45-70 rough nose after casting - how to minimize?

[kenn]

I just cast a batch of 45-70 using the lee 459-405-hb and since it casts nose up, the sprue plate cuts off at the nose. I'm opening the sprue as soon as the sprue pour "frosts". At this temp, the lead is still easily crumbled but not still molten. I get a fairly rough nose. How do I go about getting a smoother nose? Do I open the sprue sooner and let it smear a tad or wait until it is a bit harder so it "cuts" it more cleanly?

[Toymaker]

You don't want it to smear, that just leads to even more problems, so try cutting just a little later. I've a Hoch nose pour mold for my 45-70 and have had the same issue. I've found the nose is less important than nice clean, crisp, sharp base edges. What hardness lead are you using? And let us know how the bullet shoots. I considered one once, so I'm curious.

[Tom Trevor]

What alloy are are you using? I cast that bullet with 25-1 lead tim mix and the cut off is smooth afier 5-7 seconds. hard alloys with antimony usually are rough. A friend just bought two of the latest improved moulds thinner with guide pins. Sad to say it casts .457 at the front band getting to .459 at the base and several thousands out of round. What weight and size do you get.

[kenn]

I haven't even weighed them yet. I'll do that tonight. I am using about 70% COWW and 30% SOWW so I'm nowhere near pure.

[wallenba]

Just as it frosts over may still be too soon. The spue is tearing out, not getting cut I think. I test mine with a very long pointy tweezer. I poke at it and feel the hardness and whether or not it leaves a deep mark. It'll sound different too.
You can also try 'parking' the flat bottom area of the spue plate over the spot and pressing down a bit with your mallet. That helps in flattening sprue bumps.

[QIDPlb]

Just let it sit for a while. Might be cutting it off to soon. I typically have 3 different mould when casting for 45-70. Gives the allow time to solidify.

[kenn]

I'm pulling that sprue immediately upon frosting like I do my base pour mold. I've not done a nose pour until now and was always worried about snapping the crappy lee potmetal sprue plate handle. In this case, that's not an issue so I'll try letting them go a bit longer so they don't "tear".

I weighed 5 casts and got the following:

1-395.5gr
2-398.5gr
3-397.5gr
4-396.0gr
5-397.5gr

Average 397gr. This is without about 70% COWW and 30% SOWW.

[Tom Trevor]

Would you mike a couple and let us know the diameter at the front and rear bands.

[country gent]

Let mold cool a little longer, A small fan can speed this up. Also make sure sprue plate is flat and sharp. Just letting it cool a little more may work, But if there is a flat or dull area then you may have to do a little work on the sprue plate it self. Not a real big deal. A 1/2 multi flute counter bore turn by hand in drill press to make any flat just disappear. then a light stoning to remove any burrs on bottom. If just dull a light stoneing on bottom should tune it up.

[John Guedry]

I have the same mold and it doesn't make a super pretty nose. I just dress it up a little with a file. Still shoots straight.

[JSnover]

A wise old BPCR shooter with a handful of trophies told me years ago, "worry more about the base. That's the steering wheel of your bullet."

[kenn]

Would you mike a couple and let us know the diameter at the front and rear bands.

Strangely enough, they are casting out of round. .459 thinnest, .462 widest. I have a .460 sizer coming from Buckshot and I'm fairly certain the .459 will come up to .460 they the are pushed through.

I also just ordered the .457-340 and I'm going to try to lap it up to .460 so I can get a bit more mileage out of my lead and get twice as many bullets per pour.

[Tom Trevor]

Great! as I said earlier mine is .457-.459 and out of round!! At least yours is a bit larger.

[wallenba]

Probably widest diameter is across the parting line, usually is in these cases. Easy fix is some Beagling tape (400* furnace tape from hardware store) on one mold block.