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Discussion Starter · #1 · (Edited)
Hello! Im trying to come up with a good load for the Cast performance 45-70 .458 405gn gas check with Vihtavouri n133 powder, but im having trouble finding good information on this online. Found one german guy who loaded 45.5gn with the same bullet and powder. I tried this load but i get alot of soot on the base of the case and unburned powder in the barrel.

I upped the load 1gn and shot 6 rounds, one of which left a clean barrel and case (maybe this was crimped better?)

The only book loads i can find on this powder thats close is with the speer jacketed 400gn round which starts at 47gn, but with the cast performance being a lead bullet you should lower the powder (or so i've read)

Being shot out of a marlin 1895 i dont dare to go too hot, question is where that threshhold is. Would be more than happy to hear your input :)

168381903_10159213434364660_4471689236457147707_n.jpg 167678183_10159213328139660_3975541081618388740_n.jpg

pictured is the 46.5gn cases and the barrel
 

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ast performance 45-70 .458 405gn gas check is what you have listed

if you use a gas check my understanding is you do not need to keep velocities below say 1500 fps to prevent leading. I believe the gas check alleviates this concern.

I have not used the n-133 in the 45-70 so I cannot comment on the loading levels. I would suggest the 1895 usually shoots very well in the 1500-1700 fps velocities. If you can target your efforts on the velocity it may come in line for you. My go to powder for the 45-70 is imr 3031
 

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Discussion Starter · #3 ·
I realise that a chronograph will be vital to find a optimal load, regrettably i lack the funds for it at the moment. Don't know what velocities I can reasonably expect with the shorter 18.5" barrel but I'd like to reach around 1600 fps
 

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It sounds like 46.6gn is your sweet spot. I'd concentrate on a consistent crimp (your observation) and go from there. All the cast data I just looked at said anything from 43gn to 55gn with a gas check. There were several barrel lengths mentioned.
 
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I never used that powder but you should easily reach 1600 fps velocity, not sure if I would want to shoot that speed out of my Guide Gun anymore though with a 405 gr. bullet. Not really that bad but for me, it has become so. I went down to a 350 gr. Ranch Dog bullet. Some powders just plain out shoot dirty but upping the powder charge and making sure you have good crimps, it should help. You have already figured that out though, I believe. Dirty, I didn't mind because I clean the rifle anyhow but unburnt powder can work it's way into the action parts and that's cause for concern.
 

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Looking at your cases my first question is, have you annealed the cases? Second question, how firm is the crimp? Third question, are you sure the powder in the barrel is not burnt? Fourth question, are you using magnum primers? I don't shoot bullets as light as 405 but have seen these same problems with heavier bullets and usually the cause has been one of the things I mentioned.
 

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I use Starline brass in my 1895 GG, which are pretty hard when they are new. As you increase powder, velocity, and pressure, they may start to seal better in the chamber and stay cleaner. My cases used to look similar to yours in the picture before I started annealing them. They stay pretty clean now, velocities are much more consistent, and I was able to lower the powder charge and retain consistent velocities and accuracy. As stated above, I would also use a good firm crimp.
I would not be afraid to use the same load for a cast bullet that the book data uses for a jacketed bullet of the same weight. All things being equal, a cast bullet of the same weight will have less barrel friction than a jacketed bullet and will generally produce more velocity using less pressure than a jacketed bullet using the same load data. 1600fps should be no problem for a 405grn cast bullet in your GG.
Just start low, like you are doing, borrow a chronograph if you can so you have some idea of where you are at, and be cautious. Straight walled cases do not act like bottle-neck cases when it comes to showing pressure signs. I would not keep adding powder until I see a primer start to flatten out in a straight walled case! Get a chronograph, it will be one of the most important loading tools you ever purchased. Good luck, let us know how it goes! :)
 

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Yes, get a chronograph at least sometime in the future. especially since you reload. You'll have an easier time coming up with a consistently accurate load for your rifle. There are plenty of good chronograph for under $130. I have one I paid over $300 for some 30 years ago and it works fine but was a pain to set up every time. I finally bought an under $130 Chrony and haven't looked back. They are easy and convenient now. I think Midway has sales on them now. Been awhile since I been to their site.
 

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Discussion Starter · #12 ·
Looking at your cases my first question is, have you annealed the cases? Second question, how firm is the crimp? Third question, are you sure the powder in the barrel is not burnt? Fourth question, are you using magnum primers? I don't shoot bullets as light as 405 but have seen these same problems with heavier bullets and usually the cause has been one of the things I mentioned.
1: I do not anneal my cases, they are brand new starline, ive read they need to be shot once or annealed to get the best seal.
2: I think i got a hard crimp, i make sure i cant see the inside bevel of the case after crimping if that makes any sense.
3: The powder in the barrel looks to be the same size as unfired, but they are golden.. Dont know what to make of that :unsure:.
4: i use cci 200 large rifle primers. So its not magnum :)

Im going to try again with 46.5 gn but this time make sure that the crimp is hard and even, i will aslo try to crimp at the crimp grove instead of going past it just to get 2.550 oal. This will make the oal somewhat longer and seat depth shorter, but not by much.
 

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Sounds like a plan...I would definitely crimp into the groove, just make sure the round chambers in the gun before loading the whole batch. Should be fine.
I assume you are using a standard seating die with crimp in one operation. You should be able to feel it on the press when the crimp hits the mouth of the case. Seat the mouth of the case to the groove so it has somewhere to go with the die backed out so it cannot crimp yet. After seating the bullet where you want it, back your seating stem off while you move the die down to adjust your crimp (you will feel it when it contacts the mouth of the case). After you get the crimp you want, move the seating stem back down to contact the bullet while the ram is all the way up and crimping the case.
Don't get carried away and crimp too hard, it may bulge the neck or damage the case mouth. If you get brass shavings, you may be hitting it too hard. You just need to angle the edge of the mouth into the groove. :)
 

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Careful on the crimp. If you are roll crimping, to much and it can actually decrease the neck tension on the bullet. The golden kernels of powder you are seeing, I do believe they are also burnt. I have seen the same results with some of my powders in working up some loads in my Ruger 77/44.
 

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I have always had to anneal Starline even when new, it is a hard brass. It is also a good brass, it's all I shoot in my competition rifles, I want to be clear that I am in no way knocking Starline. The annealing will soften the brass so it will seal more readily to the chamber walls, which should help getting rid of the blow back you are seeing. I asked about LRMagnum primers because they can blow the bullet out of the crimp before the powder flash hits the bullet. As to the unburnt powder, push some out on a clean surface, then inspect it maybe even roll some between your fingers to see if it is actually unburnt. Many people think that 5744 does not burn completely because of the residue in the barrel but it is far too accurate for it not to have all burnt, you may be seeing the same thing with the powder you are using. Your crimp sounds like it is firm enough, but as you said you will be crimping in the groove. Good luck getting this problem solved.
 

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Hello! Im trying to come up with a good load for the Cast performance 45-70 .458 405gn gas check with Vihtavouri n133 powder, but im having trouble finding good information on this online. Found one german guy who loaded 45.5gn with the same bullet and powder. I tried this load but i get alot of soot on the base of the case and unburned powder in the barrel.

I upped the load 1gn and shot 6 rounds, one of which left a clean barrel and case (maybe this was crimped better?)

The only book loads i can find on this powder thats close is with the speer jacketed 400gn round which starts at 47gn, but with the cast performance being a lead bullet you should lower the powder (or so i've read)

Being shot out of a marlin 1895 i dont dare to go too hot, question is where that threshhold is. Would be more than happy to hear your input :)

View attachment 842991 View attachment 842992

pictured is the 46.5gn cases and the barrel
Tactilever,

Welcome. Welcome to the wonderful world of cast bullets in hyphenated cartridges.

Here is a link to a post I started a few years ago. Within, you will find loads from mild to wild. All, loads that have been tried, tested, and you can be safe using.

Your choice of Powder, Vihtavouri, makes me I assume you are not in the US. You may want to consider Alliant powders that meet the environmental requirements, from what I have seen in articles.

Regardless, there are many hyperlinks in this post for published reloading data that should help. There is also a powder burn rate chart to help provide guidance.

My insights,

If you want to go fast with cast, use lighter bullets in the 300 or less weight range. Using gas checks you can approach jacket bullet performance, Shotgun powders have proven to be good choices for the high volume 45-70 case. They are easy to ignite and burn fully at lower pressures.

I shoot only plain base bullets in the 45-70, all of my own making. All are soft alloy with the max hardness of 25-1. A 260 gr plain base with shotrgun powder, Herco, at 1,600 fps is a tack driver with only 30-1 alloy. With a 540 gr paper patch using 40-1 alloy driven to the limits my shoulder can stand over a long string of shooting can perform well beyond my comfort levels. They performed at 1,600 fps which was OK for a hunting load where it is one and done.

In general, using cast bullets, faster powders will produce best results. Alliant Rel #7 is the slowest powder I have used that meets my accuracy standards with plain base cast bullets that do not use antimony to increase hardness. N-133 is slower than what I have found as effective. You need powders that burn completely at lower pressures with cast bullets.

You are obviously a reloader. The 45-70 cartridge is a great cartridge to use as a reason to start casting your own bullets! At the bottom of the links, there is a section for Cast Bullet References if interested.

load-data-and-references.628262
 

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Anneal the necks, don't resize completely, get a chronograph and try a faster powder.
Good advice here.

I size the whole case, but annealing will be necessary for the case to seal at the low pressure your load is developing. 40 grains IMR 4198 would get you in the 1650 fps ballpark, maybe a touch faster. I used a load with a CP 420 grain/IMR 4198 and the velocity was exactly 1650 fps.

VV powders are generally very clean-burning but your load is below where the powder is happy pressure-wise.

Though not totally necessary, a chronograph is a very useful tool that can tell you about where you're at in regards to pressure if you cross reference pressure-tested data.
 

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Discussion Starter · #20 ·
I tried crimping at the grove making them slightly longer than recomended coal, this with 46.5 grains made a much cleaner burn! This put me at 1,410 fps acording to a friends labradar. Done a new batch with 47.5 and 48 grains. Hopefully i'll be able to reach close to 1700 fps with my 18,5" barrel.

Thank you for all your insights!
 
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