allow more gas through which will be great for all of the undergassed guns(and 1 more US part for 922r). I was thinking that it would be nice and give me more options(might even be able to cycle the less-lethal rounds?) to get that piston(when it's available, if he still intends to produce it?) AND Gunfixr's Gas plug. That combination would probably make my gun a little overgassed which would be easily controllable/tamed with GF's plug. I like options!

Edited March 19, 2010 by GuyFoX

[porschechris 0]

Nate is a stand up guy, and I can't envision him trying to "capitalize" on someone who is desperate.

 

He's answered the questions in his own sub-forum.

I have no idea who "Nate" is.

If he is Gunfxr, if you notice, he leaves NO indacation of what the name of his business is in his sig line like other business members do.

I didn't know that he actually had his own sub-forum here, or I would have asked him sooner. I have wondered n the past if he had business member status simply from a connection to another business member.

 

It's not his 'job' to explain everything about how his design works, it's his own R&D, you're free to do your own R&D.

If someone makes claims, one would think they would defend those claims when asked.

 

You see, before I read Cobra's post, I thought everyone was just talking out of their asses & just guessing about the plug helping undergassed guns. I figured dude would respond quickly (note I posted my question 7 minuets after he posted his topic) with the answer that some simply jumped to the wrong conclusion.

Cobra's post alerted me to the fact that he had a business section & that he did indeed say it improves the function of under-gassed guns.

I really wasn't trying to raise a BS flag on the guy.

I left for work in my hospital @ 22:30 PST though & didn't see the posts until I got home.

 

Here's an idea: buy a gunfixr plug from CarolinaSS and try it in YOUR gun. If it helps, keep it, if it doesn't help then return it to CSS (I believe they would allow that, check with them first).

The only problem with that is I actually know the theory of operation of the guns & have already turned my Vodka Special into a fire-breathing ammo hungry beast that eats everything that I put through it aside from bean bags.

 

All my internals are polished, my gas system is spot on, & my gun is VERY dependable.

Mine works great with the factory plug & I can run the most powerful, down to the shittiest winchester value pack through my MD-20 without changing anything but the gas setting. (shit, I don't even NEED to change that if I'm okay with beating the shit out of my gun)

The only issue I have had is beating down the disconnecter from excessive use.

 

My gun would need to be malfunctioning to do your test.

As for my sale guns, I make them to run just like mine, so they run great with all the factory springs & plug, so doing an extensive test on something I don't need would be kinda futile.

 

Now in the future, I hope to test the overgassing & compensating experiment for non-lethal rounds on a gun I buy specifically for that project. THAT would be the time to do your test, if I'm lucky enough to get a vodka special for the test. Until then, I need to focus on spending money to make money.

 

Sorry for any confusion.

Paul

I also find it hard to believe that the "gas flow" is being directed more squarely on the gas piston with the GFP.

 

"Gas Flow" out of three or four poorly drilled Russian ports would hardly create uniform flow. Flow would be extremely turbulent.

 

About the most you could expect is to limit flow and therefore peak pressure that is seen at the face of the puck.

 

I have 3 correct sized gas ports. My saiga functions better with the stock plug on "2". Lots of FTE's on GFP #3.

[Stansplace 414]

Paulski is pretty much dead on with what he said above. I'll add:

 

Ayep, pretty much agree with all of the above. I could never figure this one out either. When I got my first S12, I was reading the forum and the net and almost fell for this one to. Don't get me wrong, if you can't just pop your stock plug into the mill and cut what you need off with a ball end mill and/or want to be able to adjust without a stick or some shit, then this may be for you. I did contemplate doing this mod to my stock plug, but elected to polish, tweak, run, and drill out my gas ports first. (Cobra, you rock by the way) He gave me a little assist with the gas block removal. I am a little lazy from time to time.

 

Anyway, after working on my internals by polishing (dremel tool and a little lapping compound) and recontouring the carrier/bolt assembly, I had no need. My gun is now pretty much beyond reliable. I have had exactly 0 failures of any kind since doing this work. (1500 rounds or so) I will admit that by looking at the GFP, it may channel the gas a little better. Is it necessary, not if you don't mind doing a little work on your gun. The one point I would like to make about this entire thread and the entire concept of low brass cycling in these guns is: THIS GUN IS A WEAPON AND CYCLING BIRDSHOT IS JUST FOR SHITS AND GIGGLES. THIS GUN WORKS FINE OUT OF THE BOX FOR WHAT IT WAS DESIGNED TO DO. I.E. SHOOT REALLY DANGEROUS SHIT OUT OF THE LOUD END OF THE BARREL. That is unless you have a legitimate vodka special which requires warranty work. Then the GFP WILL NOT HELP YOU. To those of you without a ball endmill and a milling machine, go ahead and spend the reasonable 35 dollars on one. I don't really care and if your gas block, gas ports, threads happen to fall in a certain location on this poor tolerance AK platform, then the plug is for you. If not...........

Edited March 19, 2010 by Stansplace

[Gunfixr 76]

Good grief. All I did was to say that gas plugs of my design would no longer be available from MD Arms, and that they would be available from Carolina SS.

Like many business members here, I have a lot of things going on. Right after I posted the OP, I logged off, and went on to the next thing. If that upset somebody, well I'm sorry, but I had many things to do before I could go to bed for the night.

First off, the plug will not give more gas to the piston than the ports let through, and it was not designed to do that. At the time, "vodka specials" didn't even exist, they hadn't showed up yet. The biggest complaints about the gas system were that competitors couldn't change from 1 to 2 to use slugs and then birdshot at matches, and the system fouled up real bad. Some guns also had trouble with bulk pack low brass ammo.

My plug was to be hand adjustable.

The end is cut very differently, and for several reasons. One, the end diameter, where it meets the puck, was increased all the way to puck diameter. This was done so that as the gases passed by the plug to the puck, they were limited in how much could flow around the end of the plug, and specifically, back to the threads. This was to keep the threads and the groove between the threads and the puck chamber cleaner. At the time, in order to clean out the gas block, the groove at the back of the threads had to be scraped out to get the puck out. The old timers here will remember this.

Second, the end has a counterbore instead of a stud on the center. This also serves two purposes. One, as this space between the puck and the end of the plug fills with gases, this keeps them more centered against the plug, instead of out around the edges. Two, whenever you have a cylinder sliding back and forth in a close fitting bore, any tilting of the cylinder will bind it in the bore. To that end, the leading edge of the plug is around the edge, so that as the puck is slapped up against it by the bolt carrier, it will come to rest square and true to the bore.

Third, the gas channels are cut as slots. This had to be done in order to have more settings. The factory plug never really blocks off the hole in the gas block, no matter where it's set. You will always have a setting of 1, except when it's on 2. This is because of the smaller diameter of the end, the highest point of the end being in the center of the part, and the length, which determines how far over the gas block hole it covers. My gas plug is longer than the factory one, and when fully seated, will fully block the gas block hole in most guns. My original hand made plugs had a "0" setting, wherein the gun wouldn't function. A few would barely cycle with 3" magnum loads, most would not. So, on setting 1, the gas block hole is barely visible. On setting 2, more of it is visible. Setting 3 has a channel cut slightly larger than the gas block hole, meaning that the entire hole is open to the puck. While there will be turbulence in the gases, they are directly channeled to the puck, close to the center. When the gases hit the bevel on the factory plug, they will spread out, both toward the puck, and to the sides, which is not toward the puck. The grooves insure that almost all of the gases go directly to the puck.

 

Is it perfect? No, I dreamed it up a few hours. It took far longer to test them and tweak it than it did to come up with the idea. The specifics of the tolerances were loosened up a bit for mass production. My hand made batches were much tighter. This has undoubtedly negatively affected it performance. Also, the guns themselves have changed since I first designed it. They are sloppier now also.

 

Will it make up for an undergassed gun? Sometimes, yes, it will. Why? Back to the part about being longer inside the gas block than the factory one. I also experiment occaisionally with pucks, and the plugs, changing something just to see what will happen. Part of what makes the gun work is the combination of the amount of gases, combined with the space they are put into. The longer plug, which is also larger on the end, reduces the gas expansion space between the plug and the puck. So, if you take the same gun, and fire it with the factory plug, and fire it with this plug, you will get slightly different pressures in the gas block, because the same amount of gases are being put into a slightly smaller space.

I did make a puck, and bore a big counterbore into it. It made the gun not work, go back to regular puck, gun works. Put a big counterbore into a plug, and the same thing happened. Same amount of gas, larger space, less pressure.

 

It won't fix every gun, and I never said it did. They didn't get stuck very often in the beginning, but smaller sizes for mass production, and sloppier guns means sometimes they do, so the tool slots were added. Even so, just slapping something in the slots and giving a twist is still easier than pushing down the locking pin while twisting on the plug.

 

Hopefully, this satisfies you question. I had to work today, like most days, so I don't get on here until nightime.

 

Oh, and "ball end mill" thing? Well, it's much easier to clean out a radiused cut full of crud than than digging it out of the sharp corners.

[Crusader 64]

Due to issues between Mike Davidson and myself, MD Arms will no longer be producing the Gunfixr Gas Plugs.

 

Greg at Carolina SS is now producing them, and they are available from him.

 

I wish Mike Davidson all the best in any future endeavors he may pursue.

 

 

 

 

 

 

 

Issues? Is there anything I could do to smooth things over? Do you need me to mediate a dispute between you and Mike? Maybe I should have intervened sooner.

Edited March 19, 2010 by Crusader

[Paulyski 2,227]

Thank you for your response.

 

Edit:

Directed to Gunfixr, not crusader.

Edited March 19, 2010 by Paulyski

[Crusader 64]

Thank you for your response.

 

Edit:

Directed to Gunfixr, not crusader.

OK, I will try to be more constructive. I find the GUNFIXER plug both allows my Saiga to cycle lighter loads as well as reduce the gas on magnum loads to prevent wear on the reciever. Once you figure out which setting to use for each load, you are good to go. I consider this plug a required part for all Saigas. There should even be a law requiring all saiga 12s to use GUNFIXER plugs.

[Paulyski 2,227]

Thank you for your response.

 

Edit:

Directed to Gunfixr, not crusader.

OK, I will try to be more constructive. I find the GUNFIXER plug both allows my Saiga to cycle lighter loads as well as reduce the gas on magnum loads to prevent wear on the reciever. Once you figure out which setting to use for each load, you are good to go. I consider this plug a required part for all Saigas. There should even be a law requiring all saiga 12s to use GUNFIXER plugs.

Gunfixr has responded with a rationale.

I have some solid ideas on why some members have experienced issues, but for the time being I am going to accept the rationale presented as I have not tested it & discuss this no further on this thread.

For the record, I like the idea of the plug & it is ONLY the low brass claims that I was inquiring of.

Thank you for being constructive Crusader.

[IronRonin 19]

Thank you for your response.

 

Edit:

Directed to Gunfixr, not crusader.

OK, I will try to be more constructive. I find the GUNFIXER plug both allows my Saiga to cycle lighter loads as well as reduce the gas on magnum loads to prevent wear on the reciever. Once you figure out which setting to use for each load, you are good to go. I consider this plug a required part for all Saigas. There should even be a law requiring all saiga 12s to use GUNFIXER plugs.

 

Except for cases like me where it has LESS gas on 3 then factory plug on 2.

 

Federal bulk smartly kicks out 100% for me on Factory 2; 99% FTE with GFP on 3.

 

Just reiterating to prove a point...if you have weird threading in your gun (not uncommon) things might not line up right.

[Cobra 76 two 2,677]

Threading shouldn't make much difference really. The plug is indexed by the detent pin. If it's locked into a notch, the vent hole of the plug is lined up pointing down, where the ports are. If anything you may need to unscrew it one more turn.