CenterPoint Laser Boresighter, .177 to .50 Cal

Pros
Cheap

Cons
As noted, it does not fit .177 barrels snug. Rotate iit in the barrel and the dot is all over the place. Went back to using paper targets with better results.

Before pulling the trigger on this one I looked at reviews, not only
on this site but others. I believe you get what you pay for and at $30
I didn't expect much and I got what I was expecting. It got me on the
paper, that saved me lots of time and money and for this I give a rating
of 5. Small caliber (.177, .22) sighting devices are hard to find and
this one was extremely helpful in sighting my 3, .177 caliber air
rifles.

Pros
It's a Lasor.

Cons
The stem is not suited (long enough) for shrouded air rifle barrels even though I found compromises. Windage was good just had to adjust elevation.

Very nice that you can use one boresight for all muzzle sizes.

Pros
Worked great on my 50 cal guns.

Cons
none

The only problem I had with it was the batteries for the laser were corroded and didn't work. but I had backups once I installed them put it in the gun align my sights. took it out of my barrel, shot down range. I couldn't ask for a better laser pointer.

Pros
It worked great.

Cons
Put better batteries in the box.

I'm sure that it will do its job in any non-shrouded, non suppressed gun, as well as many shrouded ones, as it's adjustable with a hex key on two set screws (though I don't recall seeing any adjusting key included). The bore plugs screw on, so shouldn't get stuck in the barrel.

I bought this to sight in a Benjamin Mayhem .22, with SBD. It's stem is too short to reach the barrel, and I've yet to find an extension to fit the M3 × 0.5mm threading. I presume I'll have to either buy a 3 × 0.5mm tap and die set or cut this stem and epoxy an extension in the middle. It's even a bit short for some shrouded barrels.

The switch appears that all you'd have to do is rotate the plastic battery holder off of center to turn it off, but the spring is too strong for that. So, you need to push the battery holder toward the front (laser-side) of the sight then rotate it either direction to turn the laser off. A bit of a pain.

I might just try to rig up a string, instead.

Update: I've found a very simple workaround for the short stem in smaller, integrally suppressed barrels (.22, .25, perhaps .30. Larger bores might be harder to fix this way): take a plastic drinking straw that's long enough to cover the baffles and reach the barrel, and cut a slit from one end to the other. It becomes a thin springy conduit that can be placed inside the opening of the barrel, and cover the baffles with a cylinder quite close to the size and orientation of the barrel.

Note: Try to keep the straw sticking out of the muzzle a small amount, spreading the split straw around the cone of the boresight, as shown in the attached picture, otherwise the straw can be slightly difficult to remove. (Using a cleaning tool/patch puller works to remove a stuck straw)

Pros
Adjustable Fits more standard barrels than many competitors, who are limited to .22 - .50 cal The bore plugs screw on Nearly all the photons emitted are parallel to each other.

Cons
Too short for some shrouded and most, if not all integrally suppressed airguns Power switch is too 'fiddly'

This is a nice idea but if you have an air gun with noise suppression it does not have a prob long enough to reach the actual barrel. This is a problem because you can't stability the laser. Works fine for airguns with out suppression.

Pros
It worked with non suppression airguns

Cons
Did not work for suppressor equipped with it.

...bought this laser Boresighter for my old faithful air pistol....works perfect out of the box...put the shots right where they should be...highly recommend this sighter for anyone that wants a closer shot...CEH

Cons
none

Used this on couple of guns 1st one was close enough to hit near bull did not readjust scope and was hitting 2 inch group I think this was due to me or the pell was Crosman recruit pump no riffle in barrel

Pros
Gets u in the zone

Cons
Some trouble with certain barrels loose fit

I got this for my. 177 with some doubt .
My break barrel really goes thru scopes and getting sited in is getting old . This is my first barrel sight and can't imagin going back to being without it . Ha
As a test I put the sighter in noted the laser location in the scope , pulled out the sighter and fired using the location noted with sighter ,bam every time I tried this I hit the target dead on . Although my scope would shift every time .

Pros
Time ,ammo saver Works awesome , Multi usable .

Cons
Could use better on off switch .

The insert for .177 caliber is too small and because of that boresighter sits too loose in the barrel.

Cons
.177 insert diameter is not big enough to sit tightly in the barrel.