As far as a boolit shape I've always fond the truncated cone to be rather odd looking. I'm not knocking it mind you I've got a Makarov that prefers them to a RN. But what advantage was the design to have over any other style?
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As far as a boolit shape I've always fond the truncated cone to be rather odd looking. I'm not knocking it mind you I've got a Makarov that prefers them to a RN. But what advantage was the design to have over any other style?
If you don't have the time to do it right, when are you going to find the time to fix it?
It moves the center of gravity and the center of pressure farther to the front of the boolit. It also creates a flat meplat which would displace water/tissue more readily than a round nose.
Old enough to know better, young enough to do it anyway!
Men who don't understand women fall into two categories: bachelors and husbands!
The truncated cone has the advantage of being just like a semi wadcutter in that it removes (unsupported) nose weight on the front half of the bullet maximizing bearing length with equal weight bullets.
The advantage that it has over a semiwadcutter is that there is lead in front of the band to support the front band from colapsing and flowing forward upon impact with the forcing cone. Theoretically the band (bullet) can be softer or not need as wide of a front band as a semiwadcutter of the same weight to perform. In comparrison, the strongest design to resist impact is of coarse the olgival, but it is difficult to get the bearing length to hold the nose center in the bore with lighter weights. Which is why you will read Veral of LBT telling you that his designs work best in the heavier weights and driven to the highest velocities. (harder to stabilize)
Those two types of designs provide for the longest bearing areas per weight of any other design at the expense of case capacity up to some weight cut off point in each bore diameter. The longer bearing area can also help with case neck tension too if the reloader is running lower powered loads. So the advantage for trunes is with lighter to mid range weights. And in handguns with slight misalignment that would otherwise affect a semiwadcutter.
Reading can provide limited education because only shooting provides YOUR answers as you tie everything together for THAT gun. The better the gun, the less you have to know / do & the more flexibility you have to achieve success.
They feed well in autos.----dale
When used in speeloader for revolvers they drop in slicker than anything else. IME
Paul G.
Once I was young, now I am old and in between went by way to fast.
The end move in politics is always to pick up a gun.
-- R. Buckminster Fuller
All kinds of theories! Drive length, weight forward, weight rearward, and on and on. I don't believe in any of it.
What counts is alignment in the forcing cone and reduction of boolit damage before it enters the bore.
When you search for pure accuracy from revolvers like I do, you soon find what works and in no case at any time do I get the accuracy I demand with a Keith.
Here is a picture of a 265 gr RD, .44, next to a 245 gr Keith. Drive bands and length are only .010" different between the two but there will be a little engraving on the back of the ogive of the RD, so it adds a little to the drive area. Both use the exact same powder charge for best accuracy, yet the RD has shot 1/4" at 50 and holds 1" to 1-1/4" at 100. The Keith is lucky to get 2" to 3" at 50.
Let's move to the .475 boolits. Here is a 325 gr truncated cone next to a 375 gr Keith HP, notice the vast difference in drive length.
Then there are two 400 gr boolits, an LBT and a Keith.
In both cases, the truncated cone will poke one ragged hole at 50 yet the Keith is still lucky to shoot 2".
So we run the range of short, long, HP, solid, light and heavy, yet the truncated cone always shoots best.
You can beat yourself up thinking up theories and how much weight you need front to rear or how much drive band length is needed and you will get nowhere because it just means nothing. Match the boolit length and velocity for each length to the twist and you will find the truncated cone is the best boolit shape ever designed and it does not matter if it is a WLN, WFN, Lee or LBT.
Last edited by 44man; 10-31-2009 at 09:51 AM.
In the cases of molds made with cherries it is probably easier to grind a cherry than many other nose designs, and it does feed well in semi-auto's.
Bill
Both ends WHAT a player
Ah! Well done Grasshoppa!Originally Posted by 44man
I have said it over and over......EMPIRICAL evidence.....seeing/experiencing what works and accepting the results, regardless of theories, is ALL THAT MATTERS!
I'm shufflin' thru the Texas sand..... but my head's in Mississippi
hmm, speed loaders, hadn't thought of that! I may need to get one!
Same here. I have all these RN moulds for my speedloaders and never thought of TC boolits.
Damned if you don't learn something new. . .
--44Man, VERY well said and thanks for the info and comparisons.
+1
They are accurate for me as well
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Great job!!! Except for one small detail. Your theory has one slight hole in it.
Not a single design that you show in the photos is a true truncated cone design. Those are all Secants which is a hybrid truncated cone and olgival design.
Reading can provide limited education because only shooting provides YOUR answers as you tie everything together for THAT gun. The better the gun, the less you have to know / do & the more flexibility you have to achieve success.
From my shooting experience with the Keith style and the Truncated Cone, so far the Truncated cone is more accurate than the Keith.The truncated cone will poke one ragged hole at 50 yet the Keith is still lucky to shoot 2".
I like a boolit that with its diameter just past the ogive that will be started into the throats. This helps with alignment. Actually the boolit will be aligned perfectly with the throat and barrel like this. If I could get the front driving band of a Keith into the throat without the nose of the boolit sticking past the end of the cylinder then I think accuracy would improve.
If the boolit isn’t resting into the throat then it is laying in the chamber. A boolit then has to align itself with the cylinder throat when fired.
For instance, the 358429 (Keith Style) front driving band almost reaches the throat entrance of my GP-100 throats. I can chamber a 358429 and still wiggle the nose of the boolit just a little bit while holding the boolit all the way in the chamber with my thumb.
I was on the GB for the 44-444. The 44-444 is a secant ogive. The boolits are sized to the chamber dimensions of my 629 which has been reamed to .430". When I chamber one the same way as my GP-100 the boolit doesn’t have any wiggle to it. Part of the boolit past the ogive is resting in the throat, thus the boolit is perfectly aligned with the throat and barrel. I have experienced superb accuracy with this boolit although I’ve just started testing it and working up loads. Another thing, I’ve experienced zero leading, I mean zero with this boolit with the couple different loads I’ve tried so far.
If any of this makes sense. Just my .02 worth.
Last edited by Down South; 07-30-2009 at 11:27 PM.
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Samuel Adams
Sam
Feeding in semiautos and meplat for better tissue cutting than RN.
Bill
If it was easy, anybody could do it.
I have the Saeco 220gr TC GC for the 41 mag. Very accurate bullet. Don't know how it would perform on elk with the small meplat.
I have also found the TC design is a very easy on to cast good bullets with.
Does not matter like I said, get rid of the nose that is too small for the bore and the shoulder, then the boolit will follow the forcing cone into the bore.Great job!!! Except for one small detail. Your theory has one slight hole in it.
Not a single design that you show in the photos is a true truncated cone design. Those are all Secants which is a hybrid truncated cone and olgival design.
I have every kind of nose you can think of on my molds yet the Keith is the only style that gives me trouble.
With the few thousandths play in a cylinder, the boolit will turn the cylinder to align. Something the little shoulder on a Keith can't do, it just mashes on one side.
I do not believe in a dead solid cylinder lockup, they give me the most problems with accuracy and have to be dead on perfect to the bore. One out of 100 might be right but the rest are to show friends how tight the gun locks up!
When I cut a cherry, I pre-cut the nose and use a file until I like the shape. I could care less what the shape is called, they all shoot and nobody has shown accuracy like I get from so many different revolvers and boolits on any site.
You can't pick apart
results.
My 330 gr .44 boolit has a true truncated cone cut as close to the forcing cone angle that I could get it. You seen the group at 200 yards that measured 1-5/16".
Yeah, some believe in making a boolit soft so it mashes all out of shape, then reforms to the bore and I have to ask why the guy was so picky to buy a certain mold and boolit design? Why worry about grease groove shape? What difference does a nose shape make when it slumps?
Here is a recovered Lyman boolit from my .45 I found on the ground after going through a pile of steel belted tires. Other then the rubber on it, do you notice anything strange???
It still looks like the boolit I cast! Even the GC is still on.
This boolit has done 1" at 75 yards from my Vaquero and will go through a 16" tree and 5 deer!
Bass, you have NEVER proven me wrong yet.
Picture didn't take, try again. My mouse double clicks on me.
Last edited by 44man; 10-31-2009 at 09:51 AM.
That Lyman is the boolit that does this at 50 yards Bass. I have dropped deer in their tracks at 100 yards and my last deer with it was 76 yards, all off hand. Many have fallen to it.
No, it is NOT a truncated cone but it is also not a Keith. I have a good slingshot for a Keith though.
By the way, that is 5 shots!
Last edited by 44man; 10-31-2009 at 09:51 AM.
You cast a real good duplication of a FMJ........................
True, that is what it takes in a revolver. But a ductile boolit also shoots as long as it is tough enough.
I shoot a wide range of alloys and as long as they resist deformation, they are good to go.
It is amazing how far you can go and still get accuracy but air cooled or dead soft alloys are out if you want to hit anything.
Even an under size boolit that is started straight and does not deform will shoot as long as it is groove to groove size or a little over. It is better if it fits the throats but is not as critical as some think.
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