Picked up a new to me Jones and Garner "Grand Rifle". 50 cal, 42" barrel with roughly 1:22 twist. I'm messing around with the stock of bullets and powder I have on hand and I'm shooting fairly well with 75 gr of Black and a 275 gr T/C Maxi Hunter.
Primary use for this rifle is accurate hunting. Knowing that all rifles eat differently I was wondering if anyone had a bullet they had good experience with before I buy blindly and hope for the best. Right now I'm grouping about 2-3" at 100 yards but I get the feeling this rifle can shoot better than I can and I'd like to feed it better.
It will stabilze anything up to 800 grains or so. But if you must do this the below recommended 50-70 bullet sized to fit should work. Hunting? Conicals were pretty much discarded as ML hunting projectiles, no matter what Ned Roberts says. In order to get a 450-500 grain bullet to decent velocity (lighter bullets have little advantage over a RB) for a flat trajectory the recoil will be an issue. Since the longer the barrel time the more impotant uniform holding becomes. And this goes for EVERYTHING even HV modern stuff. 2-3” at 100 if the recoil us heavy may be all you are gonna get. When its on at 100 where is it at 50? And unless you have a range finder and an adjustable tang sight shots past 100 with a high trajectory load is very risky. Depending on the lenght of the 275 gr you can probably get by with a 60 or 70” twist if the grooves are under .006” deep. ALSO bullet lube can be a factor. Hard lubes can adhere to the bullet and unbalance it. SPG will work fine especially if pan lubed. I would also recommend a thin card wad, like the cardboard in a cereal box, that is slightly over groove diameter with the bullet base carefully wiped of any lube is a good idea. Black powder will put divots in the bullet base otherwise. You can get a wad punch from a supplier like Buffalo Arms.
The Maxi-Ball and the “improved” Maxi-Hunter came about with the mass produced MLs of the late 1960s and early 70s. This has evolved into the plastic saboted pistol bullets. People buy them for a couple of reasons. First when they first came out and the T-C and others were buying ADVERTISING in mags like Guns and Ammo the gun writers, who were generally completely ignorant, started telling people that a round ball would not kill anything since it had such a low ballistic coeffcient. This of course is complete buffalo bagels otherwise the long hunters would have been wasting their time and Lewis and Clark starved before getting to the falls of the Missouri. But since the gun writers said so it HAD to be true? Right? In my experience, unless a very heavy bone is encountered a 490-530 RB will give about 30” of penetration on a deer, or pass through on lung shots even at 800 fps. Yes I have shot a couple of critters with a 6” 50 cal belt pistol that made 800 fps one was a follow up on a buck that was still alive as I approached. Gave about 20-25 in of penetration from shoulder (missed the bone) to offside hide at the diaphragm. The other was an antelope with a broken jaw from a modern hunter I came across after the fact. Side to side pass through and a plume of dirt in the sage brush beyond. SO big I though I had missed. I also shot a MD doe with a 54 pistol with a velocity over 1000 that broke the humerus (many pieces), took the top of the heart out and lodged under the far side hide. This was about 25 yard shot.
I did, back in the mid-late 1970s, test a 54 maxi-ball vs a RB on a baffle-board. The Maxi-Penetrates about 30% farther than the RB. But since the 54 RB would pretty much shoot through a deer from chest to rump why do I need more penetration? All I proved was that if you shoot a Maxi-Ball from a percussion you better buy a platinum lined nipple. Oh and that “naked” bullets in MLs can slide away from the powder in not carried muzzle up or at least level.