Bore Sighting

[Maverick]

Now that I have my 6.5 completed, I bought a scope and now I need to know what do you think is the best way to sight it in. I have reviewed a few laser boresighters, and they all have good and bad reviews.
Can you tell me what you guys have used and if it was worth it, or should I just go to the range and dump some ammo and get it dialed in. Would prefer to only take a few shots to get it right, but if I can get it zerod on paper first, that would be my preference.
Appreciate it, and you guys have a great weekend!!

[VASCAR2]

I have just as good luck shooting at 20-25 yards and getting the rifle on paper. I check a ballistic app for the impact at 50 yards and get the scoped at a close zero at 50. I then move out to 100 yards or whatever distance will be normal zero and get the final adjustments.

I usually start shooting at a large clean piece of cardboard at close range so I can easily find my hits and track my adjustments. Remember at close range it's going to take a lot of clicks to move the bullet impact on target. 1/4" clicks times 4 at 25 yards or 16 clicks for 1" movement at 25 yards.

A Factory 123 grain A-Max usually chronograph at 2425-2450 FPS out of a 16" barrel, 18" barrels are about 2475 and about 2500-2525 FPS for a 20" 6.5 Grendel. Using a BC of .510 G-1 @ 2475 FPS with the center of the scope 2.7" above the center of the bore yields impacts 1.5" inches low at 25 yards, at 50 yards .6" low and zeroed at 100 yards.

[rabiddawg]

I usually just shoot at 25 then move to 100.

1" low at 25 and I'm close at 100 usually

Don't be high at 25 or you will be way hi at 100

[mongoosesnipe]

i don't bother with bore sighting i just mount the scope square and straight and shoot it a 25 yards depending on what I'm shooting or my goals i will usually just zero at 25 it usually lines up to zero between 200 and 300 hundred and a few inches high at 100

[A5BLASTER]

What I do with my bolt action rifles is sight it a half inch high at 25 and then shoot at a 100 and dial it in.

Seems to me it should work just as good with the ar, I didnt do it that way with my grendel, the range I use is owned by a gunsmith and he uses a laser sight to bore sight at 100 and then shoots 3 rounds to get it close.

Problem with that is when I got on the gun and shoot it was way off, Im a firm belever never let someone sight your rifle for you, reason being in my mind is they wont hold or shoot the same as you and it will throw the point of aim off from how you will shoot and your natrul point of aim and sight picture.

Hope this helps sir.

[JASmith]

I would add that THREE shots is never enough to sight in a rifle unless one already knows the typical group size from that rifle.

Even 5-shot groups will have enough differences in their centers to make one think he is off by a fair fraction of an inch for MOA-class rifles.

So, do the rough sight in, then shoot a series of 5-shot groups over several range days with the settings used for the rough sight in. Then make an adjustment based on the aggregate group center.

There is a discussion on the Zero for Hunting page that offers an approach to formalizing one's sight in so it is more stable over time.

[AZ. Old Guy]

Take the upper off and set on a table or something stable. Sight down the bore at an object like a rock. Carefully look up through the scope and see if the cross hairs are on the object. Adjust as needed remember that to go left turn to the right. Works well for me. My "object" the hubcap on the car down the block����

[rabiddawg]

A5, keep in mind the scope on your AR is higher than the one on a bolty. If you go an inch high at 25 with an ar you may shoot over a sheet of notebook paper at 100 and farther

[lrgrendel]

Take the upper off and set on a table or something stable. Sight down the bore at an object like a rock. Carefully look up through the scope and see if the cross hairs are on the object. Adjust as needed remember that to go left turn to the right. Works well for me. My "object" the hubcap on the car down the block����

I agree with AZ OLD GUY.

Also don't take the upper off. Just take the BCG out and leave the forward pin connected. If you have a bipod put it on and follow the above instructions.

Works every time....

[Klem]

I look through the barrel at something identifiable at 100. Then slave the sight to the object. Then fire a few shots at 25 and adjusting the sight after each shot so the POI moves to where it should be according to ballistic tables. Then fire at 100 to fine tune.

Forget laser boresighters. Only useful if you are in a place where you can't fire rounds and you are issued kit that needs zeroing. Even then it's never as precise as firing live rounds.

[rwh]

I also just look through the barrel by taking out the carrier and leaving the front pin in. It gets me on paper every time.

[kmon]

Klem and AZ Old Guy are right on track. Carefully done it can get your real close to being on.

[PredatorDown]

If you have a decent sized berm at 100 yards I see no need to start at 25 or 50 yards. I'll set something like a water bottle or clay pigeon out on the berm and fire the first shot. It's easy to see the dust from the impact in relation to the bottle/pigeon, and will adjust accordingly. Unless it's several feet off, I can usually connect on the second or third try. Once I hit that, I'll move to paper target to finalize.

I took my new 7SAUM out to sight in today. Spent the morning shooting prairie dogs with the 5.56, then decided to shoot a couple of rounds through the SAUM to get close. Keep in mind I just pulled my NF off the Grendel and had it in a 50MOA mount, so I knew I'd be way off. Dialed down about 30MOA (it's on a 20MOA rail now), and within 3 shots was damn near hitting the prairie dogs at 100 yards. Since they're not a static target it was hard to get a good zero. I stopped after 5 rounds. Then a few hours later I went to the range. Put my first shot on paper, measured with the reticle and put my next 5 about 1/2" above the bullseye.

All said and done, I was pretty well dialed after 7 rounds through a brand new rifle/barrel. The first 5 of which were at targets that wouldn't hold still after I shot �� And switching from an extreme canted MOA change. Maybe I'm the odd one out, but using this technique I can usually be on paper in 3-4 shots and dialed in with a total of 6-10

[VASCAR2]

If you have a decent sized berm at 100 yards I see no need to start at 25 or 50 yards. I'll set something like a water bottle or clay pigeon out on the berm and fire the first shot. It's easy to see the dust from the impact in relation to the bottle/pigeon, and will adjust accordingly. Unless it's several feet off, I can usually connect on the second or third try. Once I hit that, I'll move to paper target to finalize.

I took my new 7SAUM out to sight in today. Spent the morning shooting prairie dogs with the 5.56, then decided to shoot a couple of rounds through the SAUM to get close. Keep in mind I just pulled my NF off the Grendel and had it in a 50MOA mount, so I knew I'd be way off. Dialed down about 30MOA (it's on a 20MOA rail now), and within 3 shots was damn near hitting the prairie dogs at 100 yards. Since they're not a static target it was hard to get a good zero. I stopped after 5 rounds. Then a few hours later I went to the range. Put my first shot on paper, measured with the reticle and put my next 5 about 1/2" above the bullseye.

All said and done, I was pretty well dialed after 7 rounds through a brand new rifle/barrel. The first 5 of which were at targets that wouldn't hold still after I shot �� And switching from an extreme canted MOA change. Maybe I'm the odd one out, but using this technique I can usually be on paper in 3-4 shots and dialed in with a total of 6-10

As wet as it's been in my neighboorhood this summer your lucky to see bare ground anywhere around me. With the heat and humidity the grass and weeds have just about covered everything, including my chat driveway. I could stand a few days of low 60% humidity let a lone your 20% humidity out west.

[lwminton]

I also just look through the barrel by taking out the carrier and leaving the front pin in. It gets me on paper every time.

Could you explain this in more detail. I am not sure what "pin" you are speaking about. By "carrier", do you mean the entire bolt?