What nose shape for 300-500yds?

[BrentD]

Flatsguide (bone fishing guide?) - your the prolate will be an excellent choice in your rifle, all the way to 1000 yds. Your bullet's length will be aoubt 1.46" or so. This mould from BACO will get the job done every time
http://www.buffaloarms.com/Bullet_Mo...px?TERM=Jim443. Load about 82 grs of Swiss 1.5fg and a 0.06" wad then compress to 0.1" below the case mouth (do not seat deeper than 0.1") and you are good to go to 1000.

If the bullets in your cases are too floppy after you set the bullet in them, you might try taking the depriming stem out of your FL sizing die and sizing the neck of the case. This is effectively a taper crimp and you should be able to get just enough crimp to barely hold on the bullet.

Bruce, My noses are not 2 calibers long - that would be 0.9"! I don't know anyone shooting noses that long. In fact, they are usually around 0.74" - or roughly 1/2 the length of most of my bullets.

This is my long range bullet. It has the 4:1:1 nose of about 0.74" but it is a little longer in the shank to be 1.51" overall and weighing 537 grs. However, this bullet it TOO LONG for an 18 twist. I use a 16 twist with this bullet.


The guy that made this mould only does them from time to time. Brooks has made a 1.46" long version for my 18 twist silhouette rifle. However, the BACO mould linked to above, is the easy way to fly. It is effectively the same bullet.

[flatsguide]

Hi Brent,
Yup, fly fishing guide in the Florida Keys for over 25 years. Bonefish ,Permit, Tarpon and sharks. 8 to 15 weight fly rods. It was a grand time.

[BrentD]

"was"? Sounds like a bunch of fun. last time I tried to fish the keys, I ended up in the hospital with a severely busted left arm.

Tarpon.... too cool.

[BRUCE MOULDS]

brent,
i'll have to restudy the formula for an ellipse!
this is why people with a cad programme are my friends.
keep safe,
bruce.

[BrentD]

Ah, the formula for an ellipse in three dimensions is an elegant thing. You can find it quickly on a wiki page actually.

In fact, the only reason I ever started shooting these bullets was because I could write the equation from memory. It was later that I found out there as a good theoretical reason for why it is a very good shape. As is often the case in nature, the simple elegant solutions are often the best. Of course, many others have been there before me, but at the time, no one was using truly elliptical bullets, but rather these things that were called ellipses with but had hemispherical tips. What's coming next will be a lot different - but very familiar nonetheless.

[BrentD]

https://en.wikipedia.org/wiki/Spheroid




Oblate on the left, prolate on the right:

[BRUCE MOULDS]

what's coming next, that is the question.
you have been dropping hints about such things recently.
please tell us more.
keep safe,
bruce.

[BrentD]

Well, I'm hoping it will be the ultimate and final bullet improvement possible in BPCR. But right now, all I have in a drawing, and a few bullets from a failed mould-making attempt. Another attempt is being made now and time will tell if it will work. I hope to shoot it in March. But until it is proven, I'll keep it to myself. I've been told so many times that nothing I ever did would work. So, I'll just keep the naysayers at bay for a while longer.

[Gunlaker]

Bruce, this wikipedia page is an interesting read when it comes to noses. You might find some nice ideas here.https://en.m.wikipedia.org/wiki/Nose_cone_design

Chris.

[BRUCE MOULDS]

thanks chris.
I have seen that before, but limited education equates to limited understanding.
possibly some of the power series might be like money/metford?
keep safe,
bruce.

[Gunlaker]

I think the chart at the bottom is interesting. I would imagine it'd be difficult to find a mold maker who would be willing to cut some of them.

One thing I've always thought about is that a carefully crafted shape will become a slightly different shape after bump up. If you wanted a bullet that was a prolate after bump up, you could probably model the deformation and then cut the mold with that taken into account. But that's a lot of effort.

If the current best bullet has an average BC of say 0.520 to 0.550 over the full trajectory, I wonder what the maximum possible would be for current twist rates.

Chris.

[Chill Wills]

One thing I've always thought about is that a carefully crafted shape will become a slightly different shape after bump up. Chris.

Bingo! - Hard bullets are needed for the high Bc designs. Many a spiffy design going in the chamber comes out looking very different with the accompanied low Bc and poor accuracy when cast too soft. Pb-Sn-Sb alloys are my friend. What others choose to do is of course, up to them.

[Gunlaker]

I think I'm going to experiment with one of Dan's antimony alloys this summer or fall. Not likely in the paper patched rifles, bu in my grease groove rifles.

A while back I bought a 14lb Borchardt in .45-2.4" but it has a long throated chamber. I have yet to do a chamber cast, but the freebore is something like 0.5" long! The case holds enough powder that I think it wants a pretty stiff alloy . It didn't like the Buffalo Arms 459535 Money bullet at 20:1, but doesn't mind a Creedmoor bullet with that alloy.

Chris.

[BrentD]

Chris, that will be a bastard to load for with a bore diameter bullet. I would go right to whatever diameter is necessary to fill that throat. I had a rifle like this too - only worse. I killed and elk with it, but that was the end of it - I rebarreled immediately thereafter.

[Gunlaker]

Brent I definitely won't try bore diameter PP bullets in that rifle . It's a really neat rifle, if you like Borchardts. It was originally a sporter in .45-2.1" and was reconfigured to look like the old long range Borchardt's, except with a heavy 32" barrel. I've only shot it twice since I bought it last christmas. It weighs about 14 lbs so even a heavy .45 cal bullet at 1350fps or so is comfortable to shoot.

I was dissapointed to see the long throat, but it was built by Curt Hardcastle ( and I think action and trigger work by Al Story ), so I imagine that the throat configuration is better than the old Farmingdale Shilohs. A .459" bullet seems to fill the throat but I need to cast the chamber to be sure. As long as the throat is a consistent 0.459" and the leade angle is reasonable I'll bet I can get it to shoot.

I find that most of my time is spent with three or four rifles that I'm taking to matches and spend little time with the others. I'd like to get this one shooting well enough to try it in competition, but we'll see.

Chris.

[Lead pot]

I think I'm going to experiment with one of Dan's antimony alloys this summer or fall. Not likely in the paper patched rifles, bu in my grease groove rifles.

Chris.

Chris.
A long time ago Dan T made a post on the Shiloh forum about using antimony, along this line, that it is poison for black powder accuracy. I disagreed with him saying that it was a plus for holding the ogive from getting set back and getting distorted and he went into one of his rages that extended into the PM's he sent to me. I still have them. but they will stay under. But I don't know what made him change his mind about the use of antimony.
Maybe he saw it in one of the old Lyman manuals. Lyman had more then #2 alloy they used to list. They had #1, #2, #3, #4, and #5 and 6 also.
But that is in the past.

Kurt

[BrentD]

Dan pretty much raged about everything that anyone did differently at one time or another. He used to rage at .45 calibers - all of them - and paper patched bullets too - also all of them. Yet, in the end, he was heavily into both and touting their advantages.

I have some lead plates, maybe 300#s of worth, that appear to have antimony in them. They test for hardness like Lyman #2 and they cast nice bullets but a slightly different texture of color to them than normal tin-lead, and the melt point and optimal casting temperature seem considerably lower than lead-tin.

Assuming this was Lyman #2 or darn close to it, what would one mix with it to get the equivalent of 16:1?

[jimofaz]

Brent,
Try adding 150% of Pb to your Lyman #2 alloy for a 16-1 equivalent. Example: 8 lbs. of 15 BHN Lyman #2 + 12 lbs. of pure lead for a 20 lb. batch of 11 BHN 16-1 equivalent alloy.
Jim

[.22-10-45]

Would a nose pour mould with the elliptical nose negate any advantage of said nose shape due to small cut-off flat on end of bullet?

[Gunlaker]

Dan was at one time using alloys with a very low percentage of antimony. Between 1.5 and 2 percent if I remember correctly. The alloy hardness was stable over time only if there was not more tin than animony in the alloy. I think the hardness was on par with 1:16, maybe a tiny bit more.

Mr. Rix has posted on these alloys a while back.

Chris.