Smith & Wesson Sights . . .

[DrDoctor]

I recently purchased a Sightmark laser bore sight to see if my Smith & Wesson revolvers (a 460V Magnum, and a 4” 686 L-Frame .357 Magnum) from Midway USA. As an aside – I’m not a big online purchaser, but this went as well as anyone could want. In fact, they quoted me a 3-4 week delivery, but I received it in just over 2 weeks!!! On a 10-point satisfaction scale, I’d give this company a solid 12!!!
OK, on to the laser bore sight. I purchased the .38/.357 version. There’s no switch – you have to put a couple of small batteries (provided) into the laser, and then you’re good to proceed. I put it into a chamber of the 686’s cylinder, and the sights of the gun were right on top of the laser spot (exactly 25’ away). Then, I put the laser into a plastic sleeve so it would be positioned in the center of a chamber of the 460V’s cylinder, and it was WAY off. I tried to raise the rear sight, but ran out of adjustment, and I was only about ⅓ of the way home. So, I had to “chop/channel/section/and lower” (just like I did with a custom car I had for over 42 years . . .) the sight to get it zeroed in. In the process, I converted the original red-ramp sight to a brass-bead sight by reversing the sight (I reversed the original red-ramp sight on the 686, modified it (but not as severely as I had to for the 460V) to accommodate the new brass bead). Now, the 460V’s sights are right on the laser spot, too.
I do have a question resultant to this, tho’ – has anybody else encountered a situation where a revolver (in general), a Smith & Wesson revolver (in particular), or a Smith & Wesson 460V (specifically), were soooooo off with factory sights right out of the box? Thanks in advance to those who choose to respond.

[Malamute]

Bore sighting a revolver would be difficult, as the gun moves with recoil before the bullet exits the barrel. Looking at many revolvers, slower velocity being more pronounced, as is heavier bullets, longer barrels, 44 spl and 45 Colt being pretty noticeable, the bore points lower than the sights, but the bore moves upwards when fired bringing the shot in line with the sights. I wouldnt modify any part of the gun until shooting it with ammo you plan to use to confirm whatever the laser bore sighter indicates.

S&W also has different height rear sight blades for various requirements.

[john c]

I’ve never had a problem running out of sight adjustment on a Smith revolver, and I have a reasonable sample size. If I were in your shoes, I would have gotten it as close as possible with the existing sights, then shot it to see how close I was before removing any metal. There are a lot of factors of accuracy in a revolver, since the barrel is fixed and the chambers move.

With respect to elevation, bullet speed and weight can have a big effect on poa/poi differences. Bloke on the range did a video on revolver sight (mis)alignment, and why fixed sight revolvers appear to be so low, but aren’t. The same logic applies to adjustable sights.

Basically, due to the lever effect of recoil in revolvers, with high bore axis, the bore will be offset from the sights, but properly adjusted, the bullets will impact on the right spot.


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[sparkyv]

Never have boresighted anything but a bolt gun. Never had the need to boresight any handgun as it's so easy to start at a sort range, say 15' to get on paper, adjust, move to a longer distance, repeat until satisfied. Should have plenty of adjustment on those S&W sights OOB.

[Michpatriot]

I mostly adjust my point of impact with different loads, factory loads differ greatly from one weight to another and not just up and down either, sometimes trying a bunch of different rounds will get you there.. I find a weight I like and speed I can handle and then and only then mess with sights. Don't expect revolvers to print the same with all weights and you'll have a lot less stress. I have just one speed and weight for my carry revolver..it hits where I aim with that round alone, no other...good thing I can roll my own or I'd need some crazy sight work on that fixed rear sight. Report back on that sight mod on the 460 be interesting to see if the laser bore sighting got you there with no shooting the sights in..

[Jim Watson]

I would not have started cutting on the gun based on a boresighter, especially a revolver.
Live fire is best.

[willie]

Recoil and velocity interact to determine impact point in relation to sight setting. For example, in the same .38 Spl revolver, a 200 grain bullet will have a higher poi than a 110 grain bullet, which travels faster and leaves the barrel before the slower 200 grain bullet would. The barrel has raised upward less with the faster bullet. Also, the 200 grain bullet round will have greater recoil which lifts the end of barrel even more rapidly. I used these extreme weights as an example. I have a J frame that shoots too high with 158 grain bullets but has correct poi with +P 110 grain bullets.

[Wayne Dobbs]

I recently purchased a Sightmark laser bore sight to see if my Smith & Wesson revolvers (a 460V Magnum, and a 4” 686 L-Frame .357 Magnum) from Midway USA. As an aside – I’m not a big online purchaser, but this went as well as anyone could want. In fact, they quoted me a 3-4 week delivery, but I received it in just over 2 weeks!!! On a 10-point satisfaction scale, I’d give this company a solid 12!!!
OK, on to the laser bore sight. I purchased the .38/.357 version. There’s no switch – you have to put a couple of small batteries (provided) into the laser, and then you’re good to proceed. I put it into a chamber of the 686’s cylinder, and the sights of the gun were right on top of the laser spot (exactly 25’ away). Then, I put the laser into a plastic sleeve so it would be positioned in the center of a chamber of the 460V’s cylinder, and it was WAY off. I tried to raise the rear sight, but ran out of adjustment, and I was only about ⅓ of the way home. So, I had to “chop/channel/section/and lower” (just like I did with a custom car I had for over 42 years . . .) the sight to get it zeroed in. In the process, I converted the original red-ramp sight to a brass-bead sight by reversing the sight (I reversed the original red-ramp sight on the 686, modified it (but not as severely as I had to for the 460V) to accommodate the new brass bead). Now, the 460V’s sights are right on the laser spot, too.
I do have a question resultant to this, tho’ – has anybody else encountered a situation where a revolver (in general), a Smith & Wesson revolver (in particular), or a Smith & Wesson 460V (specifically), were soooooo off with factory sights right out of the box? Thanks in advance to those who choose to respond.

Good possibility you've damaged that gun to the point of requiring factory repair (or replacement). The sights are zeroed at the factory fairly close and don't usually require too much adjustment. I've never encountered a Smith adjustable sight revolver that didn't have enough range of adjustment.

[okie john]

Like most American firearms makers, Smith & Wesson has been doing a pretty good job of regulating sights since the 19th century. I've been messing with their adjustable-sight revolvers for decades and never saw one that wasn't very close to POI right out of the box with anything remotely resembling a factory load.

So, I had to “chop/channel/section/and lower” (just like I did with a custom car I had for over 42 years . . .) the sight to get it zeroed in.

Bore sighters do not zero a weapon. They can help get a scoped rifle on paper at 25 yards but they have little use beyond that because they can’t account for all of the variables: the load you choose, how your body interacts with the weapon, the scope or mounts you use, etc. In the case of the 460V, they don’t account for how the muzzle brake changes recoil characteristics, which affects the bullet’s flight as others have noted. Bore sighters are also nowhere near as precise as a well-made firearm, especially when you add a plastic adapter sleeve.

A zero gets POI and POA to coincide at useful working distances for the weapon in question. You have to confirm it on a different day, then you have to verify it with a lot of shooting at the types of distances that make sense for that weapon. Once you've done all of that, then you've got a zero.

Did you fire either of these revolvers before you did any of this? What exactly did you do? And what will it take to undo that?


Okie John