Sighting In


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MarkDido
June 1, 2003, 02:45 AM
I'm new to long guns and I need to sight in my Marlin Model 60's iron sights and an inexpensive Bushnell scope.

Is there a preferred type of gun rest for this? I've seen many examples on several sights of sand filled bags, and also of rigid rests.

A quick course on "Sighting In 101" would be apprecieted@

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critter
June 1, 2003, 10:53 AM
I'll give it a 'shot'. First-rests. Anything that can be used has been used. The idea is to get the rifle rock-solid steady in a repeatable position for each shot. Triggering thshot should not disturb the sight alignment/sight picture-of course the recoil will. That is so that you KNOW where the sights were pointed when the shot broke. Good sandbags work well for this.

With iron sights or a scope, ammo and time will be saved if the gun is 'bore sighted'. That is, the sights are aligned with the bore of the gun. That can be done (very cheaply and often free) by your 'smith with any of various devices. This step is NOT necessary.

Iron sights. Fire a shot as outlined above-2 or 3 are better. Fire at a target with a good sighting feature such as a well defined circle and usually begin at 25 yards or so. If the shots do not coencide with the point of aim, move the rear sight IN THE SAME DIRECTION you want to move the bullet strike. Move a little, shoot again, move a little and shoot till they coencide. NOW move the target to 100 yds or so and repeat the process. You should be good to go at this point.

Scope: same as above but the little knobs on the scope will tell you which way to turn them to move the bullet strike and the literature with it will tell you how much. Usually a 'click' will be 1/4" or so AT A HUNDRED YARDS. Again, it is a shoot and try deal.

Good luck with your sight in. It in itself is a fun, rewarding and educational experience.

Mal H
June 1, 2003, 11:19 AM
There is a well known technique that will get a rifle sighted in with a lot less cartridges wasted than the normal scope adjusting procedure.

Be sure you have a solid rest just as you asked about. There are so many different possibilities for a rifle rest. Go with the cheapest first - sand bags. Some rests and supports can cost more than your rifle and scope combo.

Fire a group of 3 from your rest at a small bullseye and make them as accurate as you can - take your time. Assuming the group isn't on the bullseye (if it is, you're done, obviously), put the crosshairs on the center of the group and holding the rifle as solid as possible (you might want to weight down the rifle or have someone help hold it steady), adjust the windage and elevation of the scope until the crosshairs are now on the bullseye. Then you can fine adjust the scope with a few more groups. In one short step, you've got the scope very close to the target.

Note that the final group may not be exactly on the bullseye if you are adjusting for, say, a 100 yard dead on, but your sighting target is at 50 yards. Adjust your POI while sighting in according to the end result you're seeking.

Guyon
June 1, 2003, 11:25 AM
Of course, you won't be able to use both the iron sights and the scope simultaneously, so I'm guessing you'll want to sight in your iron sights, then mount your scope, and then sight in the scope.

It's a .22 semi-auto which makes it a little difficult to "eyeball" as far as bore sighting. However, ammo expense is not a factor here, so rather than buying an expensive laser bore sighter, I'd go with critter's and Mal's recommendations and just start shooting at short distances (maybe 15-25 yards) and get the gun shooting to point of aim. Then you can increase the distance out further (40-50 yards) and make any adjustments that are necessary. Or move it on out to 100 yards and do the same. This method will work for both the iron sights and the scope, though the scope might be a little more difficult to get on paper at first.

With a .22, recoil is not much of a factor, but you still would be better off with two sandbags so that you can secure both ends of the rifle and be sure of POA when you pull the trigger. Sand bags are pretty easy to make, and I have one large homemade one that I use a lot. I also have a set of leather Protektor bags that are well made and durable. You could also look into an even nicer shooting rest if you want to spend some $$$. To save some cash here, you might look on eBay.

hps1
June 1, 2003, 08:02 PM
put the crosshairs on the center of the group and holding the rifle as solid as possible (you might want to weight down the rifle or have someone help hold it steady), adjust the windage and elevation of the scope until the crosshairs are now on the bullseye.

This procedure works great, biggest problem I have with it is remembering which way to go. The above procedure would double your error if I'm not mistaken.

Believe the crosshairs should be put on the bullseye after group is shot and then, while holding rifle steady, adjust crosshairs to point at the center of the target. This should put center of your next group on target.

Regards,
hps

Mal H
June 1, 2003, 08:24 PM
I believe you're right hps, I got it backwards. Starting on the bullseye and moving the crosshairs to the center of the group will put the scope on the same spot as the bullets are going.

Thanks for catching that.

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