Omega Question

[goco4game]

Several years ago, I naively bought a blued Omega .50 cal at a gun show without checking the bore. Shouldn't have done that. When I got it home, I pulled the breech plug and looked inside. The bore was so badly corroded and pitted that I almost screamed out in horror. After hours and hours of fire and hand lapping, about the BEST it would shoot is three inch groups - at 35 yards. I am presently in the process of cutting off the QLA and re-crowning the muzzle, but I'm not expecting any miracles to occur.
Recently, a used Omega barrel showed up for sale on another forum, which I purchased. It was advertised as a stripped Z5 stainless steel barrel with no action. I assumed/hoped it would fit on my standard blued Omega, and I would have a decent shooting rifle.
Should have done more research before buying it (are you seeing a pattern here?)
I learned that it actually is not SS, but regular steel with Weather Shield coating. Not a big deal to me; I would have bought it anyway.
This time, the issue is not the bore, as it's in pretty good condition. When I went to swap out the pivot block assembly, I saw that the blued model uses pins held in place with hex set screws; the Z5 uses pressed in pins, which were not included. Well, I figured that I'd either have to try to buy some somewhere or make them myself. More bother.
In the meantime, I went ahead and assembled it with the pins I had. The action worked normally and closed with a good firm "snap".
Then, I saw a problem I have not heard anyone else mention anywhere. When the pivot block rotates up and meets the rear/breech of the barrel, it's supposed to be a nice tight square fit, right? Well, with this combination, the pivot block is tight at the bottom half of the breech, but there's a gap in the upper half. When looking sideways at the breech, I can actually see light through the upper half! Obviously, this is a major issue and I never attempted to fire it. Somehow the geometry is off kilter and not allowing a nice tight lock up. I cannot see any way to make this combination work.
Has anyone else out there run into this debacle before and have a remedy for it?

 

[MSalyards]

Buy CVA!

 

[sbuff]

Were you shooting sabots or conicals ?

 

[BuckDoeHunter]

Are you able to post pictures? Have you called TC to see if the pins are available? Does the removable bushing around the firing pin look like it’s installed correctly?

 

[fishhawk2700]

There is a sticky here about adjusting an Omega action.

 

[goco4game]

Buy CVA!

I own an Optima V2. Haven't shot it a lot, but it doesn't group my conicals very well either. More experimentation is needed. However, the stock comb is definitely made to be used with a scope. With my peep sights (no scopes allowed for hunting in Colorado), I really have to scrunch my cheek down on the stock. When I called CVA to ask if they sold a stock with a lower comb, he said "no", and that I was the first person he had heard of having that problem.
If I only had a dollar for every time I've heard that one ....

 

[goco4game]

Were you shooting sabots or conicals ?

The powers that be have proclaimed sabots to be
verboten for hunting in Colorado, so they are useless to me. That being said, I did try a few PT Gold's 300 grains out of curiosity, and they shot no better. And I DO NOT do Powerbelts....

 

[sbuff]

That should rule out the qla. I'd proceed with the action sticky and start there . Just my two cents

 

[dragonfly]

The sticky explains how to tighten a loose Omega action. GoCo's post sounds like his rifle's action is out of alignment.

 

[goco4game]

Are you able to post pictures? Have you called TC to see if the pins are available? Does the removable bushing around the firing pin look like it’s installed correctly?

Since the firing pin assembly is accessed from the rear of the breech mechanism, rather than the front, like a CVA, I assume this has no bearing on this problem?

 

[BuckDoeHunter]

Mine has a screw on the rear, once removed, the bushing slides out the front, its an older Omega so maybe its different?

 

[BuckDoeHunter]

I took mine apart again to see if there was anything that stood out

Action fully closed, no gaps

Action closed but not fully locked, daylight seen towards top of breech block, I'm guessing yours resembles this but your action is fully closed

This screw pushes up against a pin and may need adjustment, does yours push up against the pin?

Maybe the nut needs adjustment, I believe this is the one in the "Tighten Loose Omega Action" sticky, the nut is circled red, the trigger spring in yellow that you don't want to release

Pin that holds the nut assembly in place, on mine, you would push on it from the other side

Does this area have a lot of slop? Or with the bolted on lug (I'm guessing it's bolted on, mine's welded), does the lug need to be moved a little for a better fit?

 

[goco4game]

I took mine apart again to see if there was anything that stood out

Action fully closed, no gaps

Action closed but not fully locked, daylight seen towards top of breech block, I'm guessing yours resembles this but your action is fully closed

This screw pushes up against a pin and may need adjustment, does yours push up against the pin?

Maybe the nut needs adjustment, I believe this is the one in the "Tighten Loose Omega Action" sticky, the nut is circled red, the trigger spring in yellow that you don't want to release

Pin that holds the nut assembly in place, on mine, you would push on it from the other side

Does this area have a lot of slop? Or with the bolted on lug (I'm guessing it's bolted on, mine's welded), does the lug need to be moved a little for a better fit?

Wow, you are really schooling me on this one. Excellent pictures. Thanks so much for all the time you're putting into this. I had no idea that the bushing comes out the front - never had it apart - I thought the breech face was all one machined piece.
After discovering the gap on the WeatherShield barrel,I removed the pivot assembly and put it back on the original blued barrel. Much to my surprise, there is a gap on this one as well! Not as bad, but the photo shows what I'm talking about. The area that is tight appears to be outside of the bushing. Tomorrow after work I will try to remove the bushing and retry the fit without it in place, as well as consider your other points. Thanks again.

 

[goco4game]

Wow, you are really schooling me on this one. Excellent pictures. Thanks so much for all the time you're putting into this. I had no idea that the bushing comes out the front - never had it apart - I thought the breech face was all one machined piece.
After discovering the gap on the WeatherShield barrel,I removed the pivot assembly and put it back on the original blued barrel. Much to my surprise, there is a gap on this one as well! Not as bad, but the photo shows what I'm talking about. The area that is tight appears to be outside of the bushing. Tomorrow after work I will try to remove the bushing and retry the fit without it in place, as well as consider your other points. Thanks again.View attachment 8840

I will attempt to answer some of the questions that have been asked. But first I want to clarify some things about the blued barrel with the badly pitted bore. I did remove the QLA, recrowned it, and shot it last weekend - no improvement in accuracy. Therefore, I am going to abandon any further efforts to salvage it, and relegate it to the status of the proverbial tomato stake. Just in time for planting season, too! It has provided me with something good to practice on. All further efforts will be directed towards trying to fit the old action on the Z7 barrel.
BuckDoeHunter: my action is the same as yours, just blued. The bushing sticks out just slightly beyond the housing, again, much like yours, maybe .010". I took it apart, scraped out some rust, and polished it with a Dremel tool and nylon brush, and reassembled.
I am familiar with the sticky on "Tightening a Loose Omega Action", and have used that advice in the past. Because of the geometry of things, I didn't think that would help in this situation, since the gap is more on the side than top. But I did move the nut two flats tighter, and it did lessen the gap a little, about to where the blued barrel was. However, now the action is tighter than I like it, but I'll leave it alone for now.
Both of the lugs are bolted on. There is, however, no way to adjust them because of dovetail fittings and tapered screws.
In the photo of the breech face, you can see by the wear marks where it is contacting the barrel, about 7:00 from the rear).
More info forthcoming.

 

[BuckDoeHunter]

Good pics. Without the firing pin bushing in place, do you think filing that 7;00 area some would improve the fit of the breech block against the barrel?

 

[goco4game]

Good pics. Without the firing pin bushing in place, do you think filing that 7;00 area some would improve the fit of the breech block against the barrel?

Yes, I had thought of that, or filing the mating surface of the barrel, but it seems so drastic! You remove metal and there ain't no turning back!!
My next thought was to remove a tiny bit of material from the front left side of the 1/4" pin, allowing the breech to self adjust to the rear of the barrel? If I mess up, I just start over with a new inexpensive pin. As stated earlier, I have to make new pins anyway, which I've already purchased at my local hardware store. Conveniently, they are exactly 1/4" and 3/16". I just have to cut them to length and knurl them to stay in place.
What do you all think?

 

[goco4game]

Yes, I had thought of that, or filing the mating surface of the barrel, but it seems so drastic! You remove metal and there ain't no turning back!!
My next thought was to remove a tiny bit of material from the front left side of the 1/4" pin, allowing the breech to self adjust to the rear of the barrel? If I mess up, I just start over with a new inexpensive pin. As stated earlier, I have to make new pins anyway, which I've already purchased at my local hardware store. Conveniently, they are exactly 1/4" and 3/16". I just have to cut them to length and knurl them to stay in place.
What do you all think?

Correction - I meant to say, "remove material from the REAR left side of the 1/4" pin".

 

[goco4game]

Good pics. Without the firing pin bushing in place, do you think filing that 7;00 area some would improve the fit of the breech block against the barrel?

Just an update on this problem. Yes, the wheels of progress move very slowly at my place.
After further consideration, I did take your advice of removing material from the breech block. I used a file to remove only a tiny bit at a time, checking often for fit. Then I moved on to finer abrasives and finally re-blued it. It now has a nice snug fit with no gaps. I've fired about 25 robust rounds through it, and everything is working perfectly well, as it should. The added benefit is that now with the Bestill breech plug with carbide insert, I'm getting no primer leakage.
Thanks again, BuckDoeHunter, for all the advice.

 

[BuckDoeHunter]

Your welcome, I'm glad everything worked out well.