Ballistic Calculator

[Steve M. Galbraith]

Thanks for the nice work and information Joe! Just out of curiosity, does anyone know the approximate distance of the shot that missed at the house of General Walker? I think that I have read that it is a relatively close-range shot also. But just wondering how it compares distance-wise to the shots in Dealey Plaza.

In his book on the assassinations of Lincoln and JFK, John Lattimer theorized that it was less than 100 feet. That's if Oswald got inside the fence of Walker's backyard.

Source: "Kennedy and Lincoln: Medical and Ballistics Comparisons of Their Assassination", pg. 134.

[Richard Smith]

According to Marina he spent at least two months preparing for the Walker shooting and you suggest he didn't practiced with the the rifle!

Any doubt that you're genuine Nutter material has now been eliminated.

 

I thought it was contrarians who didn't believe Marina?  Going on and on asking for "corroborating" evidence of what see observed.  LOL.  Try to be consistent.  Oswald missed Walker only because his bullet deflected off the window frame.  You can see the damage in photos.

[Richard Smith]

Based on your premise that Marina, being Oswald's own wife, would be the Nutter's preferred witness.

Perfectly consistent.

 

Good.  So you finally agree that Marina saw a "rifle" in the blanket and took the BY photos!  Progress.

[Richard Smith]

No, I simply pointed out that a nutjob who believe in the Walker fantasy can't put together a coherent argument.

BTW, did you work out why he only brought one round?

LOL

So you cast doubt on Marina when she says that she saw a "rifle" but then suggest in another context that it is unreasonable for someone to doubt her testimony about Oswald practicing with a rifle (something you have argued yourself).  But then suggest that others here believe in a fantasy.  And finish with the standard LOL as though you have proven something (which should be SOL in your case).   The rabbit hole beckons. 

[Brian Roselle]

Joe,

Your analysis approach looks interesting and inputs look pretty good to me. Nice job pulling it together.

I've only used a trajectory calculators briefly before and don't have much experience with them so I wondered if you are familiar enough with this trajectory calculator to have any sense on how sensitive gravitational drop distance might be to muzzle elevation?

I am actually asking this because of the first shot that missed. That is the shot I have spent some time on and I am in the camp of a pretty early missed shot that would necessitate a fairly steep muzzle elevation deviation from horizontal toward vertical, and if the bullet drop distance, relative to say a laser line of sight, is largely related to flight time (while gravity is acting), it may simply be that be the muzzle elevation doesn't have much effect.

Maybe running the calculator by changing only the muzzle elevation from 0 to -30 degrees or something would give the same drop in a given time versus the respective bore site. I suspect the calculators don't make a distinction between X (horizontal) and Y (vertical/gravity) direction of travel relative to the effective ballistic coefficient used.

Just sort of curious on these trajectory calculators. I have never done any hunting is why I never really used them, but I have done some target shooting in the past and I think I might have gotten a marksman merit badge in cub scouts, but I was told I wore pants that looked like Maggie’s drawers.

[Charles Collins]

The information provided by Joe regarding the ballistics appears to me to be to be enlightening with respect to the scope limitations when attempting to zero-in at 100-yards. There are multiple aspects to consider regarding zeroing-in the side-mounted scope. But to focus on one of them, it appears to me that if the scope was originally mounted by using the typical bore-sight method, then, elevation-wise, it should have been closely matched to the stationary iron sight’s 200-meter zero-in distance. This is due to the ballistics calculator showing only about a -0.1” impact (in elevation) from the centerline of the barrel at that distance.

Looking again at the ballistics calculator data for this rifle and ammunition, we can see that at 100-yards the impact of the bullet is 5.76” above the centerline of the barrel (bore sight line). The scope is an inexpensive relatively small (compared with a typical high-powered hunting rifle scope) scope. It is more typical of one we might put on a .22 caliber rifle and use to learn to shoot with (similar to what I had as a teenager). When reading Robert Frazier’s description and diagrams as testified to the Warren Commission, it appears to me that the adjustment necessary (5.76”) to zero-in the scope at 100-yards is close to (if not exceeding) the range of adjustment available in the mechanism of that scope. And I suggest that the description of a “defective” scope that has become common in this case, is not accurate. I believe that a more accurate description would be that the limited range of adjustment of that scope doesn’t allow it (as mounted on that rifle) to be easily zeroed-in at 100-yards.

Taking this further (and making some assumptions) it appears to me that LHO did make some detailed plans before he attempted to shoot General Walker. Also, it seems to me that if the scope on the rifle was defective and/or useless, that he would have taken it off. So, when we look at the ballistics calculator again for the distance of the shot at Walker (only ~100-feet, or 33-yards) the impact of the bullet is only about 2.5” above the centerline of the barrel (bore sight). If I am thinking about this correctly, the available range of adjustment of the scope should allow this much smaller amount (compared to the 5.76” required at 100-yards). But I could be wrong, so please feel free to correct me. So, it seems to me that it is probable that in all the careful planning that was apparently made for the Walker shooting, the distance of the shot should have been noted and estimated. And that the scope could have been zeroed-in at that distance when practice shooting the rifle. And if that is what happened, then it seems to me that (assuming normal careful handling of the rifle) when the rifle was used in Dealey Plaza that the scope was probably still at or close to that setting due to an apparent lack of time to zero-in the rifle again before the shots were taken.

[Bill Chapman]

The information provided by Joe regarding the ballistics appears to me to be to be enlightening with respect to the scope limitations when attempting to zero-in at 100-yards. There are multiple aspects to consider regarding zeroing-in the side-mounted scope. But to focus on one of them, it appears to me that if the scope was originally mounted by using the typical bore-sight method, then, elevation-wise, it should have been closely matched to the stationary iron sight’s 200-meter zero-in distance. This is due to the ballistics calculator showing only about a -0.1” impact (in elevation) from the centerline of the barrel at that distance.

Looking again at the ballistics calculator data for this rifle and ammunition, we can see that at 100-yards the impact of the bullet is 5.76” above the centerline of the barrel (bore sight line). The scope is an inexpensive relatively small (compared with a typical high-powered hunting rifle scope) scope. It is more typical of one we might put on a .22 caliber rifle and use to learn to shoot with (similar to what I had as a teenager). When reading Robert Frazier’s description and diagrams as testified to the Warren Commission, it appears to me that the adjustment necessary (5.76”) to zero-in the scope at 100-yards is close to (if not exceeding) the range of adjustment available in the mechanism of that scope. And I suggest that the description of a “defective” scope that has become common in this case, is not accurate. I believe that a more accurate description would be that the limited range of adjustment of that scope doesn’t allow it (as mounted on that rifle) to be easily zeroed-in at 100-yards.

Taking this further (and making some assumptions) it appears to me that LHO did make some detailed plans before he attempted to shoot General Walker. Also, it seems to me that if the scope on the rifle was defective and/or useless, that he would have taken it off. So, when we look at the ballistics calculator again for the distance of the shot at Walker (only ~100-feet, or 33-yards) the impact of the bullet is only about 2.5” above the centerline of the barrel (bore sight). If I am thinking about this correctly, the available range of adjustment of the scope should allow this much smaller amount (compared to the 5.76” required at 100-yards). But I could be wrong, so please feel free to correct me. So, it seems to me that it is probable that in all the careful planning that was apparently made for the Walker shooting, the distance of the shot should have been noted and estimated. And that the scope could have been zeroed-in at that distance when practice shooting the rifle. And if that is what happened, then it seems to me that (assuming normal careful handling of the rifle) when the rifle was used in Dealey Plaza that the scope was probably still at or close to that setting due to an apparent lack of time to zero-in the rifle again before the shots were taken.

My understanding of factory-zeroed-in-at-230m means that the sights do not have to be adjusted between 0-230m