I'm going to have to go back and retool my failed TCU loads also. I had been seating the bullets way out. Same for the 7-30 waters. I had higher hopes for both. Hopefully this will produce better results.

Seating up to lands does not work this cartrige, (have no idea why) take a fired case fill with your charge then drop in the bullet, measure OAL without crushing and write that on the wall. 100% case fill seems to be the ticket. Yes I have tryed compressed loads.
120gr bullets forget completly, they keyhole turkeys. 154gr hornadys work well out to turkeys, Boat tail 150's are fine all the way to rams. I am working up a Horn 162btsp load. not good so far but they sure work excellent in the 7 merrill. Horn 162BTSP interloc using 22.5 gr N133 OAL 2.600" was complete failure. Group size too large to measure.
I used 23gr of A2015 in the TCU (I have rimmed TCU called 7UR in XL) under Horn 154gr for long time. Many 40's and 60"s. OAL was 2.600". I now use that gun for standing only taco hold so 22gr A2015 under 150gr Seirra BTHP match when I can get em. other wize use the 154gr Horn. OAL on the 150 is 2.550" and 2.540" for the 154gr.
I also tryed N133 powder and went back to the A2015. Maybe due to the 10" barrel not burning slower powders. Since the cartrige is over 2 3/4" long you are only left with 8" of rifling.
Looking for dies and load data for 270 max for next standing gun.

What If.May not be a load problem.TC has been shooting perfect scores since day one,and still do.But they have to be to be right! If you can find someone in your area that knows what to look for this may help you,I use to have every part for a TC back when I own one,over size locking bolts,springs.Not even sure that you get the proper parts these days and keep production legal....Just a thought

I just did some load testing on my 7TCU as I have been trying to find out why I suddenly started ringing soo many targets (including 1 turkey).

First, My 7TCU barrel is an oddball. it has a short throat, 1:9 left hand twist!

original load was Win case, Fed 205M primer, 24.0 grs of IMR4895 using the Hornady 154gr FB (#2830) seated so bottom of bullet even with bottom of the neck.

all groups shot 1" or less at 100 Yards for 5 shots. Chronograph testing was done with 10 shots.

24.0 Grs of IMR4895 chrono'd at 1510 fps, SD: 12fps, ES: 60fps
24.0 grs of H4895 chrono'd at 1572 fps, SD: 10.2 fps, ES: 48fps
24.0 grs of VHT N135 chrono'd at 1652 fps, SD: 16 fps, ES: 48 fps

I also tested a Hornady 162gr SST with 24.0 grs of VHT N135, the chronograph readings showed good, but groups were not very promising. the Chronograph showed 1683 fps, ES: 38 fps, SD: 12 fps. But it would not group better than 2" at 100 yards.

might help you to find a good load!

Trigger pull is a personal thing, all my Contenders brake at 10 oz. or less. I'll bet that Plama rifle doesn't have a 2# pull ?
If you have a shooting buddy let him load and then hand you the pistol, occasionally not loading a round, you may have a "master trigger linkage" problem
Forget about anything fancy BTHP's, polymer tips,ect in the bullet dept. What bullets do bench rest shooters use to shoot in the "1's" ?
See if you can find any SR 4759, either an 8 oz can or see if you can beg borrow or buy enough to load 20 rd's. Fill a case to the base of the neck, then seat a 154 or 160 fb bullet to the powder if you want a 1 load system, or use a 139-140 for the C, P & T.

Just my $0.02