Laser Boresighter

minktrapper

Anybody got a Bushnell laser boresighter.Is it any good for checking scope zero before shooting.Or is it only a gimmec.

Cass

Laser Boresighters are not a tool designed to get you on the bull from the off, but a tool to get you onto paper.

The laser is a "line of sight" device. Meaning it shines a light in a straight line. No bullet travels like that so it can never zero the rifle for you. What it can do is help you see where the bore of the barrel is pointing, to a certain degree of accuracy, and then you can asdjust the scope to match the laser's dot. Once on paper you can fine tune the POI by adjusting after each shot.

For the price it's not bad, but unless you are zeroing on a regular basis a look down the bore will do the same job for free. The most any zeroing of a rifle shoudl take is 3 shots.

pioboyle

Hi i have a busnell laser boresight and i found it useless the old fashioned way i found best..

Constab2

Try the Site lite 150 excellent piece of kit

Cass

Here is a post i wrote a while ago. Covers the basics, and works a treat.

Ezridax wrote: »

No. Personally i would start at 50 yds. Go back to basics. Open rings and remove scope. Check ring bases are securely fixed to rifle/rail.Place scope back into ring bases. Check for eye relief. Place the top piece of the rings back on and loosely screw down. Do not tighten yet. Once again check your eye relief. Use either sprit levels or the piece of string method to line up the crosshairs on your scope (or whatever works for you). Without moving the scope tighten down all screws. Now your scope is back on and ready to be sighted in.

Turn the clicks on the scope (elevation) down to the lowest setting. Now turn the clicks on your windage adjustment all the way left (or right). Now turn it in the other direction while keeping count of the mintes/clicks. If its (for talks sake) 50 moa turn it back 25. Now your windage is centralised. Place the rifle in a clamp and check its level. When you peer down the barrel make sure the circle made by the muzzle is central in the circle made by the breach.



Move the rifle (not your head) until the target (at least 2ft x 1.5ft with concentric circles)



can be seen . Now keep the target in view through the barrel while trying to keep both "circles" central. Once you think you have the target in the barrel and all aspects centralised and secured, reclamp the rifle again making sure nothing moves. Now look through the scope and see where your crosshairs are in relation to the target. Turn up your elevation turret until you are approx. level with where you have sighted the barrel. Go between the barrel sight and scope and try to narrow down the difference in "point of impact". Adjust elevation and windage as appropriate.

Bolt in and load a round. Steady yourself and fire. Check your point of impact. Adjust your scope the necessary clicks to compesate for wind drift and high or low impact. Your scope is probably .25" click value at 100yds so don't forget you'll have half that movement at 50yds. So if you are 2" out it will take 16 clicks to move the 2" rather than the 8 clicks at 100yds. Don't forget that this is scope movement, as in straight line of sight. The trajectory of the bullet being used will determine whether the full amount of clicks is needed or if more are. Anyway load a second round after adjusting the scope and fire. You should be very close if not in the bull. Adjust scope again if necessary. Load and fire a third round. this one should be in the bull (weather and shooter permitting).

Make note of the turret markings and record them as your 50 yd zero. Now move to 100yds. Fresh target. Without adjusting the scope fire at the 100yd target. Take note of the bullet drop and adjust your scope accordingly to compensate. Fire another 2 or 3 rounds to establish a group. When you are happy with your group, record the turret markings and if possible zero the turrets and keep as your 100 yd zero. You can then move to 200 and 300 if you want. Fire and adjust the scope. Record the bullet drop and click value to compensate ans voila you have your drop chart started.

Of course you could always go for a bore sighter/ laser guide and cut out half the crap i just wrote. Whatever works for you. If you find when firing at the 50 or 100yd targets that the rifle cannot keep a group or still will not hit paper then i'm afraid it may be a bit more serious than just needing to be rezeroed. At all stages keep checking screws and making sure all items are tight.

Hope this is of some help.

minktrapper

Thanks for replys.Is that a birds nest at the of the rifle barrel.

Cass

Haven't a bull's notion. It was a random picture i found that had a good clear "down the barrel" picture.

4200fps

Them lazers aren't great. You still will have to adjust after its lined up. I wasn't impressed. Do it the normal way

rabbit assassin

As Ezridax says they are just to get you on paper. Dont waste your money. Ive one sitting in the press the past few years. A friend gave it to me for nothing before he emigrated so luckily I didnt have to shell out any money for it. All it does is save you the price of 3 or 4 bullets when zeroing which when you think about it, it isnt any advantage really !

minktrapper

If you put the laser in where the bolt goes would it not put youin an exact straight line to target.

Cass

minktrapper wrote: »

If you put the laser in where the bolt goes would it not put youin an exact straight line to target.

Doesn't matter where the laser is placed or shines from. As said above;

Ezridax wrote: »

The laser is a "line of sight" device. Meaning it shines a light in a straight line. No bullet travels like that so it can never zero the rifle for you.

By this i mean the laser will go from the chamber/muzzle in a dead straight line, and not be effected by wind, light, rain, sun, etc. A bullet travels in an arc from the time it leaves the muzzle to the time it impacts the target.

If you had a scope on a target at 100 yards, and shined a laser down the bore i guarantee neither will be pointed in the same direction*. What you are doing, if you can follow, is aiming at a point and knowing exactly what effect gravity, wind, etc will have on the bullet, and predicting where the bullet will "land".

For example. In a 10 mph wind, left - right, at say 600 yards (i know it's not zeroing, but the principle is the same) you need to bring your rifle up by 15 MOA (60 clicks), and aim 5MOA (20 clicks left). Now your scope is still pointing at the bullseye on the target,. But the rifle barrel is in fact aiming approx 8 feet over the target, and 3 feet left of it. You are now approximating that the wind will "blow" the bullet back right, and gravity will pull the bullet down so it impacts the bull at 600 yards.

Now after the shot place a laser in the chamber/muzzle. It will shine straight and true, and be shinging 8 feet high, and 3 feet left. Hope that translates from my head to screen.:D

minktrapper

Would it not still give you a point of reference to work off of.

Cass

Thats what it will do. Get you on paper. Not zero.

However for all the times you may need one, do you need one? They are not expensive so if you wanted one go for it. Personally i throw an eye down the bore, and it does the same job.

minktrapper

What i am trying to say is if you pass a light through a barrell it will travel in a straight line.If you look through a scope what you see on the cross hairs is on a straight line with your eye.So if you zero your scope at a certain distance there should no need to ever fire a bullet again to check your zero.Correct me if you think i'm wrong.

Cass

I may not be fully understanding you so all i can do is say what i've said above. The line of sight through a bore/barrel, and the line of sight through a scope do not point at the same spot. They would "intersect" at some point as the bullet passes through the scope line of sight, and once more as it strikes the target at the POA.

However due to the arc the bullet travels in a bore/barrel and scope line of straight/direct sight are not the same.

minktrapper

If you pass a light through a barrell and mark the spot on a target at 50 yds now fire a bullet through it at the same target and it impacts the target for example 2" high and 1" to the right of where the light beam hit it .Will the bullet now and forever more hit the target in the same place.So now we can ajust our scope to our point of aim.

Vegeta

The Hawke Shot saver is designed to do what minktrapper is talking about I think.

Cass

Now i get ya.

Not really. It depends on the position of the laser in the bore, the "true-ness" of the guide rod of the laser, the scope being the same/mounted in the same position, and of course the ammo being the same consistency/brand/batch.

If all these factors remained constant then technically yes. You should be able to re-zero using this process. However trying to do so without firing at least one shot to confirm would be risky.

ormondprop

Bought a bushnell one years ago and binned it, absolutely useless, the little arbors that stick into the barrel were cheap plastic so wern't even centred properly, put it in 1 way and look through the scope you'd see the red dot about half a foot to the side, pull it out and put it in again and it would be pointing somewhere completely different, save your money for ammo,

minktrapper

Thats why I said if you passed a beam of light through the length of the barrell and everything else being the same I think it would work.So someone more tecknechally minded might come up with something.One for the Dragons Den.

Cass

Problem is it doesn't work that way, at least not with the brands available to us so it's kinda moot.

There is a way to make it work. Put more time, and R&D into precision fitting guide rod/inserts for specific calibers instead of generic ones. However when you take into account all the precision making it would require to make sure they were 100% better or 90% more accurate the cost could go up by 100, 200, 300%. If not more.

minktrapper

No guide rods needed.Just really bright light.

Cass

You need guide rods.

If you are thinking of putting a light into the breach/chamber and shining an intense light then its a waste of time as the light will spread in all directions once it leaves the bore/barrel.

If you intend to use a laser then it need some sort of guidance aid to make sure it is securely situated in the centre line of the barrel.

minktrapper

I'll trust you on that one.

Cass

Without contradicting everything i'e said thus far, you can make up your own mind. I'm only going on basics having never owned one. Used one, once or twice, but never seen the need to own/have one.

ormondprop

They make calibre specific ones in the shape of the cartridge but they are expensive so contradicts the reason of buying one in the first place in my opinion when all they really do is save a couple of shots when mounting a scope, and checking zero only ever really need 2-3 shots either, for the cost involved you'd be better off putting the extra bit towards a better scope or mounts that shouldn't lose zero or extra ammo

ormondprop

http://www.scottcountry.co.uk/products_detail.asp?productID=1649
Heres a link to them, pricey buggers but probably a lot better than the bushnell one i had but unless i ever buy an unusual calibre rifle that is expensive to feed i don't ever see myself buying one

minktrapper

Very good,worth watching.

clivej

Here something else to look at. It will get you on paper and works on all barrels.

Zero Point Magnetic Illuminated Boresighter.

This revolutionary boresighter will get you on the paper – and much more – faster than ever. Its unique lens aperture system eliminates point of aim errors resulting from parallax due to extreme misalignment. The boresighter also includes natural backlighting of the target, LED illumination for use in low-light settings, and an inch scale for measuring approximate riflescope height and target group sizes. Check your zero. Set new ranges. Compatible with any caliber firearm. Energy efficient design yields 25 hours of battery life. Range cards for recording sight-in information are included.