frustrated at the range

Hollow based bullets as any bullet loaded into a muzzleloader MUST be a snug fit if they are to be accurate.

My best results were when they slightly engraved upon loading. Too - they were pure lead only.

24” is a wonderful twist in a .50 rifle.

Pedersoli makes an English style 1/2 stock fast twist rifle, patterned after a Rigby(but I thought .45 cal). I was not aware they made a fast twist Hawken replica.

The 24” twist will stabilize bullets to 600gr. easily, but the stock (and butt plate) might not be up to the recoil such a bullet will provide.

A 450gr. bullet should easily shoot into 1 1/2” at 100 yards. My .50 McGowen barrel on a rolling block, 24” twist shot the 520gr. Lyman bullet into 1 1/2” at 200 yards with 86gr. BP.  I only did little testing/fireforming actually with the 450gr., pointy bullet, unfortunately- but- in an original .50/70 carbine barrel, it shot 3” for me at 100 meters wioth 70gr. of 2f GOEX. That means with better sights, and a new, properly twist barrel, it should indeed shoot well.

You might need to put down a wad between the powder and the bullet base. You might be able to get appropriate sized wads (card or certainly Walter vegetable fibre wads .50 cal. or 32 bore. from Trackofthewolf dot com.

Pure lead should be used. Breech loading BP slug guns use 40:1, 30:1, 20:1, or whatever works in tin to lead- or WW and pure lead mixes.

Pure lead usually works best in a ML due to the amount of slugging up, ie: obturation (expansion via shortening up) it must do to fill the grooves and seal- immediately upon achieving ignition, before it can gas cut. For this reason, a wad sometimes helps.

I would expect a .50 cal with 400gr. to 500gr. bullet would shoot best in that twist with from 70gr. to 110gr. I would certainly start with the lower charge. Squib loads, ie: pistol loads such as 50gr. will not see good accuracy at long range, I would not think. Best to find an accurate load for all ranges.

Be prepared to have to replace the nipple often - slug guns work at much higher pressures than round ball guns and wear/burn out the nipples quickly. Some of the picket bullet shooters replace stainless nipples every 15 shots. Much depends on the stiffness of the mainspring when the hammer is down on the cap. One saving grace for this rifle, is the calibre. A .50 operates at lower pressure than a .45, given the same bullet weight and powder charge. Lower pressure means the nipples last longer. Some of the serious muzzlelaoding bullet shooters use platinum lined nipples. They cost around $80.00 each, I'm told.

Yes- should have mentioned. Wide, square bottomed grease grooves are best. The Lyman #515450 mold, Lee also makes it, was designed for black powder loads. It is the original .50/70 and .50/90 design.  3 wide, square bottomed grooves.

Cast from pure lead, then fill the grooves with lube - 60%Beeswax/40% Vasaline works beautifully - or SPG - or Lyman BP Gold - no ALOX!!!!!!!!!!!!!! After casting and lubing they can be sized down - you will need a sizer for this mould but it is the best mould/bullet for your purpose that I can think of.   Lee Precision will make you a sizer for abotu $25.00 or $30.00 that fits a normal 7/8x14 loading press. Simply lube the bullets with your fingers or on a tray and use hot lube, solidify method, then push them throught he die- instantly made to correct size.

Since your bore is .503” - that is what the final sizer die should be - .503". This is probably too much of a drop in one pass from .515” - so you might need to buy intermediate dies at .511” and .507".  I size lubed WW or softer bullets down .009” without any damage at all in a die I cut myself. I use the same die for sizing down jacketed bullets - without damage, but in 9.3mm size.  I have friends who have had Lee make them dies for sizing down jacketed bullets and their intermediate dies (2 or 3 die set) works well. perhaps only one intermediate die would be needed for lead only, and soft lead at that. Be aware, if pusing on the nose, you will change it's shape. A properly shaped nose punch will make it a nice flat nose shape for you - or even a perfect Round Nose. Flat is better for hunting.

BTW- before buying a set of sizing dies for bullets, take a bullet of about .515” diameter, lube it and shove it up inside a .300 magnum FL sizing die varying amounts then push it back out.  You will probably find a depth that gives you a perfectly sized bullet.  If you push them in, base first, you will end up with a slight taper, base to top.  Both ways can be tried.  I would try the base first, first, using a normal Lyman or RCBS bullet sizing nose punch to push with, in the loading press's shell holder. At some distance intothe die, the size will be perfect.

A .300 Winchester mag, or 7mm Rem mag, or any short magnum die will work.  A .375H&H die or.300 H&H die will give an even sharper taper, which might be just wonderful. The larger the diameter of the 'ejecotr rod, the less damage to the bullet's nose when pusing it back out.  A .458 mag die will allow about the largest size.  A .350 Rem mag. die would work well, too.

This is what experimenting is all about.

Good luck. Glad to help if I can.

  Exciting, isn't it.

oops should have read my other post first.