Cast bullets in Thompson Impact

I just got a Thompson Impact 50Cal the other day from Cabelas (on sale for $200 ). I have only owned and shot a old flintlock before with round balls that I cast myself. For the Impact I am looking at casting full bore bullets for it. I notice there are literally hundreds of molds a guy could get, I was wondering if anyone had some luck with full bore bullets in their Impact and what mold they have used? My primary focus will be hunting in muzzle loader season for whitetail and mule deer (if drawn) as well as some target shooting in the off season to keep the skill level up and play around a bit. I am 100% not interested in using sabots at this point, though that may change once I get into it some more. I have a abundance of lead at home for casting (old shotgun slugs from a range cleanup)

Lewis/GM will be along shortly to help you out, they know all about different molds.

Does that Impact have the false muzzle on it. If so you would most likely have to cut it off to get decent accuracy with conicals. Probably want something about an inch long or less if that is a one in twenty-eight twist. I would push an oversize ball through that barrel and find the land to land measurement and get a mold that would cast a lead bullet or a one part tin to forty part lead bullet a thousandth or two over that. Good Luck

One way to try it for accuracy is just get you a box of the TC Maxiball conicals and some felt wads and try it for consistency then you will have a good idea if the qla needs cut off and recrownd . But I would agree Mr Lewis and Mr GM are a welth of knowledge when it comes to conicals and casting molds.

Sorry, it is a 1-28 twist barrel and the first little bit is smooth bore before the rifling. I unfortunately did zero research before buying it as it was on a one day sale and sold out very quick. From what I have read, most people had nothing negative to say about the gun, so I think I lucked out. From a beginner's perspective it seems well built and well designed. Definately significantly more advanced than my old flintlock rifle.

The Impact is a dandy gun to start with and for mulies and whitetails but I'd stick with the sabots and a good jacketed bullet. The Impact is a light gun and if you're shooting the 209 powder, which the gun is compatible with, at 110 grain by volume with a 300 grain bullet/sabot you'll be getting an eye opener for recoil. Lighter bullets have less recoil but lose effectiveness at the longer ranges and smaller charge weights will kick less but also suffer with distance. Accuracy will be fair out at 200 yards but you can expect very good accuracy at 100.

I tried some lead full bore bullets in one of my Impacts and got zippo for any sort of accuracy largely due to the muzzle's rifling set back. You can try lead full bores but I'm willing to bet you'll either sell the gun, cut the barrel off or settle on sabots.

As Tom mentioned above, I will ad to it, TC’s QLA Muzzle is a BAD BAD Deal for Full bore Lead Conicals, If you do try them, i would put them Straight on the Powder, NO Over Powder Wad. My Experience with TC’s QLA Muzzles were HORRIBLE. If it were me, i would cut the Barrel Back and Re-Crown it. I know SEVERAL Good Conical Bullets for the 1:28 Twist, i have 4 of Them that are WELL Proven

In case you don’t know what the QLA is, it’s this little Mess right here. Whoever thought this was a Good idea, Should have to Sleep with one Stuck somewhere

Interesting, so is it just pressure imbalances that mess things up when it gets to the muzzle? Because you wouldn't think the bullet would contact that area at all as it left the muzzle.

No contact made but the qla is often not centered with the rest of the bore. Creating un-even gas pressures around the bullet as it reaches the muzzle thus throwing off its trajectory. Saboted bullets aren’t effected of course because of the sabot

No doubt cutting off the QLA will most likely improve your groups. My groups went from 4-6” at 100 to right at 1” after cutting my QLA off. I measure mine in my lathe at 0.004” out of center.
I’m a fan of conicals, so after getting my first in-line I made a mold and started casting, shooting and hunting.
Good luck.




330 yards in 1st NMLRA match.
2 sight adjustments after 1st & 4th shots.

I guess I will just have to try it and see how it shoots..