Boring sighting puzzle.

[jm22250]

I recently bore sighted a rifle I made up with a Howa 1500 barreled action, heavy stainless barrel, in 308
I'm using a Bushnel bore sighter with arbors. Have used it for years and have had no problems. When I bore sight this gun it shoots about 1 foot high at 100yds. Windage is ok. I put the bore sighter on 2 other guns that I know are right on, and the bore sighter is right on. I don't know what is going on. Any ideas? When I adjusted the scope down it did shoot a tight group. Have only shot a few groups.
John Miller

 

[dmickey]

Bore sighting is inconsistent at best. I have put scopes on my nine Remington 40XB's and some of them missed the paper at 100 yards and some of them were on paper! Seems to have to do with the trajectory of the individual cartridges. Best bet is to start shooting at 25 yards and work out from there. I've seen some people bring a bore sighted rifle to the range and start right out at 150 yards (longest target at that particular range.) Didn't hit the target but that didn't stop him. I finally suggested that he start at 25 yards. After that it took only a few shots and then he was hitting where he wanted! Bore sighting is not magic! :

 

[Minesweeper3433]

Our unit wanted me to boresight all the M4s in the inventory with one of the laser units. Only a very small fraction of the carbines where close. From then on I would set up the upper reciever assmeblies on a rest and look down the bore at a dot on the wall tapped in place and line the sight and bore with the dot. Actually worked better than the lazer.

 

[queen_stick]

Our unit wanted me to boresight all the M4s in the inventory with one of the laser units. Only a very small fraction of the carbines where close. From then on I would set up the upper reciever assmeblies on a rest and look down the bore at a dot on the wall tapped in place and line the sight and bore with the dot. Actually worked better than the lazer.

That's what I do... takes 5 minutes, and costs nothing.

I've used two different bore sighters... both have been in the box for a long time, and will probably remain there.

Some guns, like the 10/22's, can't be bore sighted because you can't see down the bore... I just set up a target at 10 yards or less and start spraying lead...

 

[Minesweeper3433]

Our unit wanted me to boresight all the M4s in the inventory with one of the laser units. Only a very small fraction of the carbines where close. From then on I would set up the upper reciever assmeblies on a rest and look down the bore at a dot on the wall tapped in place and line the sight and bore with the dot. Actually worked better than the lazer.

That's what I do... takes 5 minutes, and costs nothing.

I've used two different bore sighters... both have been in the box for a long time, and will probably remain there.

Some guns, like the 10/22's, can't be bore sighted because you can't see down the bore... I just set up a target at 10 yards or less and start spraying lead...

Not to mention half the fun is shooting the guns. I hate it when I see a gun get sold to a guy that is going to hang it on a wall next to a mount that he purchased at a yardsale. Sighting in finding the right load and practicing are the biggest reasons for buying any gun in the first place. Its just fun