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350oshin

how do i polish the bolt?

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Well having wood like you do is a great start. Basically just pick a hand, apply lube and go to work, even strokes, slow yet firm. You can increase speed as you need based on how close you are to climax/completion. One important thing to consider and this is important because a lot of people tend to do this, (more than you would think) do not by any means neglect the nuts while polishing the bolt. You will be amazed at how fast this brings the task to completion. Hope this helps and good luck. Oh and uh...pics or it didn't happen.

 

 

Super A obiously has done his homework and know what he is talkig about....

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The video of the bolt closing the last 1/2 inch is awesome....and while I've polished my feed ramp, rails, bolt, carrier, hammer and so forth, and while my gun is as smooth as silk....it still hesitates at this precise point in the closing. I note that the bolt rotates at that point, and looking very closely, it appears the bolt is camming over a boss in the bolt carrier. That boss has sharp corners/edges, and looks as if it too could be smoothed a bit with careful polishing. However, I'm afraid of impinging upon the 'timing' issue mentioned above if I attempt to do that.

 

Is that an area where improvement can be had? Or should it be shunned like a rabid dog?

 

And by the way, the help this thread, well, shucks, the entire site, selflessly provides is immeasurable and priceless, insofar as owning and running the Saiga12 is concerned. My sincerest thanks indeed!

 

PJJ

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Edited;

 

After much testing I have found that in order to ensure the best reduction of friction from the underside of the carrier to the hammer face, polishing of the hammer face is unnecessary.

 

If one were to run a gun with an absolutely perfectly polished hammer face & a perfectly polished underside of carrier, dry, the amount of friction will actually INCREASE GREATLY from what it would be without doing anything at all.

 

The best combination I have found, is to polish & profile the bolt perfectly for easier magazine insertion & friction reduction during cycle, slightly profile the sharper transitions of the underside of the carrier & polish it smooth while taking care to not remove steel from the entire length of the carrier so the hammer resets, polish the guns rails, but use a wire brush bit down the rail guides on the carrier. And correctly profile the hammer, do smoothen it well, however I would not recommend HIGHLY POLISHING all metal to metal surfaces. For a perfect finish, IMHO, bringing the hammer face to a rough polish will provide the most versatile combination of friction reduction, regardless of if the oil wears away.

 

Yes, high polishing looks pretty, but all metal to metal mirror polishing may prove counterproductive.

 

Eventually, after firing, the pieces will wear their own grooves & make their own path.

 

 

If anybody doubts my findings, take a couple of clean glasses & try to rub them on eachother.

You will find a lot of friction. Or, just rub two perfectly polished pieces of steel against eachother.

You will find the same results.

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The video of the bolt closing the last 1/2 inch is awesome....and while I've polished my feed ramp, rails, bolt, carrier, hammer and so forth, and while my gun is as smooth as silk....it still hesitates at this precise point in the closing. I note that the bolt rotates at that point, and looking very closely, it appears the bolt is camming over a boss in the bolt carrier. That boss has sharp corners/edges, and looks as if it too could be smoothed a bit with careful polishing. However, I'm afraid of impinging upon the 'timing' issue mentioned above if I attempt to do that.

 

Is that an area where improvement can be had? Or should it be shunned like a rabid dog?

 

And by the way, the help this thread, well, shucks, the entire site, selflessly provides is immeasurable and priceless, insofar as owning and running the Saiga12 is concerned. My sincerest thanks indeed!

 

PJJ

 

"The video of the bolt closing the last 1/2 inch is awesome"

 

Most of the time the draging is acually due to the extractor spring resistance not the bolt camming or what not.

 

Just remove the extractor on a stock, unmodified bolt and try it.

 

I believe some builders use a weaker extractor spring or modify the original.

Edited by saigatechusa

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I'm not giving you flack buddy. I hope you don't think I felt disrespected. I was merely sharing my experience with my gun. I am in awe of your work by the way, you are truely skilled. Not trying to kiss ass, just stating the obvious.

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On my sets, I have tuned springs, being as the repurposed AK extractor springs are ridiculously strong, but I don't tune it down as much as some do.

 

The spring is going to wear with heavy firing. I could tune the spring WAY down or do a couple of other things to give my clients the illusion of an even smoother action than I already turn out, but it would be at the expense of long term reliability.

 

You need to know what they intend to do with the weapon. Do they just stroke it & dream, or intend to shoot once in a great while & will never truly wear the parts in by workhardening them, or do they plan on having the gun forever & shooting the hell out of it like I do & want long term durability as well as an immediate increase in reliability as well as ease of magazine insertion on a closed bolt & cycling drums better without changing drum spring settings?

 

The wearing from heavy use is actually engineered into the guns.

This can be seen in the specific steel used due to it's properties in many internal parts of the guns including those being worked with in this thread. It's strong as all hell, but not super hard (like the receiver is).

According to Izshmash reps, it's made this way, because if it were super hard it would be brittle. Therefore they designed many parts to self-workharden some areas, so the right areas are hardened and the other areas are strong as a stump for compression, but not brittle.

 

 

Most want a do everything gun. There's a fine balance to build the quarter-horse of guns.

 

They come from the Russian factory like a "Clydesdale", only wanting the most powerful ammo.

 

In America the "quarter-horse" is preferred to be able to handle both the light & the heavy, but still be durable, thus increased gas regulation developed in the US.

 

The absolute smoothest when brand new are the through-bread raceguns made to run the lightest loads, but like race horses, they're more fragile, being built right on the edge. Springs & steel still wear. Workharneding occurs & tolerances get looser as this happens. The absolute smoothest out of the box, may well be too loose if used heavily for years on end.

 

My goal is to get it to run the lightest ammo readily available, being reliable, however still have the long term durability of an AK & be able to shoot heavy loads all day long without excessive wear.

 

If the SHTF, I'd like my guns to still have a long life left. :)

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I'm not giving you flack buddy. I hope you don't think I felt disrespected. I was merely sharing my experience with my gun. I am in awe of your work by the way, you are truely skilled. Not trying to kiss ass, just stating the obvious.

 

No problem

 

I was only referring to you by your experience you posted.

 

No disrespect on either parties

 

and thank you :super:

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This thread may well be one of the most helpful on this entire forum, insofar as making a Saiga run right.

 

Each time I clean my Saiga, I remove the bolt and carrier, along with the gas plug and puck, and give them a good once over on a six inch buffing wheel. Most of the time, I also use a wire brush on the puck and gas plug.

 

In any case, the gun runs like a dream after cleaning, and will easily go through 6 to 8 hundred reloaded shells. And even then, the only sign of problems will be with short brass Winchester cheapies....One fine gun, and one fine forum in support of that gun.

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how do i smooth out the rear spring it makes kind of a grindig sound when I hand cycle it slowly. also seems like it catches a little bit just before the bolt closes all the way

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how do i smooth out the rear spring it makes kind of a grindig sound when I hand cycle it slowly. also seems like it catches a little bit just before the bolt closes all the way

It really wasn't made to be cycled slowly. Let it fly forward at it's own speed.

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it appears the bolt is camming over a boss in the bolt carrier. That boss has sharp corners/edges, and looks as if it too could be smoothed a bit with careful polishing. However, I'm afraid of impinging upon the 'timing' issue mentioned above if I attempt to do that.

 

 

Don't round those corners, they are there for a reason. This is what keeps the carrier from trying to rotate the bolt when the action is cycling, especially when stripping a round from the mag, or if the shell hangs a little going into the chamber. It is one of the little appreciated differences that makes an AK superior to an AR in austere conditions. If these get rounded from wear, it is one of the things that can cause an old AK to become tempremental. If you round those corners then any resistance met by the bolt causes the bolt and/or carrier to bind against the rails as they are then the only things to prevent the bolt from rotating. Dynamically, there is a bit of forward pressure on the camming surfaces even when the mag is empty, due to the braking/acceleration of the mainspring and the mass of the bolt.

 

 

Take the bolt and carrier in your hands. Turn the bolt to the unlocked (forward in carrier) position, so the lug surfaces align with the rail slots on the carrier. Notice that if you push the bolt hard into the carrier, it won't move rearward or turn no matter how hard you push. This is what the bit I quoted describes, and it is the corners on the bolt boss and cam slot that cause this. To get it to move back, you have to rotate the bolt just a tiny bit toward the locked position. This is by design and makes the gun operate freer especially if dirty or poorly lubed. Yes, you can still make them work without this feature, and ARs do so at least when they are clean and lubed.

 

So the carrier can't lock the bolt without the bolt already starting to lock. What allows it to work?

 

Look at the very rear of the barrel shroud, on the left side of the extractor slot. See that 45 degree angle? If you take the bolt out of the carrier and slide it forward into battery, you will find that just before the bolt is fully forward, that ramp on the shroud hits the cam follower lug on the bolt, and starts the locking rotation. That is what knocks the cam follower off that step in the cam profile, and allows the carrier to finish locking the bolt. On a standard AK, there is a ramp at the front of the left slot that hits the left locking lug and does the same thing.

 

Most of the resistance to closing is the extractor climbing up the ramp on the chamber face.

Edited by kevbo
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I spent a couple hours today trying to get a nice cosmetic mirror shine on my carrier. I used dremel abrasive wheels (wore out 3) followed by pads with the red polish, I just don't seem to be able to get the fine horizontal lines out. Perhaps I just did not go long enough with the polish step, but I ran a whole battery dead polishing. Any tips? The way I was going it seemed like I could grind my way through the whole piece without getting anywhere so I was hesitant to continue.

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I spent a couple hours today trying to get a nice cosmetic mirror shine on my carrier. I used dremel abrasive wheels (wore out 3) followed by pads with the red polish, I just don't seem to be able to get the fine horizontal lines out. Perhaps I just did not go long enough with the polish step, but I ran a whole battery dead polishing. Any tips? The way I was going it seemed like I could grind my way through the whole piece without getting anywhere so I was hesitant to continue.

Don't feel bad.

Most professionals can't get the fine marks out either. I'm often sent pieces that others have done for finishing work.

I've spent thousands of dollars & much time with top industry consultants to bring GlassBolt to the level it is.

 

Retail products & equipment just will simply never get you there.

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Pauly, you hit on a point and may have actually already answered a question I was always curious about-are parts like the bolt and carrier fully heat treated or just case hardened OR does it have more to do with the material make up of the parts. Long term use on something that was just case hardened is a bit of a concern if we're removing that by re-profiling, if it's fully heat treated it's not a big deal, and if it work hardens it's probably not a problem but to tell you the trueth I don't know. I thought at some point I had read thet the G2 FCG was case hardened which I tend to believe since I can see wear patterns on the hammer showing up shortly after adjusting it for the S12. Sounds like you've had some degree of formal training in this area so I thought I'd throw that out since I've never really seen it discussed. If any of the parts are case hardened it might make a case to use Kasenit following profile work?

http://www.brownells.com/.aspx/pid=7626/Product/KASENIT

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Mark, Pauly and I were actually discussing that exact thing on the phone yesterday, and as I told him, it is my belief (from what I was told by another well known vendor in the industry) that the G-2 is not case hardened, but is fully heat treated. Something else I was discussing with this other vendor, who BTW is quite knowledgeable and MFGs many of his own parts from steel... was the fact that as long as one is holding the workpiece in one's bare hands, he's not going to destroy the temper in the steel while working it. This has always been my policy...if it's too hot to hold without burning my skin, it's too damned hot period. Pauly and I also agreed on this.

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Anyone wants to case harden, they're better off saving their $$$ & powdering charcoal, heating to bright cherry red, cooling in the charcoal, re-heating & oil quenching.

 

However, I've seen equal wear on both untouched & previously treated disconnecters, which get the most wear out of any FCG part.

I'm fairly certain that this is why Tapco says "heat treated" rather than "case hardened"

It would be a thing to advertise if they were indeed, being as it takes more steps, so it wouldn't make sense not to specifically state it.

 

That being said, I see MASSIVE wear on the Russian hammers that I get in compaired to wear that I've ever seen on any Tapco, so this would lead me to believe that the Russians wanted a softer hammer than firing pin/bolt, being as a hammer is more easily replaced & can be deformed more without effecting cycle.

 

I'm talking full imprints of the bolt's shaft on Russian hammer's faces at times.

 

I'm sure Cobra's seen the same.

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I have personally tested a few of the G2's on a Rockwell tester. They are heat treated, but are hit and miss on their hardness. They vary quite a bit for a treated part. This could be because of the carbon content of the base metal or the way they are treating them. I haven't seen any variations that would cause serious problems such as cracking/breaking or deformation. Hope this helps, I got some strange looks testing these. (The guys knew they were FCG parts) As in WTF is he doing now? :lolol:

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I have personally tested a few of the G2's on a Rockwell tester. They are heat treated, but are hit and miss on their hardness. They vary quite a bit for a treated part. This could be because of the carbon content of the base metal or the way they are treating them. I haven't seen any variations that would cause serious problems such as cracking/breaking or deformation. Hope this helps, I got some strange looks testing these. (The guys knew they were FCG parts) As in WTF is he doing now? :lolol:

 

I don't know for sure because I don't work there, but I'm certain that the hardness variances are within company mandated tolerances. It just wouldn't make sense that they aren't.

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I went out and bought a dremel kit today and did my 12 gauge tonight. I followed the directions in this post and it made it a breeze. Thanks guys.. I will test fire it in the next week or so to see if the shotgun still works :rolleyes: I'll let you know... If it works fine I will do my 20 gauge. :super:

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If you haven't reprofiled before, it might be better to go with someone well versed in it, since these parts are made from unobtainium.

 

I have been doing them for 5 years on precision machines w/ (+-) 0.0005" tolerences.http://forum.saiga-12.com/index.php?/topic/66543-boltcarriertrigger-pack-reprofiling-polishing/

 

Cobra also does excellent work.

 

Pauly does them and does good work too.

 

If you do it yourself, read the thread and take your time, as these parts cannot be replaced.

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The video of the bolt closing the last 1/2 inch is awesome....and while I've polished my feed ramp, rails, bolt, carrier, hammer and so forth, and while my gun is as smooth as silk....it still hesitates at this precise point in the closing.

 

It is the extractor spring. Beyond polishing extractor/bbl-slot, a lot of guys shorten the spring, so the extractor goes into battery easier.

I don't shorten them unless specifically asked by customer. imho there is no real benefit...I have never seen a good running gun stop at the point the extractor touches the bbl slot. Just to much enertia when it hits.

And, I would rather keep my extractors at full power.

 

http://forum.saiga-12.com/index.php?/forum/143-cs-metall-werkes/

 

Just want to state for the record, that I was not saying adjusting the spring was incorrect. A lot of guys do it, and I can see why. I don't do it, but that is just my own opinion.

Neither is right or wrong.

Clipping it will make the extractor transition into the bbl easier, so there is some benefit.

I just choose not to do it, except at customer request, where I have no problem doing it. Just wanted to clear that up.

:smoke:

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Rather than make the customer decide on one or the other, I had my own springs made at the tuned strength to keep everything consistent & include their old extractor spring with the unit upon return for if they should ever change their minds.

 

However, the extractor spring on a factory S-12 is simply a re-puoposed AK extractor spring & it delivers too much force IMO, so I've yet to hear of anybody switching back.

For earlier units where the spring was hand tuned a person can simply put in any tribraided AK extractor spring.

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