max point blank range
10-29-2005, 12:22 PM
#1
Thread Starter
Join Date: Oct 2005
Posts: 117
max point blank range
Can anyone tell me the maximum point blank range for a browning abolt with a 22 inch barrel shooting 140 grain winchester ballistic silvertips and how high i need to adjust it at 100 yards. How do you figure this out so i can do it with my other rifles.
zesterhouse
zesterhouse
10-29-2005, 12:43 PM
#3
Giant Nontypical
Join Date: Feb 2003
Location: fort mcmurray alberta canada
Posts: 5,667
RE: max point blank range
To start with what is the maximum distance that you want the bullet to be above or below the line of sight?What is the exact velocity of the load out of your rifle?What is the ballistic co-efficient of the bullet?What is the height of your crosshairs above the center of the bore?Once you have all the required data,you can estimate the maximum point blank range and the 100 yard point of impact.However remember that this is only an estimate and the actualpoint of impact may vary by several inches at 300 yards.
10-29-2005, 05:25 PM
#4
Join Date: Mar 2005
Location: Colorado
Posts: 4,127
RE: max point blank range
Go to a ballistics program like Exbal or Infinity. You can plug in all the variables - even elevation and the height of the scope above the bore - then tweak the chart until you get what you want. With most "standard" calibers, I have my guns sighted in 3" high at 100 yards. The fast ones are still a little high at 300 yards - the slower ones are three or four inches low at 300 yards. But it allows me to hold on the chest of a big game animal out to 300 yards without much thought. This is about as far as most people should be shooting anyway.
10-29-2005, 07:22 PM
#7
Boone & Crockett
Join Date: Feb 2003
Posts: 10,679
RE: max point blank range
I do not like to use the entire target size to figure my MPBR. I like to leave some room for error. By this I mean if I am shooting at a 12" diameter target you got six inches above and six inches below center. I would rather figure my MPBR for a target half the size. So I use three inches above and three inches below line of sight as my MPBR. This gives me room for error and still make a killing shot on an animal.
If you use the entire targets diameter then you can not make any mistakes at the bullets highest point or its maximum range/ lowest point. If you do something like flinch ever so slightly then your bullet will be off the mark and you get a wounded animal. Also you gotta figure that you, nor your rifle are going to be able to put every bullet into a single hole at all distances you may be shooting. You gotta leave room for things effecting the bullet that you can not control such as barrel vibrations, differances in velocity between shots, wind speed and direction, temperature, weather, altitude, etc...
Out of a 22 inch barrel with that bullet we will figure about 2850 fps muzzle velocity cause you aint gonna get the 3040 advertised. Being that you aren't shooting with a test barrel and you lost 2 inches.
Sight in to be hitting 2.5 inches high at 100 yards. That should put you three inches high at about 135 yards, back to zero at about 240 yards and about 3 inches low at 285 yards and at 300 yards about 4.5 incles low. Sighted in this way you will be able to hold on a deer out to almost 300 yards and not worry about any hold over.
If you use the entire targets diameter then you can not make any mistakes at the bullets highest point or its maximum range/ lowest point. If you do something like flinch ever so slightly then your bullet will be off the mark and you get a wounded animal. Also you gotta figure that you, nor your rifle are going to be able to put every bullet into a single hole at all distances you may be shooting. You gotta leave room for things effecting the bullet that you can not control such as barrel vibrations, differances in velocity between shots, wind speed and direction, temperature, weather, altitude, etc...
Out of a 22 inch barrel with that bullet we will figure about 2850 fps muzzle velocity cause you aint gonna get the 3040 advertised. Being that you aren't shooting with a test barrel and you lost 2 inches.
Sight in to be hitting 2.5 inches high at 100 yards. That should put you three inches high at about 135 yards, back to zero at about 240 yards and about 3 inches low at 285 yards and at 300 yards about 4.5 incles low. Sighted in this way you will be able to hold on a deer out to almost 300 yards and not worry about any hold over.
10-30-2005, 08:20 AM
#8
Giant Nontypical
Join Date: Feb 2003
Location: Texas - BUT NOW in Madison County, NY
Posts: 6,270
RE: max point blank range
"To start with what is the maximum distance that you want the bullet to be above or below the line of sight?"
In addition to this, HOW MUCH above & below the LOS do you desire? This is based on the game you plan to shoot! For deer, I don't want the bullet to be much over 4" above or below the center hold. But for an elk or moose, you can at least double that and still make a vital hit using a center hold!
And, as stubblejumper says, you have to know the MV and ballistic coefficient of your ammo/rifle combination, plus the distance from the center of the bore to the optical centerline of your scope.
When you have this information, go to http://www.handloads.com/calc/and play with the zeroing distances to get the figures you are looking for.
BTW, barrel length is not germaine to this particular question. You MUST KNOW the actual, exact MV of the load you are firing regardless of barrel length.
In addition to this, HOW MUCH above & below the LOS do you desire? This is based on the game you plan to shoot! For deer, I don't want the bullet to be much over 4" above or below the center hold. But for an elk or moose, you can at least double that and still make a vital hit using a center hold!
And, as stubblejumper says, you have to know the MV and ballistic coefficient of your ammo/rifle combination, plus the distance from the center of the bore to the optical centerline of your scope.
When you have this information, go to http://www.handloads.com/calc/and play with the zeroing distances to get the figures you are looking for.
BTW, barrel length is not germaine to this particular question. You MUST KNOW the actual, exact MV of the load you are firing regardless of barrel length.
10-31-2005, 03:23 AM
#10
Giant Nontypical
Join Date: Feb 2003
Location: Port Neches, Texas
Posts: 5,514
RE: max point blank range
ORIGINAL: Mr. Zesterhouse
I'll be hunting whitetail so six inches above or below is all i want.
thanks
zesterhouse
I'll be hunting whitetail so six inches above or below is all i want.
thanks
zesterhouse
!I wouldn't go more than a 3" MPBR! And don't forget the practice at that! Just because the MPBR is X inches at X yards, doesn't make up for the hours of practice required for good shooting!