Yards vs. Meters !
#1
Typical Buck
Thread Starter
Join Date: Feb 2003
Location: North East PA. but not home.
Posts: 743
Yards vs. Meters !
I have a few guns i shoot and load for. I go to 2 different shooting ranges. The one is a Bench Rest/100 yard range. It is level and well taken care of ? The other is just there because it is a trap shooting club,but it goes out to 200? It is sort of down hill to the 100 yd. back stops and up hill to the 200 yd. targets?
The 200 is 10 miles closer to home so i try to go there most of the time. If i shoot in at the 100 BR range my guns do what i want. Then i go to the 200 one and they are different. I just found out that the 200 is meters! Never ask any one,just took it forgranted it was yards!
How often i thought some thing had happened to my scopes or loads,going from one to the other range!
Boy,i feel so dumb!!!!
Any thing like this ever happen to you?????
The 200 is 10 miles closer to home so i try to go there most of the time. If i shoot in at the 100 BR range my guns do what i want. Then i go to the 200 one and they are different. I just found out that the 200 is meters! Never ask any one,just took it forgranted it was yards!
How often i thought some thing had happened to my scopes or loads,going from one to the other range!
Boy,i feel so dumb!!!!
Any thing like this ever happen to you?????
#3
Giant Nontypical
Join Date: Oct 2013
Posts: 9,230
#4
Depends on the load you're shooting. Off the top, I know 200 vs 225yrds in the 325grn leverevolution from my wife's rifle drops 7", so if I shot a dialed 200yrds over 200m, she'd probably fall 5" under. My 44mag with 300grn xtp's gets ~15" from 200 to 225yrds, so I'd miss by around 10" if I dialed 200 for a 218 shot. Of course, a standard bottleneck cartridge around 3000fps will only vary an inch or two, but he didn't say what he was shooting.
#6
I have a longggggg list of excuses I use also.
I'm going to add; oh, meters not yards to my list too................................ LOL
Shoot for tight groups; miss by 2" , no big deal !!!
I'm going to add; oh, meters not yards to my list too................................ LOL
Shoot for tight groups; miss by 2" , no big deal !!!
Last edited by Sheridan; 11-22-2014 at 07:35 PM.
#8
Giant Nontypical
Join Date: Oct 2013
Posts: 9,230
B.S! I assure you that if I sight in a 300 Mag for a 200 yards point of impact it won't drop an inch over the next 60 feet. Ever heard of physics? Might want to look at some of the ballistic software they have out now.
#9
What happens on paper or on a calculator doesn't matter nearly as much as what happens in the field, so I'll start here: With a 100yrd zero in my own rifles my wife dials 5 clicks on her Savage 300 from 200 to 225, I get 11 clicks with my Rem 300 (1/8MOA clicks). About 3" drop at 200, about 4-4.5" at 225.
Now, taking your advice about checking the calculators out there, I'm babysitting my son and nephew this morning (instead of being in a stand where I belong), watching cartoons, so I took the time to follow your last line and double check my own range cards and see what different available calculators would show:
180gr 300wm at 2950fps with 100yrd zero:
- Litz's "Shooter" app: -2.9" at 200, -6.3" @ 250, estimating more drop on the back end of the 50yrds than the front end, that's easily an inch at 220
- Hornady's site: -3.0 @ 200, -4.6 @ 225
- Handloads.com site: -3.35" @ 200, -4.7" at 220
- Winchester's site: -3.0 @ 200, -4.6 @ 225
- Gundata's site: -2.7" at 200, -5.8" @ 250 - same deal as Litz's app, 3" drop, ~1" in the first half
- JBM Ballistics: -3.1" at 200, -4.3" @ 220
- Berger's site: -3.0" @ 200, -4.2" @ 220
180grn pills at 2950 zeroed at 200yrds:
- Litz's "Shooter" app: zeroed at 200, -2.6" @ 250, that's about an inch at 220
- Hornady's site: zeroed @ 200, -0.9 @ 225
- Handloads.com site: zeroed @ 200, -0.9" at 220
- Winchester's site: zeroed @ 200, -1.1" @ 225
- Gundata's site: zeroed at 200, -0.92" @ 220
- JBM Ballistics: zero at 200, -0.9" @ 220
- Berger's site: zeroed @ 200, -0.89" @ 220
Or you can do it by hand rather quickly, all a guy has to do is estimate time of flight, then calculate the gravitational drop based on that ToF.
Simple math on it - or rather simple PHYSICS on it: 3000fps, 200yrds = 600ft, neglecting any velocity loss, 600ft/3000ft/sec = 0.2 sec ToF. Drop due to gravity is -32.17 feet per second per second, and the formula to calculate non-propelled gravitational drop is = 1/2 * G * ToF^2 (where G is -32.17ft/s/s and ToF = time of fall) = .5 * -32.17 ft/sec/sec * 0.04 sec*sec * 12"/ft = -7.7" total drop at 200yrds. 220yrds = 660ft, 660/3000 = 0.22 sec ToF, .5*-32.17*0.0484 * 12 = -9.3" total drop at 220yrds. So between 200 to 220yrds, that's about an inch and a half of drop. A guy can make a small correction that for 100 or 200yrd zeroes, you'll peak somewhere between 75-125yrds, so call it 100yrds, so the bullet only starts dropping there. So if you cut off the "rise" part of the trajectory, then you get the drop from 100 to 200 and 100 to 220yrds = 0.1sec vs. 0.12sec, yielding -1.9" vs. -2.8" for 200 and 220yrds respectively. Good for about an inch of drop over those 20yrds - obviously, real world bullets slow down in flight, so those ToF's are too short, and the drop would be slightly more. This math doesn't care about zero'd range, only about Time of Fall.
Seems to be pretty much exactly one inch for a 300wm from 200-220yrds, whether you have a 100yrd zero or a 200yrd zero...
Last edited by Nomercy448; 11-22-2014 at 07:10 AM. Reason: Re-ran simulation for 200yrd zero...
#10
Giant Nontypical
Join Date: Jan 2011
Location: Allegan, MI
Posts: 8,019
I think we just got schooled on bullet drop regardless of caliber! 1" in that short distance sounds like a lot from a high powered center-fire rifle, but it really isn't when you start looking at the charts mentioned.