Paper patching to bore or groove diameter?

[Distant Thunder]

http://historicshooting.com/mybb/showth ... p?tid=2619

This might answer a few questions on the basically three different paper patch bullet types in use.

I apologize if someone else has already posted the link, I don't have time right now to read all that has been posted. Looks like some good stuff though.

[semtav]

Wayne,
Since you were asking about the 45 degree step the 42-85 does have that step and you can see how far the paper sticks out. Don't remember what the leade angle is but it shoots equally as well as the others

[Kurt]

Ogive design has more influences on how a bullet performs with the ROT of the bore. A dual diameter has a advantage when it's used in a standard chamber design that excepts a groove diameter GG or PP. A Groove diameter PP in my opinion has a better chance of shooting well then one that is patched at bore because of a faster gas seal that helps keeping the vertical down. I find this anyway from my trials using a groove diameter PP bullet. I swaged and cast them both ways. Yes the groove diameter will take up powder space in calibers like the .45-70 or the smaller .40's but work great in the 2.4 or longer .45 cases.
Dan T put a lot of bullet drawings out in these forums and all were modern jacketed designs used in the HP rifles with a faster ROT then what we use in the black powder rifles and the jacket was replaced with lube grooves. Bullets of this design not pushed fast enough or increase the rate of twist have a tendency to give problems at ranges past 5-600 yards.

Bullets of the old designs like cast with this original Sharps mould have a ogive that is more forgiving and will stay stable at extended ranges even if there is not a good match between the length of the bullet and twist rate. Yes it might take a couple minutes more elevation but the holes through the paper will be round.

IMG_0207 by Kurt, on Flickr

Here is one of those sleek bullets I had Brooks make for my .44-2.6 (.44-100 Rem St) heavy barreled Shiloh that will put them on top of each other at close range but falls flat on it's face at 800 to 1000 yards using a 17 Rot but works fine in the 16 ROT 44-1/2 Stevens.

44-100 load developement by Kurt, on Flickr

This bullet will work at any distance your sights will reach patched at bore or groove

44-77 Sharps by Kurt, on Flickr

[rdnck]

You boys need to listen to Kurt. He gives good advice. Shoot straight, rdnck.

[Distant Thunder]

Kurt,

That last bullet looks a lot like my .40-65 bullet, which is a 2-diameter design due to the nearly .400" freebore in that rifle, and it shoots unbelievably well out to 600 yards. Supersonic designs do not work the best in our transonic velocity range.

For long-range shooting I don't think any design I've seen will do better under a wide variety of conditions than my .45 caliber Lodi bullet. I have used that bullet to win several long-range matches at Lodi in the past 9 years and place 2nd or 3rd in many more times. I think it has proven itself and has done so in two different rifles. One with a grease groove chamber and the other with a Danielson paper patch chamber. I have used only a bore diameter version but will be testing a 2-diameter design next year. I believe having a proper fit to the bore makes it so accurate and that the nose profile allows it to retain that accuracy in some pretty unsettling winds at long-range. Also it's length is well stabilized in the 18-twist of my rifles.

I am amazed at the number of people that use a bullet that skirts the maximum length that their twist can stabilize well and then choose a nose design that requires more spin than a velocity appropriate design of the same length would.

[Maj. Forrest Smith]

Hey, Kurt! Nice photo of the bullets out of the old mold for Paper Patching. I am curious in how the old shooters cut off the spruce lead and while I am at it, how do you cut it off? JG

[semtav]

Which bullet were you shooting at the 1000 a couple years ago Kurt ? or was that a GG bullet ?

[Kurt]

Which bullet were you shooting at the 1000 a couple years ago Kurt ? or was that a GG bullet ?

Brian if you mean the 2016 Mt 1000 I used two bullets and loads shooting the .45-2.4 Start of the match I used a BA MB with a Swiss load and I had a problem holding it on the first three with a 5-5-4 and I changed the load for the last target using a load of OE with the first bullet mould from BA when they first started making moulds and I spent time with Dave and Jim on the phone and I was after a slightly modified Metford bullet that is my more or less go to bullet for long range and it put 10 hits on the last target 11 with the sighter on the white or just on the edges of it with one sight change. I think they still have this bullet mould listed.

Here it is.

alloy test by Kurt, on Flickr

Maj.
Sorry for a little late reply. I just found my way home from the UP Michigan. I wanted to get lost but it didn't happen when the snow fell and I found my tracks in it to lead me back out

If you look at the mould you will see it has a nipper on the outer edge that is used to cut the sprue off. It cuts it very good to make it look like a sprue cut that as poured with a nose pour mould.

Kurt

[semtav]

Boy that looks surprisingly like the bullet I use in the 45's. Like to get one from you the next time you're up and stick in my mould to see where the differences are in the nose area.

[Kurt]

Brian when I ordered that mould the thick paper .0024" so I ordered the mould .442" and it has always shot well.

[mike herth]

Good discussion. I’m going to have 4 months to ponder all this while roasting in Arizona.

1. What exactly is “throat”? The distance between the end of the freebore (or end of chamber if no freebore) and the beginning of the leade (the transition cut into the lands)?
2. What is the most desirable nose shape for 45 caliber at 1,000 yards for PP bullet?
3. What is the most desirable length of bullet shank and ogive for long range?
4. What is the most desirable length of bullet given the above criteria in 16” ROT barrel?

With all the “testing” going on I’m hoping there is some general concurrence in this. Your indulgence is appreciated in my understanding of these variables.
Mike

I think Brent has posted a sketch addressing #1 but I am not finding it again.

[ian45662]

So I guess someone is going to have to explain to me how to post pictures in this forum. I can post stuff on Facebook real easy but I’m not familiar with this format. Do I need a photobucket account? If I do I will get one but I will post a pic of my chamber cast
And the bullet. I am shooting an elliptical bullet out of a 16 twist green mountain barrel in my c sharps highwall. It drops out of the mould at .445-.446. My Seth Cole 55w paper brings the finished diameter to .450ish with the wet patch method. The bullet itself is 1.51” long. Weighs in at 536 grains when an alloy of 14:1 is used. I said elliptical but I reall call it Brent’s bullet. It has treated me very well over the past couple of years in bpcr silhouette.

[ian45662]

[TexasMac]

What exactly is “throat”? The distance between the end of the freebore (or end of chamber if no freebore) and the beginning of the leade (the transition cut into the lands)?

My definition of throat, which is also used by many writers and firearm glossaries, includes the section that starts at the beginning of the chamber transition and ends when the lands are at full height. Therefore, the throat includes the chamber transition (D), freebore if it exists (F), the transition region from the freebore to leade (freebore transition or FT) and the leade (G). Below is an example of the Browning .40-65 & 45-90 chambers. BTW, For clarity, rifling is shown without a twist.

Wayne

[mike herth]

Thanks Wayne, very helpful.