45-70 Load Data for Lyman 480 Grain Cast Bullet

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  • Last Post 20 May 2017
NH_Jim posted this 18 May 2017

Does anyone have tested reloading data for a 45-70 using the Lyman 480 grain bullet (Lyman Mould #2640658 Bullet #457658)?

It will be shot from a single shot break open model 1871 Wesson & Harrington (modern replica).

I have been using the published data for the 420 and 500 grain bullets.  I was interested in data specific to the 480 grain bullet.

 

 

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David Reiss posted this 18 May 2017

Jim,

I have checked some of my older Lyman manuals and can not find any loads specifically for the 480 gr. cb. I would continue to develope loads using 500 gr. data. 

David Reiss - NRA Life Member & PSC Range Member Retired Police Firearms Instructor/Armorer
-Services: Wars Fought, Uprisings Quelled, Bars Emptied, Revolutions Started, Tigers Tamed, Assassinations Plotted, Women Seduced, Governments Run, Gun Appraisals, Lost Treasure Found.
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onondaga posted this 18 May 2017

Jim,

The Lyman Cast Bullet Handbook #4 has a 45-70 Govt. load on p. 219 for a 475 gr #2 alloy RNGC Lyman bullet. The weight is closer to your bullet. Lyman shows IMR3031 as the most accurate powder selection: START 47.0 gr, 1657 fps, 32,400 CUP  -  MAXIMUM 53.0 gr+, 1802 fps, 38,500 CUP. Check your rifle maker for your rifle pressure rating. It is likely a lot higher as your rifle is designed to shoot modern Factory jacketed ammo.

The Lyman 457658 you have is pointed and gas checked and Original Schmittzer design for B.P.C.S. where a high ballistic coefficient is required. A very accurate bullet in most 45 caliber rifles (PB, SP, 480 - TP is 658). It should do fine with the Lyman load in your rifle.

 

 

Gary

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rmrix posted this 18 May 2017

The 457 658 I know about, is a plain base bullet.

Is it made as a gas check design too?

 

In BPCR rifles it has something of a poor reputation. Riflemen just getting into the game buy it thinking the pointy design will rule the field. At BP (trans-sonic)  velocity it is not any more slippery through air than other designs its same weight, Better accuracy and better Bc are found with other match bullet designs commonly in use today.

Perhaps driving it up into the velocity range that spitzer type bullets excel at, 1800 and up, would compete better, but the recoil would not be good. And as soon as the bullets drops back into 1700 - 1000 any advantage is lost. 

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onondaga posted this 18 May 2017

rmrix The source of my info on the mold is not from a bunch of internet ninnies and is accurate as I quoted from Lyman. Go here and scroll down (it's a lot of scrolling) to 457658:

http://ps-2.kev009.com/ohlandl/Cast_Bullet/Ideal-Lyman_Molds/Ideal-Lyman_Mold_Descriptions.html#308_mold

You see the bullet drawing with a pointed nose and a GC cut base along with the information I cut and pasted.

Gary

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rmrix posted this 18 May 2017

 



457658 Original Schmittzer design for B.P.C.S. where a high ballistic coefficient is required. A very accurate bullet in most 45 caliber rifles (PB, SP, 480 - TP is 658)

Gary, I'm not sure what to say other than the design is plain base.  And, Lyman's claim of High Bc does not hold in the tran-sonic velocity range that BP propels bullets ("Original Schmittzer design for B.P.C.S.") intended for BPCR matches.  In other words, the very pointy spitzer shape is a liability at the velocities it is used. The design is completely absent in NRA competition.

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onondaga posted this 18 May 2017

My picture wasn't as good as yours, YES it is a plain base. It would likely prefer H4895 reduced loads below transonic range, but that is not a rule and how it will perform in the OP's rifle  with 3031 and #2 alloy is for him to find out. The OP doesn't mention if he is a match shooter or not, he just bought an old mold that should fit his new rifle just fine. Of course if he is a Deer, Bear or Boar hunter, I'd recommend a flat nose like the RD design.

 

Gary

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rmrix posted this 18 May 2017


The Lyman 457658 you have is pointed and gas checked and Original Schmittzer design for B.P.C.S. where a high ballistic coefficient is required. A very accurate bullet in most 45 caliber rifles (PB, SP, 480 - TP is 658). It should do fine with the Lyman load in your rifle.

Gary

Actually, rather than using a poor picture, the clues are in the Lyman code text in your first post.

PB, SP, 480 - TP is 658

PB = Plain Base

SP is the nose

480 = weight in grains

TP is the number for the correct top punch

and 658, the last three numbers of the bullet, is the cherry

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NH_Jim posted this 19 May 2017

Many thanks to all who took the time to contribute to my post.
Additional details:
The bullet in question has a flat base.  Others have reported having a slightly different base for this mold.  It is possible that the mold number was reissued or that the mold is mislabeled.
Some Background to the question:
Curiously, the variance between alloys ranges from 355 to 507 grains.  Hence the reason I was looking for additional loading data.
It should be noted that the mass difference is not caused by casing errors such as voids.  A CT scan (X-ray computed tomography) indicates they are solid. Hacking the bullets into thin slices with a plasma cutter confirmed this.
But that is a topic for another day.

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Ken Campbell Iowa posted this 19 May 2017

just curious ... what alloys give you a 30 per cent mass variance ?? ...   also was there a dimension change ( as cast ) with the different alloys ?

thanks, ken

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NH_Jim posted this 19 May 2017

A variety of ingots added to the pot during batch production account for the running variance. Wheel Weight ingots have a large variance and frequently contain much more than Lead, Tin and Antimony.  The use of a mass spectrometer gives the exact composition of the alloy, but a mass spectrometer is a difficult tool to access! 

As an aside, the light weight bullets are hard relative to their lead alloy counterparts.  I do not have a good scientific way to non destructively measure the hardness yet. The 45-70 light alloy is very frangible upon impact. A topic for another day.

I did not notice a width change but that may be because I quench and age the bullets for a month and then size them.  I did not measure for a change in length but I may start.  The OAL of the cartridge was correct in the end. 

I considered writing an article for TFS but I don't know if there is any interest.

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beltfed posted this 20 May 2017

in my early experience at the BPCR game, I tried the 457658 Schmitzer.

It shot well, that is, until a head or tail wind during which it "took off like a kite". Of course, as said, I was shooting it at BP velocities in 1200fps area.

If you want to stay in that "under 500 gr" area for that H&R, take a look at the Lyman 457671 (GC Tan Ogive nose-nom 473 gr), or the 457406 (RNGC about 482 gr) Data for either from the LYman handbooks for the TD springfield will work. Pushing it for the '86 win loads- heavy recoil.  I would recommend one of these bullets over the 457658. I sold my Schmitzer mold!

beltfed/arnie 

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