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Discussion Starter #1
Ok, simple question. I'm shooting a .308 mauser, Federal Premium Nosler Partition's, 180 gr. If i sight in at 2in. high at 25 yds., what would be the corresponding trajectory rate for 100 & 200 yds? Any feedback would be of help. Also, what would be the same for dead on at 50? Thanks, Topknot-less......
 

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Beartooth Regular
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lepirt,
Using the ballistics calculator on this web site, I found that sighting in 2 inches high at 25 yds will put you over 10" high at 100 yds and over 14" high at 200, WAY too high! There are a lot of variables, but in any scenario 2" high at 25yds is
too high.
I use a .308 with 180 gr bullets sometimes too, and I start by sighting in dead on at 25yds. Then with some minor tweaking this will put me about 2.5" high at 100 and dead on again at 200yds. I always end up fine tuning my zero at the longest range possible. But a dead on zero at 25yds is a good place to start. My 180gr loads clock at 2560fps.
You really have to try it in your rifle, because scope height and the actual velocity your rifle acheives will vary. Believe it or not, scope height will have more of an impact on sighting in than slight velocity changes.

Let us know how things are coming along! ID
 

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Beartooth Regular
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Hi, lepirt:
Looks like you have to sight in at short range. That's not the best because what the computer says doesn't anyways happen on the range, sometimes it's all you can do. It's not really that simple, since you didn't say if you're shooting with irons or a scope. Anyhow, let's give it a try. Now 2" high at 25 yd. is away too high, that gives a zero at 440 yd. with a scope 1.5" above the bore and a zero at 360 yd. with irons 0.7" above the bore.
Scope at 100yd = +10.5", at 200 yd. = +16.6"
Irons at 100yd = +8.0", at 200 yd. = +10.7"

Dead on at 50 is better. With a scope you're back on again at 110 yd. and -4.2" at 200 yd. With irons your trajectory peaks at 50 yd., -0.7" at 100 yd. and -6.6" at 200 yd.

Try for +1.6" at 50 yd. That should put you +2.6" at 100 yd. and dead on at 200yd.

May I suggest a couple of ballistics programs you can play with yourself? You can download PointBlank at http://www.huntingnut.com/pointblank.html or you can get to JBM by clicking on Ballistician's Corner on the left side of this page.

Don't be afraid to holler if you have any problems.

Bye
Jack
 

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Discussion Starter #4
Thanks for the reply, gentlemen. I'm sorry i didn't add that i'm a iron shooter, kinda partial to them since i've strictly been a muzzleloader for 20 years. Almost changed to a scope years ago, but thank god, Colorado kept the regs with no scopes. The mauser i'm shooting is vintage 1938 and has a Lyman peep on it, so wish me luck! I think i'll sight dead on at 50 (i have enough room for that yardage), and go from there. Keep ya posted, headin' out for the big timber in 2 weeks to chase them wiley wapiti's........
 

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Nawth East Moderatah
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I've found that with my M1a and my Winchester 100 that if I'm dead on at 100, I'll be almost exactly 1.5-2" low at 200.
That is using a 165Hornaday or the Nosler 168 match.;)
 
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