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How do you time the Barrel and Bolt?


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My Saiga 12 has a considerable "bump" when going into battery right before the bolt rotates to lock up. I would like to know how to remove this. At first i thought it was the extractor ramping up on the barrel but looked at it and the timing was off slightly from when the extractor rode up and where the hitch/bump was. The weird thing was thought that I took the extractor spring out and the bump went away. Maybe the spring pressure on the bolt/barrel was creating tension somewhere else???? I started reading on here that there might be a timing issue on the angled area on the barrel extension part where it hits the bolt and makes it rotate into lock-up. How do you time this area? What are you looking for proper timing and how do you know if you haven't removed enough, have removed the right amount or have removed too much material???

 

Thanks

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My Saiga 12 has a considerable "bump" when going into battery right before the bolt rotates to lock up. I would like to know how to remove this. At first i thought it was the extractor ramping up on the barrel but looked at it and the timing was off slightly from when the extractor rode up and where the hitch/bump was. The weird thing was thought that I took the extractor spring out and the bump went away. Maybe the spring pressure on the bolt/barrel was creating tension somewhere else???? I started reading on here that there might be a timing issue on the angled area on the barrel extension part where it hits the bolt and makes it rotate into lock-up. How do you time this area? What are you looking for proper timing and how do you know if you haven't removed enough, have removed the right amount or have removed too much material???

 

Thanks

If the "bump" went away when you removed the extractor spring, the extractor spring is the cause of the "bump".

Not sure if I misunderstood your post though.

 

When I tune extractors I add my own spring which virtually eliminates that without compromising reliability & I include the factory spring back with the parts for the off chance that that client wants to go back.

I had the springs made for longer life & so consistancy is ensured rather than cutting on & streaching out the tri-braided.

 

I'd reccommend one doesn't mess with the timing unless they know darn well what they're doing.

 

How many rounds have you fired through the weapon?

Reason I ask is the steel of these parts of the gun is designed to self work harden. That means it beats it's self down in a few places (the top of the barrel hood being a perfect example) & when it's beaten down, the steel is harder in those working areas while at the same time other areas stay softer, thus less likely to fracture.

This is the part of the break in that's unavoidable. The guns loosen up a bit when the parts that are supposed to get beaten down do so.

 

If a person goes messing with the timing before it's beaten the working areas down, the gun will continue to beat the new area down & you'll be out of time.

 

If you mess up the heat treating there, you're talking a 1500 degree heat treatment to get it back to where it should be, so I would recommend against that also.

 

Timing though, that can be very dangerous if you mess up, so i would strongly reccommend against anyone who has to ask doing it themselves.

Send the gun to someone like Jack Travers of JT Engineering if you want the gun timed & don't know how to do it.

You can't go wrong that way.

 

However, if you mess up the way the lugs lock up, you could very easily eventually end up with a carrier embedded in your forehead.

 

Bad news.

 

I don't want to be a Debbi-downer, but the timing is seriously the last place someone who doesn't know what they're doing wants to mess with.

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My Saiga 12 has a considerable "bump" when going into battery right before the bolt rotates to lock up. I would like to know how to remove this. At first i thought it was the extractor ramping up on the barrel but looked at it and the timing was off slightly from when the extractor rode up and where the hitch/bump was. The weird thing was thought that I took the extractor spring out and the bump went away. Maybe the spring pressure on the bolt/barrel was creating tension somewhere else???? I started reading on here that there might be a timing issue on the angled area on the barrel extension part where it hits the bolt and makes it rotate into lock-up. How do you time this area? What are you looking for proper timing and how do you know if you haven't removed enough, have removed the right amount or have removed too much material???

 

Thanks

The question I would ask you, are you have any issues with the gun? If your not I would not mess with anything. I'm like you and want everything perfect but if you start messing around with the timing your could end up screwing things up real bad. Good luck with whatever you do.

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Paluly can you elaborate on the carrier to the forehead thing? How does it occur? Why? That is a scarry thought!

Hacking on lug embuttments or messing up the timing to the point that the gun beats it's self to shit & wears the embuttments drastically so the gun doesn't lock up right.

 

I'm not saying don't time the guns, just that a person who knows exactly how everything interacts & effects everything else really should do it.

 

I just got done re-threading the female part of a carrier where the op-rod screws in because a gentlman cut the factory op-rod off, then drilled down the center of the rest of the op-rod that remained in the carrier with the intention of taping it for a Tom Cole HD Op-rod.

 

Nothing people do can really suprise me.

When talking about something as important as a gun locking up correctly I just figure that may be one thing a person may want someone who's been doing it for a while to do or supervise while they do it.

 

On most stuff screwing up some thing may mean a broken part that's really difficult to replace, but screwing up how a gun that one shoots magnum slugs out of locks up may be a little more problematic.

 

I don't know what skillsets anyone who may read this thread down the road has.

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OP,

The extractor contacts the slot at almost the same time that the top lug on the bolt contacts the barrel hood and initiates the rotation of the bolt. When you removed the extractor spring, you removed the only significant source of resistance to the bolt going forward enough to engage the timing surface of the hood and rotate into the lockup channels.

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