Bore sighting your own gun... Do any of you do it ?

[jsparks747]

I use it at 50 yards for all my rifles and then move out to 100 yards and shoot it in the rest of the way. Get one that is either magnetic or is chambered like a round. The ones that are just poked in the end of the muzzle wiggle too much.

 

[Switchblade666]

Ok thats what I was thinking. I saw some video where the guy laser boresighted his scope @ 25 yards by matching crosshairs exactly to the laser dot, then at least got on paper with that technique @ 100. Just wasn't clicking in my 1 cup of coffee brain at 5 this morning how that would work ballistically. Yea this is an old bubblegum thread..

 

[mjbskwim]

I'm not sure why anyone would have someone else mount a scope for them. I mean it's about 14 screws!
And I don't use a bore sight I just look thru the barrel and the scope at a object about 100 yds away. That always gets me on paper. As close as the 2 times I had someone use a bore sight on my rifles.
And a gunsmith showed me how to use a mirror on a semi auto and a lever gun

 

[bbbass]

I'm a big fan of the cartridge lasers for semi-autos. Friends that used the free service at various places were never on paper and we had to start all over.

Yes, the big cardboard is the real deal!

 

[bbbass]

After bore sighting, I use ballistic tables to predict where I want bullet impact if I then sight 2" or 3" high at 100yds. That's because I'm too lazy to walk to the end of our 300yd range.

IMO knowing your Point Blank Range is an excellent concept.

 

[mjbskwim]

Hey we have a drive next to our range
Walk to the 300 yards end

 

[2A2Dend]

I like those magnetic ones for the end of the barrel.If you spin it and the dot stays true, it's a pretty accurate one. I put the cross hairs just over the dot at around 30 yrds and that will usually get me on a 10" target at 50 when sighting the gun in.

I'd like to look into what you mention. Is there a link?

 

[Koda]

I honestly dont know why bore-sighting is such a problem or need to invest money into a tool. Even on weapons where you cannot sight thru the bore, you just start out closer to get on paper. Every time I have had a store bore-sight a new scope, it never was on paper, not even close.
dont waste your time or money, just align down the barrel or start out super close for the first couple shots.

 

[Switchblade666]

I'd like to look into what you mention. Is there a link?

ShootersCalculator.com | Point Blank Range Calculator

 

[edslhead]

I'd like to look into what you mention. Is there a link?

No links, this is just the way I do it. I put the gun in my rest and spin the magnet laser. If the dot doesn't rotate in a circle on the wall I assume its fairly accurate. Homemade chili in the background is optional, but helps.

Then I just line up the cross hairs outside on a fence or something.

 

[edslhead]

I honestly dont know why bore-sighting is such a problem or need to invest money into a tool. Even on weapons where you cannot sight thru the bore, you just start out closer to get on paper. Every time I have had a store bore-sight a new scope, it never was on paper, not even close.
dont waste your time or money, just align down the barrel or start out super close for the first couple shots.

It helps save ammo when your playing musical scopes

 

[Switchblade666]

I tested my Laser on my kids 10/22 and with the right bushing it stays true. Even when I rotate it. As long as the target is big, then the fine tuning will be easy!

 

[Koda]

It helps save ammo when your playing musical scopes

yes, to clarify my opinion though I'm referring to buying a bore-sight tool not the practice of bore sighting itself.

I can see how a bore-sighter tool might be useful if a person owned several rifles that cannot be viewed thru the bore axis, like a 10/22 and had different scopes they wanted to change out all the time. Not certain why one would do that though.

 

[MrMillspecer]

I honestly dont know why bore-sighting is such a problem or need to invest money into a tool. Even on weapons where you cannot sight thru the bore, you just start out closer to get on paper. Every time I have had a store bore-sight a new scope, it never was on paper, not even close.
dont waste your time or money, just align down the barrel or start out super close for the first couple shots.

I agree. Start close 15-20 yards get centered. I like to see how far things are off on the first few shots when the scope is zeroed and tight. Tells me about the setup right off. Move back fifty zero and zero at 100. Save the money for trigger time and ammo. Should be under 2" CTC at 100 yards 5 shot groups.

 

[edslhead]

yes, to clarify my opinion though I'm referring to buying a bore-sight tool not the practice of bore sighting itself.

I can see how a bore-sighter tool might be useful if a person owned several rifles that cannot be viewed thru the bore axis, like a 10/22 and had different scopes they wanted to change out all the time. Not certain why one would do that though.

I even get all my rifles out once in a while and try to decide which scope is better suited to each gun. I think I may have a scope fetish Ive got 3 scopes with no riffles yet.

 

[2A2Dend]

@edslhead Thanks for clearing my thoughts. Which, for some reason I was thinking you were spinning some type of target!

@Koda I've had a bushnell boresighter for years. It works great for my hunting rifles. I dug it out of the cabinet one day and tried it on my AR15. Too much bore offset. Then I set it up and looked down the bore and aligned the scope. It works.

Then I did a little searching relative to my Bushnell Boresighter. There (somewhere out there) is an adjustable offset adapter that will work for higher bores. I never did find one to buy, but there are images of them I found on Google. The offset adapter isn't "necessary", though if I find one for a respectable price, I will buy one.

 

[P7M13]

@mjbskwim is right on - mount it yourself. The stuff you learn doing it yourself is invaluable.

Info: There are lots of great, great sites out there that explain the geometry of a barrel/sight and the trajectory of the bullet. Leupold's instructions are also great at helping this understanding.

Advisory:

• GIGO applies here (garbage in / garbage out). If your mounts are crooked, you may get it zeroed at 100 but not know why it's so off at 200 / 300, etc.
  
• Parallax has an effect, too, and if the cross hairs aren't as close to the lens optical axis, the farther you shoot, the more parallax has an effect.
  
• The cross hairs must also be absolutely level in their mounts. The optical axis of the scope and the bore axis make an acute angle (which is why the bullet seems to rise....) If your cross hairs aren't aligned with this, it will affect your accuracy. Assuming all is aligned properly, same theory goes for holding your rifle level.

Preparation:
If your ring mounts aren't mounted, you may want to have a gunsmith mount them if you don't have the pointed dowels. Alignment on the sight mounts is critical. If you don't have them but still want to do it yourself, put your scope in the mounts without clamping it and gently tighten down the scope mounts, rotating the tightening between all the screws. To do this on some, you cannot have the scope in there. Essentially, you want to have the same level of torque/force on each screw as you move along. This is the best way to keep it all aligned naturally. To wit: how many of you have tightened something down and watch the whole assembly shift as you are at the last stage of tightening? Doing each screw a tiny bit at a time makes all the difference.

I prefer to use Picatinny rails on all my guns because I can then take the scope off and on for storage, transport, etc.
I have a machine base I use to mount scopes in rail mounts and make them perfectly level. Snap!

Info you must determine beforehand:

1. What is your sight to bore distance? i.e. cross hairs or red dot to centerline of the bore.
2. What distance do you want to zero for?
3. What are the ballistics of your most typical load? I use Gundata.org. On custom loads, I'll use my bullet BC and known MV.

How I do it sighting down the bore:

1. Remove the bolt. On an AR, this means removing the lower too.
2. Mount the gun or upper in a gun vise or some other jig to hold it securely.
   
3. Use an accurate level to level the gun in the sight plane: side to side, front to back.
4. I set up a plumb bob and a fluorescent string, typically between 15 & 25 yards. For example, at 15 yards, an Eagle 223 55gr bullet will be 1" below the 100 yard zero.
5. I look down my bore and have a bead on the string to move up and down to accurately locate where bore center is.
   
6. I then make sure my sight is pointing to 1" above that bead.
7. [edit] Years ago, I saw on Sniper's Hide a post by one member where they had a jig that had a vertical line with inches to the 16th, meter scale to the mm and a mount for the plumb bob string. He used it to sight in MIL or MOA scopes. Seemed pretty cool, but I don't have a CNC mill at my disposal....

I bought a cheap-azz POS laser bore sighter with the expandable button end, at Sportsman's on clearance, 50% off lowest marked price. I think it was $20.
For bore laser sighting, I don't remove the bolt or lower. I also don't use the string bead, since the laser makes the spot easy.
I recently did my 6.8 SPC build doing this with a red-dot. Testing it last week, POI/POA was 1" off, 45° high and left at 100 yards. I was pleased.

 

[bbbass]

Hey we have a drive next to our range
Walk to the 300 yards end

Crud, I can't see 300yds even with a 12x scope. Drive? I thought that was golf.

 

[mjbskwim]

I don't use dowels,I tighten my scope rings to the scope first. Then they also gun to it without any torque.
The last step is tightening the rings to the base(s).
I don't loctite anything but the bases to the gun
Also,you don't really need a torque wrench. Just use 2 fingers,only 2 fingers to tighten the screws. If you have strong hands and are using a screw driver with the interchangeable heads take it easy on it.
First hand knowledge. No pun intended
And like mentioned above sighting thru the bore has got me within 2 shots to POA. My 700 7mm and my vortex viper, I shot,adjusted the scope to the POI and bullseyed the next shot.
I got lucky that time,lol
There are a few other recent threads on this to read also.

 

[galvweld]

My dad, long gone, set us up at 25 yards. Taught us ammo is expensive. If we hit at that distance, not all over, but accurate three shot group he gave permission to range out to hundred.
Before shooting we mounted scopes without any special tools. Used a window sill to make sure cross hairs were level. Since we only had bolt rifles, pulled the bolt, set rifle in secure rest and peer down the action to a spot in near distance. Secured the scope after aligning the cross hairs on the same spot. Worked then and still works. Have used laser sights that you place in the bore with some decent results. Used Bushnell bore sight that has a matching caliber shaft to attach sighting instrument. Match cross hairs to grid. Not always on. Haven't splurged on caliber specific laser that is chambered in the bore. Should be excellent. As much as anything that is important is proper securing the bases to the rifle followed by careful mounting the scope into the rings. Tightening by securing across the scope, not directly across but on the other side. Have some history with scopes being defective. Ultimately the shooting of the weapon either reveals a problem or confirms the bore sighting. Some times it is the shot that is off, it is the shooter.