BigGameHunt.net Hunting Forums

[bzzboyz]

I don't know fps from FBI. I just know what my rifle does and I go to the range a lot. I zeroed it out at 200 and thats how much adjustment I have to make on it at the distances I stated with a balistic tip. If I switch to a nosler tip, then it's pretty close to what you stated. But I do stand corrected a little. It's probably more like 3" at 300 and 6" at 400 now that I think about it, but I haven't taken a shot over 300 in the field in many a year.

[Hiker]

Here's Mig-Hunter's 2006 Montana Antelope....

[Hiker]

Nice buck! :thumbsup1:

[ndemiter]

the 25-06 is a good gun for critters like pronghorn, but the small bullet weight doesn't help for retaining energy or velocity at long range. as long as you hit what you're aiming for, it would do the job at 400 yards. however. it's just not a easy shot with light bullets. wind velocity changes dramatically across prairie country. it might be a light breeze where you're standing, but a heavy gust may be funneling from a coulee 150 yards between you and the goat. personally, i'd keep it inside of 250. another advantage of that, is that it's just an easyier shot.

you could switch it off for the good old .30 caliburs too. where maximum point blank range is 200 yards. (meaning, you're about 1" high at 100, center on for 200, and 3.5' low at 300... which means unfortunately, 11.75" low at 400 {this is for IMR 4895 charge of 47.5 gr and a 150 gr ballistic tip bullet... plus cci benchrest primers})

[SoCoKHntr]

Don Fischer wrote: bzzboyz,

I'm couroius about the trajectory of your load. You said 1" high @ 100, dead on @ 200, 1" low @ 300 and 3" low @ 400. Where do you get those figures?

According to the Nosler manual, their max velocity for the 115gr BT in a 25-06 is 3116fps. Figuring 3100 fps with Noslers book and a zero of 200yds I get 1.3" high @ 100 6.2" low @ 300 and 17.9" low @ 400yds?

That's what I was thinking when I read that. I've heard good things about the 25-06 and I am no expert but those numbers would make it the flattest shooting hunting round I've ever heard of. That would give you a dead on hold out past four hundred yards on an elk heck an antelope. bzzboyz I agree with Don you are mistaken.

[ndemiter]

i've found the factory tables to be less than helpful in real world application. i should state that i've never shot paper at 300+ yards. but i've shot a few woodchucks. accuracy of factory data seems to be close (+ or - an inch or two, maybe at the long ranges.) my load tables tell me that a 150 gr hornady interlok, 48.7 grains of imr 4895 out of a 30-06 gives me ( an estimated) 2975 fps. at the muzzle. i use the muzzle velocity to calculate the rest for my self. (although actual is probably closer to 2850 fps)

you can determine your energy in foot/pounds by (1/2)Mass*velocity^2 (keeping in mind that one grain is approximately equal to .0645 of a gram, and you need to divide your answer by the accelleration due to gravity to cancel the unit of newtons.) (all my work was done in metric, including velocity) then i apply a deceleration model to the projectile, including various hydraulic influences such as the fluid viscosity of air (the bulk modulus of air and young's modulus of the bullet material ((copper coated lead!))). (in reality, every figure (for different loads) is going to have a standard deviation from the mean by about one order of magnitude, or a factor of 10. so the value may be

this is due to the fact that you are assuming things like air pressure, the distance of the barrell from the ground, even the build of the shooter. {flesh behaves as a fluid under pressure... and fluids have a precarious way when it comes to pressure... e.g. making this a very complicated problem}.

but, since i like to hunt, and college is boring, i spent the majority of my time in two upper level physics classes classifying these forces in order to make a complicated ballistics model that can be used in conjunction with charts and tables of air pressure, shooter weight(accounting for the vector math forces) and temperature to account for this. my original hope was to be able to apply this to all projectiles, but in my testing of the model, it was really not practical, it in fact took me weeks to do a single example, so i calculated some similar values for instance the 30-06, and the .308, and even my .41 rem mag for the fun of it. even though the applied forces were all wrong.

the data from the model i produced is similar to other data readilly available online. however notable differences occur at close ranges from 0-75 yards, and long distance between 300-500 yards. factory tables are good ESTIMATES for 100-250 yard shots. each distance being the cutoff point of accuracy.

keep in mind, the figures you get from industry websites, and handbooks are designed with specific intentions like to show the fastest muzzle velocity coupled with the highest energy values. their data is entry-level statistical optimization (which is the corect mathmeatical term for their information) so sorry for the rant, but their numbers aren't necessarily correct, they tell you what you want to hear, not what you need to know.