Post by: Kc_Kracker on November 02, 2012, 12:11:59 PM
"400 yards -16.4"
does that mean at 400 yards it will drop 16.4 inches? trying to get a grip on what all this is. my scope has 200, 300, 400 yards marks below the cross hairs but not sure how accurate they are im sure they do not fit all ammo perfect.
here is my ballistics for my gun and ammo, but dont know what it means :dunno:
Post by: bobcat on November 02, 2012, 12:16:31 PM
Post by: jaymark6655 on November 02, 2012, 12:17:32 PM
TMI- actually it drops more than that because your barrel is actually pointed up, if held level it would not impact the bullseye at 250 yards
Post by: Bob33 on November 02, 2012, 12:26:14 PM
They are probably quite accurate for certain ammunitions, but not necessarily for yours. Drop is determined primarily by velocity and how aerodynamic the bullet is. Everything else being equal, a faster bullet will have less drop than a slower bullet, and a more aerodynamic bullet will drop less than one that is less aerodynamic.
I would not rely on those scope marks without testing them first with your ammunition, particularly at distances over 300 yards. :tup:
Post by: bobcat on November 02, 2012, 12:39:33 PM
Post by: headshot5 on November 02, 2012, 01:02:38 PM
Post by: JackOfAllTrades on November 02, 2012, 01:29:27 PM
"my scope has 200, 300, 400 yards marks below the cross hairs but not sure how accurate "
I would not rely on those scope marks without testing them first with your ammunition, particularly at distances over 300 yards. :tup:
:yeah:
-Steve
Post by: JohnVH on November 02, 2012, 01:32:20 PM
If you do want to use the marks in your scope, you'll want it sighted dead on at 100 yards. Then be sure to shoot at all those distances, and write down how high or low your bullet actually hits.
that differs, the scopes I have with marks in them say to zero a magnum rifle at 200, and a standard at 100.. Still never had them work right for the loads I use though.
OP, notice those two charts show a different zero point.
Post by: bobcat on November 02, 2012, 01:39:01 PM
I was thinking of my 30-06 which at one time I had a Burris Fullfield II on it, and zeroed it at 100 yards in order to make use of the marks for longer distances.
Post by: jaymark6655 on November 02, 2012, 01:51:32 PM
I have a new love for NightForce and their adjustable "zero stop" Basically you can set that stop, adjust your scope for a long shot and then quickly turn the scope back down until hits that stop for close shots and your back at that original zero that you set.
For a cheap version without zero stop I use Leapers. I can set the zero, loosen the turrent and reset the turrent to the zero mark without changing the zero. Then it makes 1/4 moa clicks or I can quickly make adjustments by using the printed 1 moa markings and I print my range card to have zero at 100 and then it tells me what moa I need for each 50 yard increment instead of bullet drop. It also has mil-dot for hold over, but its a little harder to use because its an adjustable power scope and that changes depending on what power its on.
Post by: Antlershed on November 02, 2012, 06:40:35 PM
All this uncertainity. :rolleyes: Get a scope that you can set the zero and then adjust the turrents for each shot and carry a ballistic card for the round you are using. Zero scope for 100 yards anything to 200 yards you probably can just hold a bit high. Past 200 yards you will probably have time to look at card and adjust the scope before the shot.:yeah:
When I first got my .300RUM, I knew my velocity (shot thru a chrono), knew my ballistic coefficient, and of course knew my zero yardage. I plugged this in to a program and it spit out some numbers. Some of them were right, and the rest were "close". Ballistic programs are a good starting point, but there is no substitute for shooting the yardages in 50 yard increments out to how far you are willing to shoot. Do this, and then make a card to either tape to the stock of your rifle or to just carry around. You will be much better off. :twocents:
Post by: coachcw on November 03, 2012, 07:08:53 PM
Post by: Kc_Kracker on November 04, 2012, 09:48:59 AM
What brand scope.
I have a new Vortex 4-12x40mm, and so far its awesome, both ends can be drenched in rain and without wiping it off i can look in it and all is crystal clear :o where can i go and finds a place to test 200, 300, 400 yards? id really like to know where these core lokt's are plinking
Post by: Bob33 on November 04, 2012, 09:56:02 AM
http://www.cascadeshootingfacilities.org/ (http://www.cascadeshootingfacilities.org/)What brand scope.
I have a new Vortex 4-12x40mm, and so far its awesome, both ends can be drenched in rain and without wiping it off i can look in it and all is crystal clear :o where can i go and finds a place to test 200, 300, 400 yards? id really like to know where these core lokt's are plinking
Post by: Kc_Kracker on November 04, 2012, 10:16:29 AM
Post by: hillbilli on November 04, 2012, 12:40:35 PM