Choosing cast bullets in case I get a 45-70

I'm thinking that the next logical step in my development is to play around with a 45-70. Consequently I want to figure out what projectiles I should be using so that everything can fall into place quickly when I get the urge and the opportunity to splash out on a new rifle.

I know that the 405 grain projectiles are the standard for this calibre. However it is the diameter of the bullet that I find attractive, and I figure why waste lead (and powder) unnecessarily? A 340 grain bullet has a sectional density of over 0.2, which seems plenty for me considering that my 125 grain .357 bullets work well with an SD of around 0.139

While the theoretical best procedure for selecting a projectile involves slugging the bore and making careful measurements, I like to trust that a new rifle will have a bore with standard dimensions and I like to be able to just buy a standard mould and use the bullets as cast. This has worked well for me with .308 and .357 rifles.

I like the look of the Lee 457-340-F mould, but I'm perplexed with its nominal diameter being smaller than the nominal bore size of a 45-70 (considering that the other Lee moulds I've got are labelled as 0.001" bigger than the standard bore diameter). I assume that Lee know what they are doing, and I'm willing to buy a mould and try it.... but I am a little nervous about the sizing, especially when I consider that a couple of their moulds are sized at 0.459" which I think is the 'correct' diameter. Initially I would be casting these bullets from soft lead and shooting them around 1000fps, and I'm thinking that a quick shunt up the rear end with Trail Boss or another pistol powder might increase their diameter a little. Dunno. I've also read that using Alox lube can add a bit to the diameter. I could go to the trouble of paper patching or powder coating, but I don't want to.

Or I could simply get a .459 diameter mould and send extra lead downrange with a bigger bang. But I'd rather use the lighter projectile.

It would be great to read comments from folks who've had experience with this type of thing. Thanks in advance. Best wishes.....

I think that the '45' calibre handgun moulds are .452" inch in diameter... smaller again.

I'd only take a lighter bullet if it were a hollowpoint. Lyman do a 330gr one. Otherwise if they're all flat noses then I'd take the extra mass - it isn't going to make the bullet perform any worse so long as it's stable, possibly slightly less drop, the amount of extra powder required creates better case fill, the increase in noise is small, increase in recoil = more fun, and unless you shoot lots of them then is the extra lead required an issue?

.451, .452 for 45 colt etc, handguns, pistol Cal levers,
.458, .459 for 45/70, 458 win, etc.
lead moulds are often 1,2 thou oversize.
I've just bought a 45 colt lever, so am looking at NOE/lee moulds myself at present.

I look forward to progress reports Southernman.

Pommy, I think you are absolutely right and that the extra lead and powder is nothing compared to the results I'd be more likely to get. I'm thinking I'd probably end up getting the bigger mould (Lee 459-405-HB) because the bullet diameter is 'correct' at .459" and because the rifle would mostly get used just for hunting. Apart from developing the load, checking sighting and enthusing with others, there would be very few shots fired annually. But I'd still like to know why Lee make both .457" and .459" moulds for the same rifle when my understanding is that the groove diameter is theoretically .458" ... and often Lee moulds are made to be 0.001" bigger than groove diameter.

yeah 452 is for 450 bushmaster and 457 or 459 is for 45-70

i have a 500ish gr mould for 4570, a single shot h&r that needs a fireing pin finished(iv had one made but its not perfect and some dies and cases)
its nothing top end but is a sold suppressed rig that would stop damn near anything

405 is the "std" based on over nearly 150 years of experimentation. The 405 has better long range performance than the 340 which will loose speed much faster.
Cast bullets can be pushed to around 1800 perhaps a bit more with gas checks but the original specs push it along at approx 1400 fps and its perfectly predictable and it works.

shootersnz /Robert makes lovely projectiles for the big guns.....the hollow base are lighter than the solid base jobbies...they seem to go well out of my barrel insert/rifle and would be the logical place to start.

Thanks for the comments.

I sent Lee Precision an email asking about the different diameters for their various 45-70 moulds and got this reply:

"Over time the inventory of molds that are manufactured and sold by Lee has been refined by the natural selection of customer demand. The .457" diameter bullet designs are the ones most commonly requested and used diameter so that is what Lee offers as standard inventory. This diameter tends to give the best all around performance in this caliber.

The two exceptions are the hollow base 459-405-HB which is typically used in vintage firearm that have worn or oversize bores. And the 459-500-3R that is a favorite for long range black powder competition."

All of what has been written in this thread is good food for thought. Much appreciated.

If you are loading for the most suppression & killing power, the heavier the bullet the better, as long as it can be stabilized with the twist you have, as 500gr at 1000fps has more energy than 350gr at 1000fps, don't look for expansion in .45 or over, just projectile placement & straight line penetration .

Use as large a Meplat bullet as can be found, trajectory is not effected enough it this case as 125yds is a long shot !

I agree Scout. I think that 100 yards is almost too far. With a lot of experience... or maybe rangefinding gear and a mil-dot scope you could have success at longer ranges as there should be sufficient energy at a considerable distance. I think sighting the rifle in for 'zero' at maybe sixty yards is a practical idea .... along with being prepared to not take a hasty shot over 75 yards.

Yes bud, as I said to you before, if subsonic 100yds if far, crosshair at 50, post at 75 & post top of shoulder or a little light in between at 100 as I remember !

Bit like a .22LR with subs from memory but it has been a long time since I tested this .

By the Bullet Energy Calculator -

500gr @ 1000fps has 1110fpe

350gr @ 1000fps has 777fpe

300gr @ 1000fps has 666fpe

So 45/70 with 500gr is near double a 44mag with 300gr in subsonic mode

It has the same power as a full load 44mag out of a 6in Revolver with the 240gr slug at 1380fps, which is considered a powerful pistol usable to 75 maybe 100yds with a experience shooter !

But not really that great compared to almost any half decent rifle cartridge !

When I was learning about my .308 subsonic rig, I made up a 'target' consisting of two-inch squares sitting on top of each other in a column. I painted the squares so that they were alternately white and black. I spent a bit of time looking through my scope at this trying to develop a system of estimating where I should hold for varying ranges. It was helpful, but judging the range, unaided, in hasty circumstances in different terrain, while not knowing for sure whether it is a big or small animal I'm looking at, is a challenge for me. Like a lot of things though, practice helps.

And it seems that sometimes the Goddess of the Hunt smiles upon me. This isn't a subsonic story though...... A few years back I was staying at a place in Marlborough where I'd been trying to get a deer. I went out on what I seem to recall was the last morning of that holiday. I had a Lee Enfield that had started life as a .303, but my Dad had converted it to shoot the more plentiful 7.62 x 39 ammo. I had military-style ammo in the magazine, some of which I'd drilled. Suddenly, I saw a small group of deer move around the side of a ridge ahead of me and they went out of sight. I moved quickly toward a position where I thought I'd see them again... but when I got there I found that they had travelled a long distance and were now well ahead of me.... and above me in elevation. I was keen to take home venison. I rested the rifle as best I could. My judgement of the distance was pretty much automatic or subconscious. I don't know how far away they were, but looking back it seemed a long way. One deer was standing broadside. I lined up the open sights on the top of its back, pretty much directly above the front leg. I fired, the deer leaped in the air like a Disney cartoon and disappeared.

I clambered up to the spot where I reckoned I'd seen it last and started circling around. The area was scrubby, but most of the vegetation wouldn't have been taller than my waist. I looked around for a long time. Then I smelled 'deer'. I took a few paces upwind and there was the deer... shot right through the heart, lying only a short distance from where I'd shot at it.

Now you've got me started....

The story above reminds me of the only pig I've ever bagged with a home made bow and arrows. My bow was made from a rare straight limb of the native Olearia paniculata. My arrow stems were made from dried bracken stems. The fletchings were canada goose feathers. My point was made from stainless steel sheet and my string was made from synthetic cord. I was hunting in a place where, theoretically, I could have caused a stir if seen. I used to easily get permits to hunt on this (what I'd call public) land, but they'd become more difficult to get and they used to specify the weapon I could hunt with. A homemade wooden bow might not have been approved. This is a long time ago now. Anyway... I thought I might have come across a goat, but instead I chanced upon a mob of pigs... the ones I could see were big and they were taking it easy lying down in the shade. I decided that they were too big and too far away to shoot at. My bow had a draw weight of around 35 pounds, the pigs were in the 50 to 120 pound range and they were further away than my comfortable shooting distance of maybe fifteen to twenty yards. So I thought I'd just watch them. But then a smaller pig (maybe thirty pounds) walked out of the scrub about ten yards away. I drew and shot. As I released, the pig (as if manipulated by the Hunt Goddess) sort of pivoted on the aim point and stood in a perfect 'quartering' position. The arrow buried itself into the black hairy mass and the pig ran out of sight. The other pigs disappeared.

I thought I should do the 'textbook' thing and wait for maybe thirty minutes before going after the pig. You know... don't get its adrenaline going ... let it lie down and stiffen up etc. But after a couple of minutes I couldn't bear it. I took a few paces forward, and there was the pig absolutely dead just a couple of yards beyond where I'd shot it.

And another story... related to the converted Lee Enfield..... I borrowed a motorbike and went up to a hunting spot (in Marlborough) quite some distance from where I was staying. It was getting fairly late and back then I was not equipped with the fantastic LED flashlights that I have now. I had nothing. I left the bike on the track and did a circuit in the open bush. A stag ran across my path and I took a quick, quartering shot. It dropped. I worked fast in the failing light to skin it, cut it up, and jam it in my canvas meat pack. I found that the drilled bullet had broken up fairly soon after impact in the gut area, but the tiny hardened core (steel? tungsten? dunno) continued and penetrated the heart (must have been the Goddess at work again). I got back to the bike and was pleased that the headlight worked. I had the meat pack and the rifle on my back, and I bundled the skin and tied it to the handlebars. All went well until I got to a particularly rocky, rutted, steep bit of the road I had to go down. With the bouncing, the deer skin worked loose and a flap kept covering the headlight. At the same time my heavy meat back was swaying about making things difficult balance-wise. I am not Evel Knievel, and I was unwilling to let go of the bars with one hand to sort out the skin. It wasn't easy to stop while trying to negotiate the deep ruts. Then the flap completely covered the headlight, the front wheel hit something or went into a rut, and I fell off. The Goddess was probably pissing herself. I recovered... made the bundle of skin a bit more secure... and rejoined the family at the house without further incident. I made a nice (crude) rawhide arrow quiver out of that skin.

I'm continuing to play with subsonic rifles. I fully agree that they don't compare well to standard hunting loads when considering energy and range... in fact, I have a whole new appreciation of what even a little .223 projectile can do. But considering that I've had success shooting goats and pigs with standard velocity .22 rimfire ammo (and before someone else says it, this is not a recommended cartridge for this type of game), the energy of a 300 grain projectile going 1000 fps is comparatively huge compared to a subsonic .22 which has only about 92 foot-pounds at 25 yards. That 660-odd foot pounds is over seven times the amount of energy carried by the .22, and the bullet hole is over twice the diameter. This is miraculous stuff compared to what I've hunted with.

I do believe though, that if a man is going to have a suppressed 45-70, he may as well use the heaviest bullet with the flattest nose that shoots accurately in his rifle. That Lee 457-405-F looks pretty good, but if I can't get the mould (or suitable ready-made cast bullets at the right price), then I will be more than happy to try anything that fits. Having got myself all enthusiastic though, it may be months before I get the rifle. Maybe something else will come up meanwhile. But it is all an interesting adventure.

Excellent post & great story's !

Thank you for posting lol !

If you cast the 457 bullet out of nice soft pure lead it should expand into the bore when fired
You get this alot with muzzle loading firearms which are designed to shoot a projectile rather than a ball
It would be almost impossible to load the rifle if the bullet was oversized
So the projectile is actually supposed to be undersized often times the projectile amost falls down the barrel and you just give it a slight tap with the ram rod to be sure it’s seated on the powder

The projectile is cast from pure soft lead and the pressure expands it into the Rifleing when fired

A mate of mine swears by a 457 in his 45/70
Mine likes a 459
Just comes down to the gun and Experimentation

Thanks Rambo. Of all the readily available moulds, the one that appeals the most is a .457, so that's probably what I'd start with.

As I read posts on this forum I'm thinking that there might be quite a few 45-70s being used in NZ.