T/C Omega won't group.
 

I've been trying to get my Omega to group.
I've floated the barrel by sanding down the synthetic stock pressure point. It didn't seem to have any effect. The groups were the same before floating the barrel.
I've tried 120gr. and 110gr. Triple 7

When I bought the bullets, Ray of http://muzzleloadingbullets.com said, 120gr. of Triple 7 was the load producing the best groups. Not for me. I reload and shoot bench rest. This is frustrating. Any ideas?

SEE ATTACHED TARGET IMAGE
Bullet
.40 Dead Center - 240 grain -120 gr. Triple Seven FFG

Check the sights, then it's time for load variation. Change up your powder charge from 80-140gr in 10gr increments and then fine tune. Bullets and sabots. Too many combinations to list. Pick and try.
My T/C Omega shoots 250gr Hdy SSTs, 240gr Hdy XTPs, and 240gr T/C Cheap shots well with 130gr RS.

Open sights? What distance?

When all else fails in a INLINE rifle I start at 80 grains of Pyrodex RS and a 250 grain Shockwave. I can normally get that to start grouping. Start at 25 yards and shoot a three shot group. It should be VERY TIGHT in the group. Then kick it up to 90, 100, and so on until the group starts to open up. Move the sights to be dead center bull.

Then move back to 50 yards and try the load that did the best for you. What kind of group did you shoot here? If it was good, then move back to 100 yards and do it all over again. Be sure to swab between shots.

Now I do not own an Omega, but have handled them. They feel like a real nice rifle.

Muzzleloaders are NOT centerfire rifles. What shoots great in one rifle may not shoot worth crap in another. You will have to try different bullet/powder combinations to find the sweet spot on your rifle.

And you don't have to start with magnum loads (and 120 gr of 777 is a magnum load). Try starting at 90 gr and shoot three times, then 95 gr, shoot three times, 100 gr.........up to about 110 gr. And you will have to try some different bullets.

You don't need over 100 gr of any powder to kill anything walking in America. My elk load is 90 gr or 777 or BH 209.

It may take a lot of work, but will be sweet when you find your rifles sweet spot! If not, you can send it back to T/C and see if they can get it to shoot. If they can't, they will give you a different barrel.

100 grains (normally 2 pellets) and 250 SW, with wet and dry patch between each shot works well for my TC Omega.

The Plastic stocks on the Omega are very sensitive to how the barrel and action are tightened up. Try setting the torque on the rear mount screw first and then tighten the front. Use the same torque each time. If it still has problems you may have to bed the action. My Omega shot great for a while then all of a sudden it started grouping all over the place. Action bedding was the problem.

In my Omega, two pyro pellets (100grains) and a 260gr Precision Elite.

You're too Hot
 

Had the same problem with my Omega. I was shooting 250 Shockwaves with 110 of T7 with no consistency.

I went to a 300 gn. bullet. and down to 100gns of T7. and started to group very well. ( 1725 FPS by the way )

If you're using a 240 grn bullet, try about 85 grns of T7. It's still plenty of power and will be on target.

I use to shoot the dead centers from precision in my t/c thunderhawk using 85 grains of 777 gun will groupe outstanding.
I think the over the 100 grains may be your problem.

+1.

I have a lot of experience with Dead Centers. While they are accurate and perform well on game, their soft lead construction will not handle velocities over about 1800-2000 fps well. Precision Rifle will not tell you that but I have shot them in enough guns and have enough shooting buddies who have done the same to see that we have NEVER found an accurate load over 2000 fps and 1800 fps is a more realistic limit in most guns; the bullets apparently start to deform over that.

You're just pushing them too hard. Back off on the powder to 85gr and work your way up in 5gr increments.

The other possibility is your gun just doesn't like them. The reason I stopped using Dead Center bullets was that I switched to my Omega and it would not shoot any weight of them accurately at any reasonable (85gr+) charge.