Designing the 2-diameter paper patch bullet.

[Caprock]

Not a bad looking bullet. Its nice to see something with some dimensions attached to it. I am a little surprised to see such a blunt nose. I was thinking of a bullet with a nose radius of closer to 1". Does this bullet mirror that of the others you have been playing with?
I will be interested to hear how well it shoots. I am slowly gathering up stuff to move up to slicks. I have 2 rolls of paper on the way, 55Y and 55W. Was thinking of having Tom lengthen one of his bullets up to 1.25, http://www.accuratemolds.com/bullet_deta...355P-D.png , is the one I like the looks of best, but can be convinced in changing my mind by those that know better. My rifle has a 17 twist barrel and a greaser chamber.
Sam

I wanted a bullet that looked more like the old original rn Sharps and being more of a hunting bullet than anything long range. Tom won't make a true round nose or rounded snover,postell type....its gonna have a meplat. If thats what you want then Steve Brooks is the man to do a nose pour. If this works out i"m not not out a heck of a lot and will have Steve make me one. Betcha some of the others can project what this nose shape will or won't do. My twist is Shilohs 1-19

That 355P is a good looking bullet. Keep us posted.

[Distant Thunder]

I haven't worked with any thing in .44 caliber in many years and that was my .44-100 straight. Mine had a 1:18 twist and bullet length was always something that I had to watch closely. Even with the shorter lengths it never did well for me past 600 yards. I was able to get it to shoot paper patch bullets well.

The mold I used was of my own design and making. I don't remember the details now, but the mold is laying around here somewhere. It is a round nose and is a bore diameter design. I'll see if I can dig it up and find my notes. I do remember I had to use a grease cookie to get the best accuracy. It is possible that the right wad stack would have worked too.

that rifle had a grease groove chamber with a short, .150", freebore and if I had known then what I know now I would have made a 2-diameter bullet and I think that would have been a bit easier to make work and to load for in general. That rifle has been rebarreled and I am very happy with the new chambering, .22 LR. No chance I'll ever go back to .44!

As far as round nose designs go I'm very pleased with my .40 caliber 2-diameter paper patch bullet in my .40-65. I wanted a bullet as heavy as I could get in a bullet that would be stable in an 18-twist .40 and the old looking round nose design worked out well.

I really like my elliptical .45 caliber ppb for long range matches and it works very well, but I also like the looks of the old Sharps designs and they have performed well for me out to 600 yards. If fact I, for a few years back before ppb worked so well for me, used the Lyman 457125 Gov't bullet for my long range matches at 800 yards and it shot very well. I never shot it past 800 for fear it would fall out of the sky and land short! I often had the highest 2-day score at 800 yards when using it, so a RN can shoot well.

I think if you know your bullet and what it does in the wind a round nose can do very well. Where the elliptical will do better is when you miss a change in the wind, a pick up or let off or slight change in direction. That's when the elliptical will be moved less and save you some points. That makes them a better design. Assuming equal accuracy with the two.

[Kurt]

Arnie sent me some of his .40 hard alloyed DDEPP bullet and I shot them into the rest snow bank to see how that hard alloy obturate. I shot them in the .40-65 and the .40-70 both rifles have a standard chamber dimensions. I could not use these bullet in the .40-65 CPA rifle because it has a tight chamber for using the PP bullets only. His bullets won't even fit the fired cases shot from that rifle.
I was impressed the way they survived fired in the standard chamber. The only land cuts where on the expanded base diameter, no marked at all on the bore riding portion. The patched diameter was perfect that kept the bullet aligned perfect in the bore so there was no signs of runout or stripping in the narrow base band giving it full rotation.
Best of all there was no setback, the bullets are just as long fired as before being fired. Unfired they are 1.328" and recovered fired 1.328".
I don't think that hard of an alloy will obturate at or below bore diameter to make full contact in the grooves from what I'm looking at with these, but I might be wrong.........Kurt

   

[Kurt]

I went to the BIG town Rockford ILL. and found a new measuring stick and when I came home I looked on the snow pile again and found more of Arnies bullets and three of mine. Mine did not fair as well as Arnie's. All of Arnies are perfect shot with both regular chambers from the Browning and my Shiloh .40-70.
Last spring I started to use some thinner paper the 55Y and 55W that I feel is to thin for a .004" deep grooved rifle. Two layers only add .003" to the bullet and I always felt that is not enough. Well today I see that my suspicions are close to being right.
The three on the right are my bullets cast 1/16 T/L. I wanted to use this standard alloy that is still malioblle filling the grooves when they start moving.
What I found with these three bullets is a major amount of gas cuts that burned through the patches. Three for three strikes out in my book using this thin paper. Maybe a softer alloy might be the answer but I can't test this till next winter.

   

[Kenny Wasserburger]

I found this thread and read it all, excellent advice and observations, I kinda wish I had jumped into the Dual Diameter craze sooner. So far the bullet shows excellent promise vertical is on the order of 1.160 to 1.25 at 200 yards.

Load is 103 grs of Olde Eynsford and 110.8 grs of Goex Express which I just happen to have 1.5 cases left of that stuff. Rifle is my 25# Shiloh Dora with 1-16 twist. DD bullet runs 548 grs with 15-1 alloy 1.490 in length.

[Don McDowell]

Kenny that's the intesting thing with these dual diameter bullets, they work really really well, or they don't. Looking forward to seeing how that bullet treats you thru the season.

[Kenny Wasserburger]

Don the baptismal of fire will be in two week at Alliance.

Kenny

[Don McDowell]

Looking forward to it. I've got two pretty good loads to try and wring out for the 77 before then, if the weather cooperates.. If the weather doesn't cooperate I'm just going to toss a coin load 100 rounds and go.

[Distant Thunder]

Oh boy, that's a good looking bullet there!

I believe the 2-diameter design has a lot to offer and in most rifles will shoot with excellent accuracy as long as the diameters fit the chamber reasonably close or better said, as close as possible.

The design minimizes bullet upset in the case and freebore because the bullet already fit those areas closely before it's fired. Also, the bullet does not have to shorten as much as when it has to bump up to fill the case ID and freebore. The less lead that has to move around the better the accuracy potential.

Another thing the 2-D designs does is when it is seated in the case to a length that the groove diameter step is against the rifling leade it offer some initial resistance to bullet jump (caused y the primer detonation) giving a more consistent powder ignition and burn.

Recovered 2-D bullets look the same as recovered bore diameter bullets in that they are the same diameter for the length of the shank and all traces of the step are gone and the engraving is even the full length of the shank.

I will be watching for your match results, Kenny! Good luck to you!

[Semtav]

I just tested my 40-82 with its Dual Diameter bullet yesterday at 800 yds, the target was already shot up, but If I saw the hits accurately where I thought, it was more than impressive. Got to try it again on a clean target.