doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Pattern theory

Pattern theory involves Pachinko fizzicks as Oberfell & Thompson realized long before anyone came up with PAM, which was predated by LDA [Latent Dirichlet Allocation], but still well after the penultimate werk done in Oklahoma by a couple of guys having a lot of fun earning their doctorates.

IOW, rather than get into a Bayesian inference or getting into the posterior of distribution, hard data remains vague, but one can recognize the footprint easily enough .. on a grease plate.

He called a bs flag, fine, but only Stan provided sources to investigate.
Not a data source, just more opinions.

It is a proven fact as far as I'm concerned, that a single lead bullets' nose will deform back towards the base on firing, and the nose will show deformation after it clears the muzzle even though it didn't touch some wad material, other shot or the barrel.
Maybe at light speed as a near plasma
Why wouldn't the leading surface of a perfect sphere deform back to some degree of out of round.
Maybe at light speed as a near plasma
It is a fact that the larger the lead pellet being employed, the lower the antimonial content needs to be for that pellet to have the same degree of resistance to deformation as a lead pellet of a smaller diameter.
No - lead has the same resistance to deformation regardless of shape or size but a larger pellet will suffer less surface AREA deformation as a consequence of GREATER SURFACE AREA in relation to contact area with other pellets

By the same token a shot load with a long shot column has more resistance per square inch to being moved than does a shorter column.

Just back from Hogwarts refresher course? I'll bet you think that somehow influences inertia. So two objects of the same material and same mass but different shapes will resist acceleration at different rates. I think that violates all three of Newton's Laws of Motion

I realize that the shot string (cloud) is moving fast, but it is not that fast that the targets speed is negated completely. The pictures in Brister's book clearly show this.
Yes it is. No they don't. Not running down Brister - he tried. If you care to calculate how long it takes for a shot string to pass a given point and how far a target moves in that time guess what happens?

tw - "Pattern theory involves Pachinko fizzicks as Oberfell & Thompson realized long before anyone came up with PAM, which was predated by LDA [Latent Dirichlet Allocation], but still well after the penultimate werk done in Oklahoma by a couple of guys having a lot of fun earning their doctorates.

IOW, rather than get into a Bayesian inference or getting into the posterior of distribution, hard data remains vague, but one can recognize the footprint easily enough .. on a grease plate."

At last, a cogent comment. Tip o'the hat to tw

'bout it for me thanks for playing
I always enjoy seeing the physical universe redefined

have another day
Dr.WtS

Hi Doc,
I made sure that I mentioned that my bullet nose example satisfied myself. I brought it up because it can be pretty straight forward to factor in the various forms of base damage and contact damage. I believe my example can affect how true the bullet flies at much lower speeds than in your opinion.

What I find fascinating is you can make consecutive comments about how surface area can matter, and then not.

If they're all spheres, there are going to be less of the bigger spheres, so there will be a lower number of points contacting. If you think that's where they'll distort, and to the same degree as a smaller sphere, then maybe there will be a LESSER surface area of damage to the bigger sphere. Do you think that's why someone mentioned that the industry may go to higher antimony for smaller shot sizes?

Also, haven't you ever noticed that it takes more pounds pushing on the lesser square inches of a smaller bore to end up with the same velocity? I agree with you, maybe tw has it figured out the best, but is it facts like yours or opinion like ours.

I can't believe that I'm doing this.

I have never seen, nor have I ever heard of the ammo industry being concerned about lead nosed bullets, traveling at several times the velocity of shot, deforming in-flight.

I did say there was less total surface area deformed on large pellets as a simple consequence of size.

"Also, haven't you ever noticed that it takes more pounds pushing on the lesser square inches of a smaller bore to end up with the same velocity? "

A nothing less than astounding statement. Does the formula F=MxA ring a bell?

And a final note to all you squashy people, a hint: Newton's Third Law of Motion.



have another day
Dr.WtS

Thanks for all your posts and comments. Please continue as needed.

Me neither wonko, I can't believe it.

When did I ever write 'industry'. If you want, I can read it to you, I was hoping you might be able. I revisited it because you revisited it, nothing more stated or implied.

As to your f=ma. Again, you're off track. So what if you can recite a generic formula. How does it calculate deformation of the pellets? I'm with cpa, I encourage you to continue.

Thank you for pages 5 through 9 of this thread. If not for the discourse contained therein, I might have forgotten that I was at DGS

WTS comparing ballistics for large lead masses (bullets) imparted with greater energy and rifled rotation with far smaller and more fragile lead pellets travelling slower is not completely valid. While lead bullet deformation is different from shot even with lead bullet casting the hardness of the lead alloy is a considered factor, this is because deformation is a factor here as well. Even artillery projectile surfaces are a considered factor in the development of indirect fire accuracy.

You constantly use the term BS, a great way to argue rhetorically, but fundamentally flawed in reason and not helpful.

Deformation does occur, it is a signicant factor in patterns as is shot stringing and it has been demonstrated by writers already cited. It is obvious to me that those who believe the opposite are not to be convinced.

My only regret in this discussion is throughout I have been travelling in North Carolina and do not have my library at home in Kansas in hand to cite in specific quotes. That said, I doubt they would convince some anyway.

The bore area of a 12g is 75% larger than that of a 28ga.
Put an ounce of shot in both & the column will be 75% longer.
To move that "Mass" with the force applied to only 57% of the area requires either a higher pressure per Sq In, longer burn time or in most cases both. Yes per square inch the longer column give more inertial resistance to moving. That doesn't contradict any of the "Laws" you have cited. I may well be a "Dumb Country Boy" & not as highly educated as you are but I am Not totally Ignorant.

I spoke at length with Tom Roster this afternoon by telephone. I was really appreciative, and little surprised, that when he answered he took the time to talk, but he did. I asked him if anybody had ever done scientific testing on lead shot loads to determine if lead shot deformation, due to setback at ignition, was greater in any area of the shot load than any other area. I told him I thought I remembered reading about some such testing many years ago, and had searched the 'net for the last several days trying to find such, but had struck out. He said that someone had indeed done that, about 30 years ago, and that someone was him. What he did was basically this: Tom, who doing a research paper at an institute of technology somewhere, painted lead shot, from the same bag, three different colors. He then loaded it into a regular shotshell load in three layers ..... one color for the bottom third of the shot column, one third for the middle, and one third at the top ... each layer a different color. He then fired the loads (more than one) into a tank of water. (He paused to remind me that water will NOT deform a lead shot pellet when fired into it). Then, he recovered the pellets and segregated them by color. He said it was VERY obvious that the pellets that were on the bottom of the load were much more deformed than the one-third layer above it, and that the top third were the least deformed.

I had remembered reading about this test long ago, but could not put a finger on who did it and when, could not find evidence of it on the 'net, so did not mention it earlier in this thread. It just so happens that the one I called was the one who actually did the testing. Tom said the tests were not ON the net, because the net had not been invented when he did the tests, and he had never put the results on there.

He went on to tell me about two other tests he had done concerning lead shot pellet shape ballistics, but they do not pertain to this particular issue.

I refused to discuss this with the arrogant, and ill mannered individual who has replied several times here, but this may be interesting to some other cogent, and truly, sane board members here. What the other individual thinks of it really doesn't matter to me.

SRH