Getting a Thompson Center to Group

.308win

New member
A friend of mine has a TC with 1in28 twist and is having trouble getting it to group. What saboted slug and charge would be a good starting point for him?
 
I've got an Omega. I get excellent groups with 100grns of loose 777 and either the T/C SST or Hornady SST's.

If he is using pellets, I would stop right there and go to loose. The key to good groups in a muzzleloader is consistency, consistency, consistency. Every powder charge has to be measured the same way. Pellets are notoriously inconsistent. Also, do a wet patch, then dry patch after every shot (including removing the breech plug to prevent the crud-ring buildup). Finally, make sure the bullet is seated with the same pressure for every shot.
 
When I bought my first Encore, I went through about every load,sabot,powder,primer,combination you can imagine.
I finally found my best groups came from MMP sabots, 90 grains (loose) 777 powder, 240 grain Hornady XTP bullet, CCI primers, with packing pressure of 45 lbs.
Shot preparation is one wet patch (windex) and 2 dry patches, between shots.
Stay away from pellets if you want to shoot groups at the range. They are fine for hunting if you just want to hit a 4" circle on the side of a deer, but you are not going to get 1" groups at the range at 100 yards with them, normally. There are a few guns I have seen that will shoot well with them, but not very many.
The most important part of the combination is the sabot. Thompsons are picky about the sabots they shoot, and even their own Thompson sabots are not always the most accurate.
Your rifle will probably be fussy enough that you will have to play with a few different ones before you find exactly what it likes to eat.
As above poster mentioned, being consistent is everything with a smoke pole, so make sure you do everything exactly the same way, in the same order for the best results.
 
There's a couple of major sabot manufacturers, and MMP make sabots having different outside diameters. Harvester sabots are ribbed. A variety of sabot types may need to be tested along with different bullets, powders and loads. 90 - 100 grains of powder usually works, but a little less could be a starting point from which to gradually increase the powder charge in 5-10 grain increments especially if shooting the more powerful 777 loose powder.
Shooting at a moderate distance like 50-70 yards helps for accuracy testing by reducing sighting/shooting errors.
The most popular bullets seem to weigh about 240-250 grains.


http://www.mmpsabots.com/

http://www.harvesterbullets.com/
 
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I can't get my .50 CVA to group with anything but a Thompson Center Maxi-Hunter but it shoots wonderfully well with that. I use the 285 gr one and my little gun will shoot cloverleafs all day.
 
my thompson likes 100gr.777 cci primers,300gr,hornady xtp;s with knight sabots and pack powder tight.also i paint my rod so i get the same pack,depth each time.shoots 1,746 fps.
 
Since I started this thread I thought I owed a status update. My friend got his Thompson shooting really well as he says (I haven't seen the targets) that it will shoot clover leaves at a 100 yards with a scope. He did just get back from Kansas and took two deer at reasonably long ranges for a black powder rifle. His solution came in the form of propellant, projectiles from a specific supplier, and replacement of a part (pin or pivot part in the take down mechanism I believe it was). I apologize that I am not more specific but if anyone wants the specifics post here and I will get them and post them.
 
Glad to hear that your friend found his right combo for his rifle.each gun is different ,some shoot good with 150 gr. powder, others 100 gr. same with bullets,etc.It took several tries for me before i found what worked best in my cva .50 cal. hunterbolt. but what a great feeling when ya finally do.
 
Possibly the wedge pin that holds barrel to stock??? A loose fit will let barrel float. As with Articap, would like to hear more.
 
He got the bullets and a kit to convert the ignition to small rifle primers from here. He didn't use pellet propellant. And, I was mistaken on the take down part; he did not change any parts on the rifle other than the ignition pieces to convert to small rifle primers.
 
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