Bullet design for 1000 yds with a 45-70

[XTR]

I'm about to start trying to work up to shooting to 1000 yds with a C.Sharps 45-70 (30"). I belong to ORSA and compete in 1000 yards shoots in F-TR now, but obviously slinging a 500+gr cast bullet at barely supersonic speeds is a little different than shooting Berger 185LRBT at close to 2800fps.

I've read a number of things about using GG bullets cast with the front driving bands reduced to bore dia to allow longer seating thus more powder to get to 45-90 level MVs. There are a couple of designs out there to allow this kind of seating, one has the usual number of grooves with the first two just not as deep, the other that I've seen is the NASA mold like the one from BACO with only 2 grooves. I understand the idea of an improved BC without the grooves, but does this bullet carry enough lube for match shooting? Has anyone seen any real world improvement in windage/elevation with these.

[Red Sky]

Not sure about the longer seating, but do you really need it? I doubt the velocity gain is going to put it into a different ballistic "category" and you're going to have a lot of drop regardless. I'm fairly certain the microgroove designs tend to have higher BCs, both from the posted numbers from various sources and the raw aerodynamics.

More or less grooves will have less effect than the size and depth of them simply due to the nature of subsonic airflow (supersonic will benefit from less grooves due to shockwave formation, but which is more important to you will of course depend on the proportion of each regime during the flight time. The smaller micro lube grooves will create less disturbance in either flow regime - easily visualized by small "eddy currents" of air being sucked into the low pressure pockets that form inside those grooves during flight (due to the Bernoulli effect of the passing air), which causes additional drag. This same phenomenon is also why boattail designs have higher BCs than otherwise similar shapes. Obviously the number will have an effect as well, but after the first groove the airflow is already detached and disrupted, creating less suction from Bernoulli effect and therefore less drag on subsequent grooves.

Honestly, I would just fling a heavy boolit with likewise high BC at whatever velocity you comfortably can (should be able to get 1500 fps or so with the right loads I would think) and have enough elevation adjustment to handle it, which probably involves a vernier sight (?).

I can't say I have any experience whatsoever with that type of shooting, so I may be answering a question you didn't really ask. If so, I apologize. I just figured I'd chime in on the aerodynamics as that is my area of study at school currently. I may be incorrect about which effect dominates between number and size of grooves as I obviously don't have any numbers to work with, so consider the above a basic, qualitative argument and ignore it if real evidence otherwise exists. Good luck!

[Bullshop]

I was recently shooting a Trapdoor at 1000 yards. Nothing formal just fun shooting. I was shooting a Saeco 530gn multi groove boolit and a smooth paper patch boolit of roughly the same weight. Both were loaded with 21gn 2400 powder and a packing popcorn filler.
Both loads were in running about 1270 fps or very close to it.
When I got on the 1000 yard gong with the groove boolit the smooth PP would hit several feet high. When on with the PP the groove boolit hit several feet low.
I think those results may have some bearing on your questioning. It surely surprised me.
I think there will be a benifit to wind drift with the smooth boolit as well. I had no cross wind on that day so have nothing to compair.

[XTR]

I am a full and hearty believer that MV is temporary and BC is forever. I won't bore you with the details but the 308 F-TR world has moved from zippy 155s cranked out at over 3K to 200s starting at about 2600 all in the name of windage. I've experimented with 3 different bullets in the 175 to 185 class and know the differences in all three. I'm not surprised that the slick PP bullets get there with less elevation. I'm kind of wondering if anyone who shoots at Whittington has first hand knowledge. Honestly, molds, even custom ones are pretty cheap compared to the $47/100 I spend now on Bergers (I fired over 1500 this yr in practice and competition) so I'll probably just get a couple and experiment for meself. I have access to the 1000 yard line anytime we're not having a match, the problem is usually finding a puller.

[MT Chambers]

I have the molds like the OP talks about, they are "badger" designs, spitzers with smaller bore riding front grooves, and yes, they do allow alot more powder in your case, very accurate as well. I have them in .45 and .50 cal...made by NEI molds.

[Bullshop]

Also available from Buffalo arms is a copy of the Lyman Postell at about 530gn. It has the reduced diameter front driving bands. They claim they are made in house. I have the mold and it is a good quality mold.
I would also mention getting good service from them when they seent me a mold that was dropping undersize diameter. They claim .459" with specified alloy but mine was undersize.
I sent it back for thier inspection and they confirmed and sent a new mold.
The person I dealt with said that two of those molds left the factory and I was lucky #2
Esentially it allows 45/90 volume with a 45/70 case.

[XTR]

Also available from Buffalo arms is a copy of the Lyman Postell at about 530gn. It has the reduced diameter front driving bands. They claim they are made in house. I have the mold and it is a good quality mold.
I would also mention getting good service from them when they seent me a mold that was dropping undersize diameter. They claim .459" with specified alloy but mine was undersize.
I sent it back for thier inspection and they confirmed and sent a new mold.
The person I dealt with said that two of those molds left the factory and I was lucky #2
Esentially it allows 45/90 volume with a 45/70 case.

I've been looking at the Postell, the money bullet with the reduced first band and the NASA bullet. I was just wondering if anyone has first hand experience with any of them.

[montana_charlie]

I've been looking at the Postell, the money bullet with the reduced first band and the NASA bullet. I was just wondering if anyone has first hand experience with any of them.
The Money bullet got it's name when a new bullet design was being used in serious competition by Keith 'Doc' Lay. (I don't know the man, but I know the name)

The design was the result of independent work by Dan Theodore, but (just like all roads lead to Rome) his experiments led him to almost the exact same place where Metford arrived when searching for the best bullet for the #2 Musket cartridge used in the Martini by the British.
The two bullets are not identical, but the nose shapes are very similar.

Theodore's design had the two front bands reduced so that it could be set out far enough to get a powder charge in a 45/70 case that would generate 1300 - 1350 fps of muzzle velocity. This is because the best ballistic coefficient for the bullet is realized at that speed.

Doc used the bullet in a rifle that he had always called his "Money Gun'. When his match results became known, everybody wanted a mould which cast that bullet. Needing a term to call it by, 'Money bullet' just got stuck on it.

The Money nose has been used on a number of shanks, but if you want a grease grooved bullet, expressly set up for long range 45/70 shooting, the "Doc Lay Money Bullet" is a good prospect.
Paul Jones will know what you mean if you ask for that mould cavity because he cut the original for Doc Lay.

If you want to know details about the dimensions ...

http://i684.photobucket.com/albums/vv203/montana_charlie/Docs45-cal18-TMiniG5-groovetappered.jpg

CM

[gray wolf]

Lyman used to make one, I think it was called a Winthworth or wintworth
Nice long multi grease groove with a SWC type front end. Did very well in my BP rifle.
Just saying

[Wally]

Lee offers one---# 90577.....500 grain 3 Radius ogive..must be awesome to shoot at 1,000 yards with its' BC of .443

[montana_charlie]

Lyman used to make one, I think it was called a Winthworth or wintworth
Nice long multi grease groove with a SWC type front end. Did very well in my BP rifle.
Just saying
Yeah, that's the 457121PH Whitworth bullet, intended for use in the Whitworth rifle, a percussion muzzleloader with polygonal rifling.
Probably has a BC of about .3 or less

http://images1.opticsplanet.com/755-405-ffffff/opplanet-lyman-black-powder-bullet-mould-45-whitworth-457121ph-2641121.jpg

Just sayin' ...


Lee offers one---# 90577.....500 grain 3 Radius ogive..must be awesome to shoot at 1,000 yards with its' BC of .443
You don't see many commenting on the Lee bullet in discussions about long range shooting, but the few remarks I have seen said it loses it's sense of direction well before it gets to 800 yards.

The Money bullet BC is said to be .571 at 1300 fps.

CM

[Idaho Sharpshooter]

Easy Answer: look at the Top Twenty Equipment Lists.

[hydraulic]

At age 75 I have no presumptions of shooting in the class of Doc Lay, who, incidentally, won the Quigley in 2010, while I shot 219th of 625 shooters, and who was just down the line from me this year when the Ballard tragedy happened. Anyway, that match is only 800 yds. maximum, but I also shoot twice a year at Alliance which has a 1000 yd. range. Harlan Sage runs that shoot in August, and he gave me some good advice when I first started BPCR shooting 5 yrs. ago. He said to develop a load that shoots well in your rifle, and then quit chasing loads, bullets, lubes, etc., and spend your effort in trigger time.
I have a Shiloh LRE in .45-70 and I shoot the RCBS 82084 530 gr. bullet
cast from wheel weights over 70 grs. of KIK 2f compressed .250 with a oatmeal box wad and Emmets lube. As I mentioned above, I'm not an expert at this, but I shoot fairly well for an old man- not anywhere near the scores of Doc Lay, Wasserburger, or Linda Clendenan, and I do it the simpliest way I can. I also get out to my range and put 20 rds. through the paper two or three times a week.

[XTR]

Charlie, I've kind of had my eye on the Money Bullet, whether it's one from BACO or from Paul Jones, from what I'm reading it seems to be about the best nose design out there in cast lead long range work.

What's the latest "tech" at the 1000 yard line? I can see the obvious BC advantage to a PP bullet, but are guys using them, or does having to wipe every shot slow you down too much? As I alluded to above, I shoot F-TR. I went to Raton this yr, I didn't get close to a national title but I did bring home a gold. I understand putting shots on target while you have the wind. Does wiping slow you down so much that you have to make a whole new wind call for each shot?

Are PP bullets as accurate as the GGs?


I've seen some recent pictures from Lodi, looks like there are a few people wiping but most are using tubes.

[cajun shooter]

You need to PM Don McDowell of this forum. Don and his sons have eons of time doing what you are about to try.
Kenny Wasserburger who is also a member of this forum holds HRA records at Raton and is one of the best shooters going.
These and others like Dan Theodore are some of the best.
I use the Saeco 535 grain bullet from the Saeco 745 mould.
You should also check with the man who puts on the Quigley at his online store, Sage Outfitters. They sell some very nice bullets for the BPCR shooters at very good prices.
The book by Mike Venturino, Shooting Buffalo Rifles of The Old West also gives some great information from all of the top shooters. The book by Mike and Steve Garbe, The Primer also is full of information.
If all of these sources are not enough to overwhelm you then contact Dave Gullo of Buffalo Arms.
The wealth of sources are there for the taking, all you have to do is read and believe.

[montana_charlie]

Charlie, I've kind of had my eye on the Money Bullet, whether it's one from BACO or from Paul Jones, from what I'm reading it seems to be about the best nose design out there in cast lead long range work.

What's the latest "tech" at the 1000 yard line? I can see the obvious BC advantage to a PP bullet, but are guys using them, or does having to wipe every shot slow you down too much?
I don't shoot in matches, so I can tell you the 'history' of a bullet, but I can't provide insight on time constraints in a match environment.
Guys who shoot PP and wipe between shots DO shoot in matches. That's all I know, for sure.

A discussion about four months ago talked about the Money moulds from BACO as ooposed to the Money moulds from other sources ... such as Paul Jones.
It was the opinion of some that the BACO moulds have a smaller 'tip radius' than the original Money bullet design.

The problem with that controversy is that when you look at diagrams drawn by Dan Theodore - which depict slight variations in the shanks for particular applications - the diameter of the 'nose sphere' might be .250" or .225".
The 'Doc Lay' bullet - the 'original Money bullet' - has the .250" tip, so I think of that as the 'correct' dimension.

I have never been able to determine why the difference exists, and Dan has never specifically answered that question for me.

Anyway, perhaps BACO settled on the .225" tip when they set up their lathe to cut the nose of the cavity.

I see that you have Dan Theodore (himself) answering your questions on the other website, so I won't say any more unless you have specific questions for me.

CM

[XTR]

Thanks for the feedback.

[XTR]

Easy Answer: look at the Top Twenty Equipment Lists.

Where do I find that info? My google-fu (ok, I use Bing so Bing-fu) has failed me. The info on BPCR.net hasn't been updated since 2010. If you looked at the F-TR info from two yrs ago you'd see a very different list than if you compiled one from this yr at Raton. I know that the BPCR has been around for a century and a half or so, but I'm curious as to what's working.

[45 2.1]

I see that you have Dan Theodore (himself) answering your questions on the other website, so I won't say any more unless you have specific questions for me. CM

Charlie............ is the money bullet copyrighted or is it a free design? The reason for the different noses is that not too many people can actually figure the correct radius for a tangential radius on the 0.250" diameter nose.

[montana_charlie]

Charlie............ is the money bullet copyrighted or is it a free design?
I can't give you a 'legally' accurate answer. I simply don't know.
I have a mould for a Money bullet which was produced by a mould maker who (I am sure) did not obtain a license from Dan Theodore. But, perhaps BACO has worked through some kind of deal in that regard. The same would be required from Paul Jones and Steve Brooks, I guess, but I haven't heard any talk of such things.


The reason for the different noses is that not too many people can actually figure the correct radius for a tangential radius on the 0.250" diameter nose.
Well, I'm not a math genius, and certainly no machinist. But, with a scale drawing on a large sheet of paper - plus a pencil and a ruler - I was able to determine that ogive radius by trial and error in about four attempts.

Since I didn't use any calculations to derive a target number, I think it's possible, when relying on trial and error, to accomodate either tip diameter with equal ease.

As I recall the ogive radius was very close to four times the caliber.

CM

[hydraulic]

cajun;

You got mixed up there a little. Harlan Sage of Sage Outfitters sponsors a shoot at Alliance, Nebraska. Al Hill, owner of the ranch where the Quigley is held sponsors that shoot.

[Tom Myers]

Well, I'm not a math genius, and certainly no machinist. But, with a scale drawing on a large sheet of paper - plus a pencil and a ruler - I was able to determine that ogive radius by trial and error in about four attempts.

Since I didn't use any calculations to derive a target number, I think it's possible, when relying on trial and error, to accomodate either tip diameter with equal ease.

As I recall the ogive radius was very close to four times the caliber.

CM

Charley,

The radius is 1.828" (4.0625 times the nose diameter).
Actually, it takes a LOT of calculations to tailor the ogive length, meplate diameter and tip length to fit a certain ball diameter into the specified nose length. I worked out the algorithms for the soon-to-be-released Bullet Design Professional software and this is what it came up with

http://www.tmtpages.com/LinkSkyImages/DT%20Designs/DT_Design_459-450-525_MB_535_gr_OgiveCalc.Jpg

http://www.tmtpages.com/LinkSkyImages/DT%20Designs/DT_Design_459-450-535_MB_535_gr_Sketch.Jpg

[Tom Myers]

Charley,
The radius is 1.828" (4.0625 times the nose diameter).
Actually, it takes a LOT of calculations to tailor the ogive length, meplate diameter and tip length to fit a certain ball diameter into the specified nose length.

Having said that, if the dimensions of a tangent ogive are known, the radius can be found by a fairly simple calculation.

The dimensions of a Tangent Ogive may be defined by 4 dimensions: The radius of the curve, the length of the nose, the base diameter and the tip diameter. If any three of the dimensions are known, the fourth may be calculated using variations of the following formula.

R = ( L x L ) / ( D – T ) + ( D – T ) / 4
R1 = ( L x L )
R2 = R1 / ( D – T )
R = R2 + ( D – T ) / 4

Where:
R = the Radius of the curve.
L = the Length of the ogive. (do not include the length of a round tip)
D = the Diameter of the nose .
T = The diameter of the Tip or meplate.

In this case:

L = 0.6172
D = 0.4500
T = 0.2353

( L x L ) = 0.3809
( D - T ) = 0.2147
( D - T ) / 4 = 0.0537

R = (LxL) / (D-T) + (D-T)/4 = 0.3809 / 0.2147 + 0.0537 = 1.828.

The Radius is 1.828 inches.

Expressing the Radius in nose diameters:
R / D = 1.828 / 0.450 = 4.062 diameters

Re-arranging the terms in the formula to find each of the dimensions from the other three.

L = Square Root( R * ( D - T ) - ( D - T ) x ( D - T ) / 4 )
L1 = ( D - T ) x ( D - T )
L2 = L1 / 4
L3 = R * ( D - T ) - L2
L = Square Root of ( L3 )

T = D - 2 * R + Square Root( 4 * ( ( R x R ) - ( L x L ) )
T1 = ( R x R ) - ( L x L )
T2 = Square Root of ( T1 * 4)
T = D - 2 * R + T2

D = T + 2 * R - Square Root ( 4 * ( ( R x R) - ( L x L ) )
D1 = ( R x R ) - ( L x L )
D2 = Square Root of ( D1 * 4)
D = T + 2 * R - D2

These procedures are explained with reference to a diagram on my website at this link

Tangent Ogive Calculations (http://www.tmtpages.com/tech/tangent_ogive.htm)

Hope this helps.

[cajun shooter]

Yes, I did and knew that after I had posted, Harlan is a good man and knows his stuff still the same. It also appeared that none of my posting was going to be looked at so I decided to just let it go as I knew someone would post the correct info.
I've never met Harlan but he has helped me on several different shooting projects. Thanks for catching my slip up. Later David

[montana_charlie]

Pretty neat software, Tom.
But then, I'm a sucker for clear diagrams, no matter how they get created.

CM

[XTR]

What alloys give the best results in this application, assuming a 535 Postell or Money bullet? And is the answer pretty much the same in both a PP and GG bullet?

[Whiterabbit]

I want to up this. There's some GREAT discussion on greasegroove design and driving band design. Not much on the nose.

Why not a small but flat meplat?

How much bore ride is needed?

ratio of base to crimp and nose to crimp.... does it make a difference (in flight)?

Looking at the money bullet:

Bore ride is .25 calibers and nose is 1.5 calibers. If I wanted to maintain the 1.5 caliber nose, does the profile matter? Obviously at some point I thin it out too much and get nose slump. What's a safe range of ogive radius to use to allow me some meplat (.2-.3) without the worry of slump?

Would a .2 meplat kill me? Most BPCR bullets are RN but the Hoch's are flat nosed. Of course, they are much smaller than .2!

Finally, location of the theoretical crimp grove changes the relative spacing of center of gravity to center of pressure. is this something I can ignore, as long as the nose, bore ride, driving bands, and grease grooves are in good shape?

[Rattus58]

Lyman used to make one, I think it was called a Winthworth or wintworth
Nice long multi grease groove with a SWC type front end. Did very well in my BP rifle.
Just saying

Whitworth... and for the 45-70 the 457121 is probably what you're talking about. I use this in my .451/.458 bore 45's.

[Whiterabbit]

OK, I re-read post #23, that simplifies my questions.... alot.

Right down the the "ideal" meplat, and "what I can get away with"

So, I want it small enough to get me increased length and therefore good BC. But I want it big enough so there's no nose slump. I'm looking at .2-.3 inches. Should I be looking at teh big or small side of that in particular? cant go wrong anywhere in there with a nose length of 1.5 calibers? (about .6")

Also whether or not I have to really worry about CG and CP

[Whiterabbit]

drew up a couple examples.

It's a 45 cal, but I only have access to mountain molds site so I am limited as to what I can produce. The actual weight ends up being around 750 grains, so I have to scale everything 75% to make it work. Interested in folks thoughts. On the nitty gritty design, not on the merits of such a heavy bullet or whether it will work for the firearm or not (in concept, it will).

same bullet, just with and without crimp groove (I dont need to crimp)

http://castboolits.gunloads.com/attachment.php?attachmentid=71355&d=1369328344

http://castboolits.gunloads.com/attachment.php?attachmentid=71354&d=1369328341

highlights:
60%/40% body to nose
big driving band in the front and back
30% of the nose is bore ride
.2" meplat (accurate molds friendly)
bore ride is to be tapered from bore ride diameter up to body diameter
wide shallow lube grooves (copy old west bullet mold design)
any actual dimension wanted, just divide the number by .75

critiques? any of you guys see any "gotchas"?

(I did not anticipate how much fun bullet design is.)