Sighting in trouble?
09-03-2006, 08:36 PM
#1
Thread Starter
Join Date: Jan 2006
Location:
Posts: 195
Sighting in trouble?
I went and shot my .308 today. At 50 yards I was hitting about an inch high and all fives shots were touching. I was happy and thought, if I'm an inch high then I may be dead bull at 100 yards. No, I was hitting 3 inches low at 100 yards and the fives shot were almost all touching.Why would I be hitting so low changing 50 to 100 yards? Should I sight in for 100? Would that make me 4 inches high at 50? I only had one box of shells and it was federal fusion 150 gr.. Should I test different ammo? Please, any advice would be welcome, thanks!!
09-03-2006, 08:59 PM
#2
Join Date: Jul 2006
Location:
Posts: 218
RE: Sighting in trouble?
Sorry Chuck,
Something don't add. But yes sight in at 100 or farther. Honestly when you sight in at a given range, you can only guess where it will hit at another, educated guess but guess. Want to know where hit 300 shoot 300, 50 shoot 50.
Something don't add. But yes sight in at 100 or farther. Honestly when you sight in at a given range, you can only guess where it will hit at another, educated guess but guess. Want to know where hit 300 shoot 300, 50 shoot 50.
09-03-2006, 09:04 PM
#3
Giant Nontypical
Join Date: Feb 2003
Location: Port Neches, Texas
Posts: 5,514
RE: Sighting in trouble?
That sounded a little strange, so I pulled out the trusty old book.
On "paper" if you are an inch high at 50 yards,you should be about 2.5 inchs high at 100 yards. With a 100 yard zero, you should be about 1/4 of an inch high at 50.
Granted, this is "book" stuff, so there is a little wiggle room. But if you are high at 50, you should be higher at 100, not lower.
On "paper" if you are an inch high at 50 yards,you should be about 2.5 inchs high at 100 yards. With a 100 yard zero, you should be about 1/4 of an inch high at 50.
Granted, this is "book" stuff, so there is a little wiggle room. But if you are high at 50, you should be higher at 100, not lower.
09-03-2006, 09:08 PM
#4
Typical Buck
Join Date: Jul 2006
Location:
Posts: 781
RE: Sighting in trouble?
The 30-06 is a similar round. If mine is dead at 150, it's an inch high at 100 and right on at 50 also. So if you sighted dead on at 50, you'd be 1 inch high at 100. something is really wrong with this. An inch high at fifty would be around 2-3 in high at 100.
What kind of scope you have?
What kind of scope you have?
09-03-2006, 09:29 PM
#6
Giant Nontypical
Join Date: Feb 2003
Location: fort mcmurray alberta canada
Posts: 5,667
RE: Sighting in trouble?
The 30-06 is a similar round. If mine is dead at 150, it's an inch high at 100 and right on at 50 also. So if you sighted dead on at 50, you'd be 1 inch high at 100. something is really wrong with this. An inch high at fifty would be around 2-3 in high at 100.
09-03-2006, 09:36 PM
#7
Join Date: Mar 2005
Location: Colorado
Posts: 4,127
RE: Sighting in trouble?
The only way this would be possible is if your ammo is only loaded to about 1400 fps.And this would be with thelow rings - only 1.5" above the center of the bore. Taller rings would only cause the point of impact to be higher at 100 yards with a 50 yard zero. Something just isn't right here.
09-03-2006, 09:50 PM
#8
Giant Nontypical
Join Date: Feb 2003
Location: Port Neches, Texas
Posts: 5,514
RE: Sighting in trouble?
With a 5 shot group, "all touching" would be a 1.5 inch group maximum!
At 1 inch high at 50 yards, moving out to 100 yards, the POI shifted 5 to 6 inches, but held the group! Amazing!
It could happen, but the scope would likely have to be moved, and then retightened, or else the group would have started to open up.
A hot barrel could account for some of the shift, or the scope moved, but then stayed put throughout the second group.
If everything is tight on the scope you've got a big problem, and I would not trust the scope for hunting!
At 1 inch high at 50 yards, moving out to 100 yards, the POI shifted 5 to 6 inches, but held the group! Amazing!
It could happen, but the scope would likely have to be moved, and then retightened, or else the group would have started to open up.
A hot barrel could account for some of the shift, or the scope moved, but then stayed put throughout the second group.
If everything is tight on the scope you've got a big problem, and I would not trust the scope for hunting!
09-03-2006, 09:59 PM
#9
Giant Nontypical
Join Date: Feb 2003
Location: fort mcmurray alberta canada
Posts: 5,667
RE: Sighting in trouble?
The only way this would be possible is if your ammo is only loaded to about 1400 fps.And this would be with thelow rings - only 1.5" above the center of the bore. Taller rings would only cause the point of impact to be higher at 100 yards with a 50 yard zero. Something just isn't right here.
09-03-2006, 09:59 PM
#10
Typical Buck
Join Date: Jul 2006
Location:
Posts: 781
RE: Sighting in trouble?
ORIGINAL: stubblejumper
Of course ring heightis a big factorhere,as is the particular load used.
The 30-06 is a similar round. If mine is dead at 150, it's an inch high at 100 and right on at 50 also. So if you sighted dead on at 50, you'd be 1 inch high at 100. something is really wrong with this. An inch high at fifty would be around 2-3 in high at 100.
