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corvette8n
12-03-2006, 05:26 PM
I have bore sighted dozens of rifles using my Bushnell optic type boresighter, but when I tried my own savage 110 in .308 it don't work. Boresighted it 1 in high in the optics, went to the range and it shot a foot high at 100 yards, came back and threw the borsesighter back on and it read 1 in high, so I ripped off the scope and mount and used weaver bases instead of the Leupold base. The scope is a Burris 3x9 ballisticplex. Boresighted right on back out to the range and a foot high, change scopes and still a foot high. I never had this problem before on any rifle whether mine or for friends, once I got a rifle boresighted it usually took a couple of clicks to get it perfect at 100 yards.
Is my barrel crooked? or not screwed on correctly?. headspace measures ok with headspace guage. I bought this gun used because it is a lefty bolt action, my first.
any suggesions.?:(

Char-Gar
12-03-2006, 06:39 PM
I have a suggestion.. shoot the rifle and see how it groups. If it groups well, forget about why your gizmo won't work on this rifle. Once the rifle is sighted in, it doesn't matter how it got there.

I have lived my entire life without one of these gizmos. I can jerk the bolk, center the target bull in the barrel by eye, and adjust the cross hairs to get me on paper. I then use the sight adjustments to finish the task. I could never justify the expenditure of cash to get me six to seven inches closer.

felix
12-03-2006, 06:58 PM
Sight the gun in with only one shot! Get a big piece of paper, with a large dot in the center. Bore sight by eyeball the scope. Shoot the gun at the large dot. Hold the gun at the large dot without moving it. Move the crosshairs to where the bullet/boolit hole is. You are done good enough for tin cans at that distance. To refine for shotgun shells, repeat the same process. ... felix

carpetman
12-03-2006, 08:35 PM
When bore sighting use a deprimed case and sight through the flash hole. This smaller aperture will get you even closer.

felix
12-03-2006, 09:14 PM
Very good idea! Never thought of that. Shame on me. ... felix

PatMarlin
12-03-2006, 09:18 PM
When bore sighting use a deprimed case and sight through the flash hole. This smaller aperture will get you even closer.

Great- just when I thought I knew it all.. :roll:

.....................:mrgreen:

Char-Gar
12-03-2006, 09:19 PM
Felix et al... years ago an old German gunsmith showed me how they sight in a rifle in Germany. He used sand bags and fired one shot at 25 yards. He then braced the rifle with sand bags, looked through the scope and moved the cross hairs until they centered on the lone bullet hole. So sighted, the rifle as dead on at most hunting ranges.

PatMarlin
12-03-2006, 09:23 PM
I agree with Charles on justifying the cost of a bore sighter. Never had a rifle I couldn't site in with a few shots, unless somethin' wrong with the scope.

Levers are a little more difficult if you can't remove the bolt of course. I'd just dump the boresighter and eBay it.. :mrgreen:

felix
12-03-2006, 09:31 PM
Sandbags? Would be welcomed for such a chore. Or, a vise on the back of a truck to hold the gun/barrel down while moving the scope. In practice with no support, the best I can do is get to beer can targeting. The gun moves just enough to make another go-around almost necessary. ... felix

Char-Gar
12-03-2006, 09:38 PM
Pat.. On levers I shoot as some object on the 50 yard berm and watch the dust. I can get a good idea of where it is and how far to adjust.. click..click. click...etc and shoot again...another series of clicks and I am good to go on paper.

I remember when these optical "collimaters" first came out back in the early 60's. Gun stores bought them so when they mounted scopes, they could give them to the customer close enough to be on paper. I guess folks have become dependent on them since those times.

Back then, It was surprising how few folks knew how to sight in a rifle. Our gun club range was private and behind a locked gate. Two weekend before deer season, we opened the gate so the public could sight in. However we made certain a membeer was there anytime the gate was open. I spent all day there and most folks could not sight in their rifles without help of some kind. Many of them just handed me their rifles and ammo and I did the sighting in for them.

A local indoor range now has a computor set up whereby a fellow can sight his rifle in at 25 yards and get trajectory for any load out to 600 yards. Come deer season they do a land office business... Many people just drop their rifles off and the range charges a fee to sight them in and give them a print out. I guess nothing has really changed.

44man
12-03-2006, 10:06 PM
I never understood how such a simple process can be so hard for a lot of hunters! How many are out there trying to shoot deer with a new rifle that some store used one of those gadgets on? Easiest way on earth is to look through the bore. I had a slice of mirror I used in lever and pump guns but lost it. I had to sight one yesterday for a friend after I installed a scope. I just went to 25 yd's, shot one and dialed it into the bull. Back at 100 I was only a few inches off.
One thing I have found a lot of lately are the scopes that don't follow the clicks as marked. Says 1/4 minute and if moved 4 clicks, the POI moves 3", drives me to drink!

Blackwater
12-03-2006, 11:51 PM
Corvette, this is just a guess, but I'm thinking that the reason your rifle shot higher than your bore sighter indicated is that there's some upward forend pressure on your barrel by the stock. Rifle barrels "bounce" away from any hard contact when fired. Thus, if your rifle has contact at the forend, it'd shoot higher than the barrel's pointed when at rest. Make sense?

Don't know this is the case, but you may want to check it. If the stock is a synthetic, and stable when damp or dry, cool or hot, I wouldn't sweat it if it's shooting good groups. If not shooting that well, you may want to file or rasp away any contact of the forend to the barrel, and see if that makes it shoot any better. If it shoots worse that way, a piece of flat plastic, cut to @ 1/2"x1/2" or so, and placed back where the contact was, should get it back to where it's shooting now, if that's where you get your best groups. Experiment with different pieces of flat plastic laying around the house until you find the "magic" one that makes your gun shoot its best.

This is a very easy "accuracy job" you can do to any rifle. Any barrel contact with the stock will affect a rifle's grouping ability, and sometimes some rifles shoot better with some forend pressure. If the stock's wood, and therefore subject to swell or shrink with changes in moisture content due to humidity or being caught in the rain, I'd not myself want any forend pressure, even though many did just that in bygone days. If it's a synthetic, I'd have no problem with forend pressure if that makes the rifle shoot better. FWIW?

Oh yeah! Those "bore sighting" instruments simply CAN'T work for anything more than rough signting, since in any rifle, you'll almost always get different POI when you change bullet wt., load, or factory brand of ammo. This is because barrels vibrate, and different bullets and loads leave the barrel at different points in its vibration cycle. Make sense? Expecting a bore sighter to "zero" a rifle just isn't destined to lead to anything but heartache one day, even if it "often" works. You've got to shoot 'em to find out where your chosen loads will hit. Too many variables are at work to merely use at rest barrel direction for your POI. WAY too many.

slughammer
12-04-2006, 06:04 PM
I’d shoot the rifle at different distances and see if POI changes more than it should. 50, 100, 200 if possible. If POI is consistent, then adjust the scope. If the scope runs out of adjustment, then a special set of bases will be needed to compensate.

If you shoot at 50, 100 and 200 and the POI changes, then look at a barrel problem.

I have a laser bore sighter, and find it a great tool to have around for occasional use. Just like your optical one; once you own it and know how to use it, I see no need to stop.

snowtigger
12-05-2006, 02:05 AM
When I install a new scope, I usually start at 25 FEET. This will always get the first shot on an 8 1/2" X 11" target. I zero it horizontally and not too much high vertically. I then move it out to 100 yards, and proceed from there. It works for me.
However, today I deviated from that as there were several people at the range I went to. I started at 100 yards. MISTAKE!!
Without a spotter, it took me Half a dozen shots to find the paper. After that it was business as usual.
Boy this .280 is going to be a tack driver!!The last group I shot had 3 within a half inch. The fourth opened it up to about .750" I am going to blame the lack of light for the fifth one, it opened the group up to 1 1/2 inches. Can I call that one a "flyer"?

PatMarlin
12-05-2006, 03:03 AM
My neighbor has a 32 Winchester, that was her grandfathers, and NO ONE including gramps had ever been able to sight the rifle in. Hunted with it for years.

The greatgrandson was out shooting it with me, and I noticed the darn thing was way off, so I sighted it in, and the thing was a tack driver. THe kid was walking on clouds when he finally realized he could shoot. He had also hunted with it, and never got a deer. Missed every time.

His mom told me know one in the whole family had ever got the rifle to shoot worth a damn... :roll: :mrgreen: