Attention wildcat bullet shooters!

[dakor]

I must be missing something here but if you shoot one bullet makers bullet and another bullet makers bullet under the same conditions and at the same FPS and one drops more than the other. I would say the one that dropped less has A higher bc and I dont know how anyone can agrue that? I also dont understand how you can argue when someone determines a bullets bc by how much it drops with a 100 yard zero at 500 yards. How is that any different then shooting it over a Chrony at a certain range? What people also have to understand is the Wildcat bullets that have really high bc's are heavy for the cal they are in. If a 7mm 180 Berger can have a bc almost of .700 you dont think a Wildcat bullet that is 20 grains heavier could have a bc of or close to 1.0? As for the comment about BR shooters they are sheep and will follow whatever the norm is at that time. 10 years ago you had to have a 300 Win Mag or 30-338 to win matches at 1000 yards. Now you have to have a 6.5-284 and tomorrow you will need a 6mm Dasher. /ubbthreads/images/graemlins/grin.gif The only reason Sierra's have won so many matches is because everyone was told you have to shoot them to win. If I put 25 chevy's on a track and only left room for 5 fords who is going to win more races? I think there are lots of bullets out there that are better then Sierra. As for how good are Wildcat bullets? I have not recieved mine yet but after looking at Kirby's 1800 yard group and the groups GG was getting with Sierra's I think at this point I would take the Wildcat bullets over the Sierra.

 

[4ked Horn]

[ QUOTE ]
4kedhorn,
I completly agree with everything you said, in fact I have already stated almost everything you have said! I know that his BC figures are predicted by the mfgs of his dies, and that they are approximate. Please review my previous posts for verification. I have exchanged emails several times with Richard. if you are interested, the pitchfork is still in the barn. It will stay there. No torch either, except for the british, then I have a surefire P9. Sorry, a weak attempt at flashlight humor.

[/ QUOTE ]

I'm with ya'. I suppose the tone of what you wrote sounded less like an interest in discovering the truth of the BC question and more like "I'm calling bull and I'm going to prove it." I read this whole thing within minutes of getting off the phone with him so I'll admit I was feeling defensive of him. I'm glad we agree and once again find ourselves on the same side of the issue after all. He has expressed an apprehension at offering ANY BCs because of the missunderstanding of where he is coming from with them. I am not saying you are at fault. I'm just telling you (and others reading this).

I think you and the others with the ability to concoct reasonable real world BCs have a great opportunity to work with Richard to discover what he can actually produce. Heck I bet he would negotiate a fair price for bullets that were being used to benefit him with BC research he could stand FIRMLY behind.

THAT is good for Richard and us as well.

As for those emailing you because they are afraid they don't have enough experience. Make sure you all ask your questions here in the forum at some point so we all benefit. If all of us skittered around in emails this forum would fall appart and what good would that be? Don't be afraid. We are all friends here. Friends just dissagree from time to time. Thats how we learn things sometimes.

Abinok I want you to notice in another post that I am working on a bullet from Wildcat bullets for my .308. The choice for a 175 grainer is a direct result of you speaking up on my bullet choice poll. I'm glad you spoke up boldly when you did.

 

[Jon A]

Don't worry about it, Kirby. No offense taken at all. /ubbthreads/images/graemlins/wink.gif

 

[goodgrouper]

[ QUOTE ]
I also dont understand how you can argue when someone determines a bullets bc by how much it drops with a 100 yard zero at 500 yards. How is that any different then shooting it over a Chrony at a certain range?

[/ QUOTE ]


This way can work, but it is not the most exact. Very rarely can you have conditions perfect enough to not interfere with your data. Even in indoor 300 meter ranges where conditions are perfect and controlled, they still use chrony's to test bc. It is just more exact. The problem is that not everyone can afford two chrono's or one Model 43!


[ QUOTE ]
I have not recieved mine yet but after looking at Kirby's 1800 yard group and the groups GG was getting with Sierra's I think at this point I would take the Wildcat bullets over the Sierra.

[/ QUOTE ]


It might seem like I'm harping on you Dakor, but believe me I am not. I just think that you are making a statement here which is not totally founded on fairness. You are comparing two groups shot on different days, by different guns, by different people (four people in fact shot our group you saw, and only Kirby shot his group), and our group was shot 200 yards farther, which at that range provides the bullet another 11 minutes of drop in that last 200 yards! Also, his group was 3 shots, ours was a 40 shot group! There is an ocean of difference there.

I do agree with you that the Wildcat bullets have huge potential. I am waiting for mine to show up anxiously. But I think when comparing bullets, it needs to be done by keeping as many of the variables the same as possible. There are certain facts that can be discovered about bullets without ever putting velocity to them though. One can measure weight, ogive length, boat tail diameter, meplat uniformity, and others things between two bullets to get a pretty good idea of consistency. That being said, I do believe that the Matchkings leave some room for improvement in some areas, and I am waiting to test this with the Wildcatters.
Good shooting!

 

[Fiftydriver]

Dakor,

We think alike, "simple", that generally works out the best, to keep things as simple as possible.

On the Wildcat 7mm bullet front, the +1.000 B.C. projection is actually for a 210 gr ULD RBBT. These are only projections but adding 30 grains to the 180 gr Berger would seem logical to get back a near 1.000 b.c.

I would recommend shooting and testing both the Sierra and the Wildcat. Rifles are particular things. Some will like the Wildcats, some the Sierra. I will say, a quality built rifle will shoot both bullets very well, extremely well in fact. I just found the Wildcats to hold tighter groups then the sierras and drop less as well so I use them

To shoot only one bullet in a rifle without testing others is really foolish. Test for yourself and prove it to yourself what your rifle prefers.

Rifles are very honest about what they prefer in a bullet. We just have to listen to them!!

Good Shooting!!

Kirby Allen(50)

 

[Fiftydriver]

Goodgrouper,

I totally agree with your comments to Dakor. Obviously both rifles and loads shoot very well. My rifle also shoots very well with the 300 gr Sierra as well. But to compare such limited groups is not a fair comparision.

I only shot one group. I will say that at a mile, the shots on the dialing in rock were gernerally in the 3/4 moa range for three shots, but again, this was limited shooting.

How much can a guy get in on a lunch break /ubbthreads/images/graemlins/grin.gif!!!

Again, I will say that anyone that does not test a sampling of the top bullets out there in their extreme range rifle will more then likely not be using the best bullet in their rifle.

I will also say, there is not a quality rifle out there that one could use either the 300 gr Sierra or the 300 gr or 350 gr WIldcat bullets in and get great groups. They are just both great bullets. Again, in my rifle the Wildcats just get the tighter groups. I could build another rifle to the same specs and have the Sierras have a slight edge. I would still use the Wildcats fo their other benefits though as far as terminal performance.

I agree with your comments 100% though about deciding from a limited about of provided test results. There will be more coming.

No matter what bullet I use, I certainly have the ability to really screw up a tight group at long range!!! I would say both the Wildcat and Sierra bullets offer consistancy potential higher then my ability to shoot them consistantly.

Good Shooting!!!

This conversation seems to be settling down into a decent quality debate now. Good to see. The more bullet options the better in my mind.

Good Shooting!!

Kirby Allen(50)

 

[abinok]

I too am happy to see this thread settle down a little, and im looking forward to getting that little box in the mail. I thumbed through a couple books on the shelf that I thought had discussions on various ways of formulating BCs, but couldn't find it. Ill look some more after lunch.
In the mean time, enjoy this brief explination....

The problem with calculating BC from raw drop data (as in shooting at a target at 300yds with a zero for 100, and measuring the drop) is many fold. Lets setup a little example....
Say we take our rifle out to shoot at 300yds. We have a 100yd zero on a rifle that spits a 168grSMK at 2800fps. We use our LRF to range the target. It says 300. Out drop chart says we should see 13.29" of drop. The problem begins with the fact that most LRFs are accurate to +-1yd, which means the target could be as far as 301.9 yds, or as close as 298.1yds.Your drop data would generate a BC value that could vary substantually.
298.1yds .490
300.0yds .462
301.9yds .434
This creates an error of .056 just from the limited precision of todays LRFs.
This example eliminates any problems due to variances in muzzle velocity, or changes in muzzle velocity due to temp changes. Add in a 10 or 20fps ES of all the rounds fired, and you get even more variation.
2800 13.29
2790 13.46 or .18"
2810 13.11 or .17"
20fps es would add .35 to your error and take your BC "measurment" up to .55
You could consider how all of the various 6DOF variables would come into play... say, how much vertical will a full value 10mph wind give you at 300 yds?
Maybe i'll do these later...
All of these variables are compounded as range increases, especially if the resolution of your measuring device is not comprable to a steel tape measure ie. inches.
Using this method at longer ranges also has the complication of the need to fire a large number of rounds to find the exact center of the group from which to measure. If a mismeasurment of around .4 at 300yds can cause a miscalculation of a .462bc to be .55, imagine what missing the center of a 1760yd group would be if a flyer (or flyers) opened the group enough to move your group center by only a couple of inches! Remember that this is both a question of from where do I measure, and where are the bullets impacting in relation to my POA due to interfeering weather?
If you make the jump from this raw data to clicking up to a range, you then add to the equation any inconsistancies of the movement of your sighting system. Further, there is the extreme need for precision in calculating the comeups at long range. For example MOA is not 17.6", but much closer to 18.430". I still rounded to get this number. This would add up to a measuring error or .1" for every click you dial at this range.
Hopefully this made some sense to somebody out there. My point to all of this is that calculating a relatively accurate BC from drop data is possible, but much more difficult than it might appear at first glance.
Using the chronograph eliminates all of this error and creates much more accurate and reliable data, and this data is what im after. /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif

Fiftydriver, I absolutely have no ill will towards Richard, and if the results come back as the bc is lower than estimated, but they shoot well, I will likley use them for my LR single shot load in certian instances. If they shoot well and have the predicted BCs, Richard will have no louder promoter than me! Like I said, as soon as that little box arrives, all questions will be answered.

 

[dakor]

GG I understand that but if you also look at Kirbys targets at 500 yards With a couple different cals he has shown on here it is hard to argue that Wildcat bullets are not accurate. I know you had a 40 shot group and I am not saying your rifle is not a shooter because believe me I think it is really impressive and anytime you want someone else to test it for you just let me know. /ubbthreads/images/graemlins/grin.gif But what some on here do not understand is the bullets Kirby has been shooting are big game bullets not target bullets. They are not desinged to shoot paper they are designed to take a impact at 50 yards and still open up way the hell out there. To me that is very impressive. I know Sierra bullets can shoot I shoot a lot of them but they dont make a bullet in the cals I shoot that can take a beating at 50 yards and still open at 1000 yards. About the only thing that comes close is the 300 grain Matchking for a 338. As for my Wildcat bullets I have some 7mm 175 grain ULD point flatbase which will have a bc around the .700 mark. Even if the bc only turns out to be .600 I would still be happy if they shoot well. I also think a bullets published bc is just a guide kinda like a reloading manual. Every rifle is different and bc can be change with so many Variables. I think when one wants to find a bullets bc you have to do it rifle to rifle.

 

[goodgrouper]

10-4 on that buddy.

[ QUOTE ]
and anytime you want someone else to test it for you just let me know.

[/ QUOTE ]


You are always welcome at my shooting bench. If you are ever in the Provo area, give me a holler!

 

[Matt27]

goodgrouper

yeah that was base to ogive.

If i remember right Richard should be getting his dies back by the end of the month if not sooner.

As i have never checked my bullets before and if you find alot of variance i am sure Richard would like to know. He is very particular in what he produces.

 

[dakor]

Well thanks GG and if you are ever up in ND give me a call. I really hope you post the results of your Wildcat bullets when you get them.

 

[STL_Shooter]

Someone mentioned that I quote JLK BCs and then question Wildcat BCs...

I don't quote anything from Jimmy Knox - my numbers have been verified by chrono to 600 yards at around 800 ft ASL and via drops to 1000 in western MO and to 2000 somewhere in central South Dakota. Then Brent and others verified with similar numbers (Brent has an Oehler, I don't remember what everyone else over the last few years has used) in their respective locations...

 

[ricka0]

Hopefully the applied mathematician in me won't BIG TIME bore everyone to tears. I'm sure we are all aware that BC is dynamic, not a single number, ie it depends on Velocity.

When folks talk about using <font color="red"> a <font color="black">chronograph to get the BC, I hope they mean using <font color="red"> a PAIR <font color="black">of chronographs unless they are doing the correct statistics (which means you would need a lot of measurements too unless you have an exceptionally low StdDev in velocity). I believe Doppler radar is the preferred method to accurately get BC.

[ QUOTE ]

<font color="red">
Everything and anything affects this number. These are just a few bc tweekers:



[/ QUOTE ] <font color="black">

Actually, the only things that effect BC are physical, ie topology (shape, defects) . axial symmetry, density and velocity. the new list
<ul type="square">[*]barrel condition
[*]bullet bearing surface
[*]bullet meplats
[*]bullet dings/scratches
[*]Weight of individual bullet
[/list]

The following factors only change effective BC, not actual standardized BC. IE, these are environmental factors that effect bullet flight but have impact on corrected BC – ie if you corrected for these factors, then tested the bullets at Std Temp, pressure, Humidity, (I believe Altitude can be rolled into pressure), wind vector – you would get the same BC value. If you moved to another pressure/temp/humidity location you would still get the same BC.

Twist can also be corrected for sans sub stabilization. If you know the true BC, ballistics can accurately calculate the Velocity, [de]Acceleration, position at any position or point in time - pre subsonic. Precipitation could be corrected for but it would probably be too difficult to accurately quantify rain/ice conditions.

Properties that effect perceived BC but not actual Standardized BC
<ul type="square">[*]Humidity
[*]barometric pressure
[*]air density/altitude
[*]temperature
[*]wind direction
[*]wind speed
[/list]

[ QUOTE ]

<font color="red">
There can never be two bullets in the same box with exactly the same bc.


[/ QUOTE ] <font color="black">

Perhaps if you want to get into quantum physics but given a large enough batch you could find identical BC bullets <font color="red"> within the bounds of your measuring tolerance <font color="black">

That is where Standard Deviation comes in. If you know the Std Dev of a batch, you know expected variation. If you further add extreme spread, you know everything.

I'm not flaming or picking on you goodGrouper – I respect the awesome work/shooting/experience/info you bring to this forum. I hope to some day get 90% of the results you are getting today.

 

[ricka0]

Kirby don't take offence, you know I'm your #1 Fan.
Drop charts are fine in you're always hunting at the same elevation/temp - But I'm using my 300 RUM (until you ship me my Kirby/Lilja 300 RUM /ubbthreads/images/graemlins/smile.gif ) for yotes outside Bakersfield CA - hot &amp; low altitude. Then I'll be using it for deer along the Missouri Breaks next fall ( 3,500 ft ) then moving to my cabin near showdown ski resort ( 7,400 ', cold ) - yotes/rabbits in goodGrouper s stomping grounds (santaquin UT ) - then on to the Nevada dessert.

I can't do a drop chart at each location, but once I <font color="red"> Calibrate </font> a ballistics model, I can move to any of these locations and very accurately compute drop.

If you want to use drop to approximate BC you can get more accurate results if your scope is exactly parallel with the bore.
A couple problems with using the drop approach is you need to know the Std Dev of velocity spread and BC to compute a BC #. IE, if bullet 1 has a BC of .700 and #2 has a BC of .710, then you get an inflated BC approximation. So you really need to know both Vel and BC to compute BC. This can actually be done by estimating the BC and using some statistics.

Getting the Velocity at two positions from one bullet gives you ZERO variation in BC and Velocity.
Wind, pressure, temp variation are also minimized.
I suppose you could do some non-trivial statistics to correct for these variations and use only the drop approach, but depending on the consistency of your groups this could involve many test shots. I need to think about how you would correct for two significant variables (vel &amp; BC) – You see the problem, bullet 2 has higher Vel but lower BC, bullet 3 has lower Vel but higher BC.

As my other hero goodGrouper eloquently pointed out BC changes from bullet to bullet, minute to minute. ( I think he left out barrel temp )