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Drew_CarreyAB
11-21-2005, 09:03 PM
O.K, My dilema(sp) starts with this.....Your scope is dialed in for bang-on at 100 yards, the drop chart says that if the target is 300yds away the bullet will drop 19.6" (.303 Federal 180gr). Now at 1/4" per click do I turn up the elevation 78 clicks or is it like when shooting groups(they say that if you shoot 1" @ 100yds, the group will open up to 3" @ 300yds). So would it be more clicks or the original 78????? Hope this stumps someone else too LOL

HPBTMTCH
11-21-2005, 10:55 PM
Whoa there drew, why dial the scope for 100 yards? 200 yards would be a lot more practical. Now the other problem. You need 19.5 inches, or 19.5 minutes at 100. At 300, each click is worth 3/4 of an inch. So you would need 6 and a half minutes up. 78 clicks would be 14.62 minutes at 300, and the bullet would strike 10 inches high. Depending on optics, you group a 300 will probably be more than 3 times as large. Wind has some effect out there also. Hope this helps.

Drew_CarreyAB
11-21-2005, 11:08 PM
so you would triple/quadruple(or whatever) the distance to the target?? I kinda thought that was what it was, but I was unsure.

bigbrother
11-22-2005, 08:16 AM
The first thing you have to consider when figuring number of "clicks" to compensate for drop is MOA vs. Inches in drop. Your scope is listed as 1/4" clicks at 100yds but in reality each click is 1/4 MOA (4 cliks = 1 MOA) 1 MOA at 300 yards is 3".( 19.5" divided by 3) 6.5 minutes is the correct elevation adjustment (6.5 x 4 clicks per minute = 26 clicks to put you dead on at 300 from a 100yd zero) Hope that isn't too confusing. (it would work the same for as far away as you want to shoot. If you know you'll be 50" low at 500 for instance, divide 50 by 5 and you know you need 10 MOA or 40 clicks) I make my drop chart in MOA not inches that way I can just dial to the proper moa marker on my scope. (my scope has 15 MOA of adjustment in one turn marked in 1/4 moa increments with the whole numbers marked as 1,2,3,etc) Therefore if I need 30 MOA to reach a deer at 1100 yards, I know I need 2 complete turns from zero. This also allows me to not have to "return to zero" from every shot. I don't have to remember that I came up 36 clicks for the last shot now I need to be up 54 so subtract 36 from 54...or wait was I up 40 clicks...where is zero anyway??? (Trust me, that sucks I know from experience)

As far as distance for zero, that's pretty much personal preference. I know people that use tapered bases and there "zero" is 300 yards. They do that so they can use all of their scope vertical elevation to shoot targets to 2000 yards. My personal "zero" is 100. I can reach 1200 yards with my scope and gun combination from that without the tapered base. That's pretty much all the further I'll shoot a deer with that gun because my energy peters out.

The other thing is that just because your gun shoots 1" at 100 doesn't mean it's going to shoot 3" at 300. It could be tighter or larger....you need to shoot to find out. We've been taught that that theory makes perfect sence but for example: I have had guns that shot 1/4" at 100 but shot 4.5" at 300. My longrange gun now shoots under 1/2" at 100 but still shoots 3/4" at 300. Shoot your gun, it's cheaper in the long run to shoot a lot before season! Good luck and Happy Hunting this season.:D

ol_spark
11-25-2005, 01:35 PM
And....don't forget the mechanical side of things. Just because the drop chart says 76 clicks and your scope says 1/4" per click at 100yds don't make it so. You need to verify by shooting that number of clicks to find out if it's OK for your setup and scope. 76 clicks according to the chart and 76 clicks in the scope may not be the same distance...It may be 77 or even 78 ....Computer charts are OK but you need to understand that they are calculated using exact numbers. If any of those numbers don't correspond to the real world amplication, your chart may not be the same as what your scope dial says it is. .....Now that is confusing........... Point is... just verify everything by actual shooting and dialing your scope prior to shooting at game animals.

California Hunter
01-16-2006, 08:35 PM
Hey Drew, try this - sight your rifle in 4" high at 100 yards. This should make it about 6" high a 200 yards, dead on at 300 yards and 12 to 14 inches low at four hundred yards. Hold low in hair short in and high on hair at long range. These are very rough guesses for you rifle - but the complete ballistics for a 300 yard zero can be found in the back of the hornady reloading manual.