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Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/04/2007 at 00:50
jackG View Drop Down
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For open country hunting, how high do you guys want your rifle to shoot at the maximum arc?  I'm familiar with the concept of MPBR and the notion of keeping the point of impact in a 6 or 8" diameter circle.  A hunting aqaintance uses a Swarovski, with a mil dot type reticle, and insists that any rifle should be sighted to strike the bull at 100 yards, that is no added elevation.   Compensation for increased range should be made with the reticle.

 

I shoot with a plex type scope reticle which precludes that.  I sighted nearly 3" high at a 100 yards, using a 270 WSM and 140 gr bullets with a nominal velocity of 3200 fps.  In low light I had one shot cleanly miss high at around 125 yards of so.  The animal stood so I had a followup opportunity.  I made a big deal of aiming at the boiler room center line. The shot was still high enough on the body to disrupt the spine function.  It hit high in the lungs.   All other shots out to over 300 yards were just about where I aimed.   I suspect the one high shot was somelthing I did, because all the others were nearly perfect.  As noted, the light was fading and I was in a canyon. 

 

The quesiton is, is 3" high, too high for that set up? 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/04/2007 at 01:50
www.technika.nu View Drop Down
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I like to be so well sightet in that I can shoot a brainshot up to hundred yards.

But shooting really precisice shoots with the gun sighted in 3" high is very difficult, and when it's dark it's even more problematic.

 

On the other hand the mildot, that not is designed as a hold over reticle but as a measurement reticle for reiciving targetinformation or giving target information to others in the same military role. Any reticle used for compensation together with a second plane scope is difficult, someday you will have it at the wrong magnification and make an ugly shot.

 

I prefers the elevation turrets, so the gun is sighted in at hundred yards, and if I want to shoots at 300 or whatever I make a fast adjustment. Some people say that the elevation turrets are to slow, but I cannot agree with that as a 300 yard shot not really is driven game and in order to make a good shot some time have to be spent anyway.

 

 

Regards TEchnika

 

 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/04/2007 at 09:07
RONK View Drop Down
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 I generally agree with technika, although some on this site make a very good case for dialing elevation by using a dedicated BDC, as opposed to dailing in by counting clicks, which I never found to be troublesome. I believe Rifle Dude is a proponent of BDCs, and he has me reconsidering their speed and simplicity.

 I suspect the bad shot you made in bad light was perhaps the result of you using the top of the lower post as your aiming point in the excitement? Not a real rare occurrence, especially in low light. If you have an accurate rifle, you didn't hit an obstruction between you and the animal and you were holding solid, nothing else I can think of at the moment would explain it. Three inches high at 100 is still only three and a fraction high at 125, and well within the kill zone of most big game.

 BTW you didn't really specify the size of the animal, which is a very important consideration in determining what you decide to use in determining the parameters of your particular MPBR.

 If you want to dial, a 100 yard zero is generally an accepted starting point for tactical shooters. I usually zero my hunting rifles about 3"high @100 and don't worry about it too much other than holding a touch low at mid-range and a touch high at 300. I try to limit my shots at game to about 300yards, depending on circumstances.

 Incidently the spinal cord on a deer or elk is almost halfway down the animal between the shoulders, much lower there than many hunters think .



Edited by RONK
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/04/2007 at 09:37
Dale Clifford View Drop Down
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here is your data for the load and 8 inc zone

 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/04/2007 at 12:23
RONK View Drop Down
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Dale Clifford- good information there, but in my opinion an 8- inch " Vital Zone Radius" (16 inch diameter ) kill zone is way too big for anything smaller than moose. A hit 8 inches above or below a center-chest hold on a deer or antelope will almost always be a problem. A 4- inch radius would be more realistic for those critters.

  Good advice too, on checking out your scope thoroughly at the range so you know exactly what it will do if you choose to dial.



Edited by RONK
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/04/2007 at 14:04
www.technika.nu View Drop Down
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If there is going to be made shots on animals the scope has to be sighted in.

and if there is shots going to be made at 300 yards, the scope has to be tried at 300 yards.

That is regardless of what sightingmethod that is used.

 

Regards Technika

 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/04/2007 at 16:50
RONK View Drop Down
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Originally posted by www.technika.nu www.technika.nu wrote:

If there is going to be made shots on animals the scope has to be sighted in.

and if there is shots going to be made at 300 yards, the scope has to be tried at 300 yards.

That is regardless of what sightingmethod that is used.

 

Regards Technika

 

  Of course a scope has to be sighted in. I don't think that was ever brought into question. You are correct, though, that a hunter must know where his bullet will land at whatever distance he is going to be shooting, and be able to adjust his hold or his sight/scope settings accordingly. Regular range practice and careful and accurate note-keeping will accomplish this quickly.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/04/2007 at 20:30
Dale Clifford View Drop Down
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8 inch is the size of a plastic coke bottle, a paper plate, and the A zone on an IPSC target  and I'll take it from anything from pd thru elephant.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 02:20
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I zero at 200yds, which is about 2 inches a 100 yds. I have allways used the holdover method on shots of more then 250 yds. I would be reluctant to use the dialing in method, because in the heat of the battle a person can forget to dial back again.

I remember the days of iron sights when my father would allways miss the buck because the sights were still on 300 yds (or whatever) from the previous one and so on.

So set your scope, and practise the holdover. At what distance you zero depends on your longest expected shots.

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 04:44
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I'm with Dale on the paper plate and our friend from the southern hemisphere, 8shots, on holdover. I have never had a problem with 2" high @100 yards and holdover. I don't shoot at big game over 400 yards, though.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 06:46
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I use a mildot I sight my rifle in @ 300 yrds, anything under 300 yrds I use the first dot over the crosshairs, I aint missed yet.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 11:03
Dale Clifford View Drop Down
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using a constant size for the target, has an advantage in that it allows the shooter to change the other variable of time on sight depending on the distance. after 200 yards some type of stationary rest is. of course desirable, and the more stable the platform. In competitive shooting it allows one to get the shot off sooner, against time pressure and in hunting gives a little more peace of mind.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 18:02
RONK View Drop Down
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Originally posted by Dale Clifford Dale Clifford wrote:

8 inch is the size of a plastic coke bottle, a paper plate, and the A zone on an IPSC target  and I'll take it from anything from pd thru elephant.

 You won't hit either very often if you use the trajectory table you provided jackG for his handloads. This is because, as I've mentioned earlier, the Vital Zone on the twelfh line of your chart lists an 8-inch RADIUS as the target size. That is not a paper plate. That is a garbage can lid, and it seriously skews the rest of the trajectory data on that chart.



Edited by RONK
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 18:26
Dale Clifford View Drop Down
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I think JBM uses this as center as the data for 400 yds shows -7.3 which would be in the 8 in. area. Not sure how your reading the tables, unless as the diameter.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 18:34
Dale Clifford View Drop Down
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even a 4 inch would put it only slightly out at 400 and 9 in -- with a still pbr of 300 yds. pretty damn good ballistics. (used a G1 would propably even better with G6)

 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 18:39
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Know your cartridge.

 

Know your rifle.

 

Know your reticle.

 

Last and not least.................................................know yourself.

If you didn't shoot it in practice you never shoot it in the field.

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 18:43
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Originally posted by Mike McDonald Mike McDonald wrote:

Know your cartridge.

 

Know your rifle.

 

Know your reticle.

 

Last and not least.................................................know yourself.

If you didn't shoot it in practice you never shoot it in the field.

 

Sound wisdom, Mr Mike.

As Shakespere would say "To thine own self (and rifle) be true".



Edited by cheaptrick
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 18:47
RONK View Drop Down
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 Minus 7.3 inches is already 3.3 inches below the bottom edge of your theoretical 8-inch target, using a center hold, and I consider the 350 yard Maximum Point Blank Range in your second chart to be a great deal different than the 504 yard one shown in your first chart.

 I was only trying to point out that the first chart would not allow you to make center-hold, on-target hits with that load, on an 8-inch target, as you stated. A 16 inch target,yes, but not an 8-inch one.

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 18:58
RONK View Drop Down
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Originally posted by cheaptrick cheaptrick wrote:

Originally posted by Mike McDonald Mike McDonald wrote:

Know your cartridge.

 

Know your rifle.

 

Know your reticle.

 

Last and not least.................................................know yourself.

If you didn't shoot it in practice you never shoot it in the field.

 

Sound wisdom, Mr Mike.

As Shakespere would say "To thine own self (and rifle) be true".

 Mark- I don't know if Shakespeare would have said that, but I'm quite sure he would have spelled his name correctly if he had.

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 19:01
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Oh boy. I stand corrected, Sir.

 

"Spell check, spell check, my kingdom for a spell check"........ 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 21:03
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Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 22:45
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jackG.....................For any open country hunting, I zero my 300WSM in at 300 yards. Your 270 WSM is slightly better in the flatter shooting dept. With my plex recticle, a 300 yard zero will eliminate as much guess work as possible, in hold under at the shorter ranges or hold over out to 400 yards.........If you know your velocities by using a chrono, your bullet`s BC, which in turn determines the bullet`s trajectory and hunt with a range finder, you shouldn`t have any problems.    
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/05/2007 at 23:29
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+1 on the advice from Big Squeeze.  I love my mil-dot for long range shooting, but for straight simplicity, you can't go wrong with his advice.  I have sighted my 270 at 300 yards since I started hunting.  My 300 win mag is sighted in much farther out for long range.  For big game hunting though, 300 yard zero is probably the most practical.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/06/2007 at 02:05
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I always sight-in for the MPBR, but i like to refer to it as the CMPBR. C=CONSERVATIVE, such that the MPBR should be calculated for 3/4ths the tgt. size--no more, and sometimes less--maybe 1/2 would be better. If u don't u're gonna shoot over some tgts. (close range), and under some (LR). I apply any reticle that has more than 1 stadia as a ballistic and rangefinding reticle, as it may come in handy (often for spot and stalk coyotes). I prefer BDC reticles (even simple plex), as they are faster for me to apply in the field. A perfect example of this happened just this year. We were hunting antelope in WY, and had an opportunity on a doe. She was very nervous tho, as they'd been pushed hard that week. She would run, and stop for a few seconds then run and stop again. Every time she stopped my partner would call out the lasered range to us, and it was a simple matter of glancing up at my range sticker on the inside of my Butler Creek scope cap cover to see what the dope was, no movement necessary, no loss of cheek weld, etc. Just my system.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: November/06/2007 at 08:44
Dale Clifford View Drop Down
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ronk -- yea your math is correct, i was thinking more of a statistical 8 in kill zone. and holding in that.

 

got to go back and see why one has a 7.3 and the other has a 9 though

 

a question that jumps up at this point in these discussions:

 

say a ballistic chart will show x amount of high of impact at using -- say 200 yds, but you are only shooting at 100 yds, (set scope to shoot 2 in high at 100 for 200 yd poi).

assuming correct scope tracking and stabilized round, with what degree of certainty can the projected data through the ballistic profile be trusted???

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