Hi guys. My buddy and I are not young anymore, not even middle-aged if you know where I am going! My friend has a 638 titanium that he had sent away to get a larger front sight installed. He can see the front sight now but the gun shoots low no matter what we do. Is it possible for me to file down the rear sight channel a bit, then polish it like I would do to SS? Looks like the smith had a heck of a time installing the front sight so there is nothing there I can adjust or modify.

Thank you, Dave

Need more info. Pics would help a lot. How much too low, at what distance? Is the front sight black, fiber optic, painted or what?
Filing down the frame seems like a bad idea. The frame is probably stainless with only the cylinder being titanium.

Making the rear channel deeper will allow you to see more of the front post only. It won't change your proper sight picture because the top of the rear will still be lined up with the top of the front and shoot low because of the taller (if that is what you meant by "larger") front sight.
To get proper point of aim, the rear edges have to be built up at the same amount (or so) as the front was.

If the gun is shooting low it's an indication that one of two factors are in play.

The first factor is "pushing off", or more exactly a Push Flinch in anticipation to the gun firing. Not the least bit surprising with a revolver as light as the 340 PD, loaded with full power 357 Magnums they are considered to have a more violent recoil than a 500 Magnum. Easy way to test for this is put one snap cap in the cylinder with live rounds in the other chambers, close your eyes, spin the cylinder and close it. As soon as you hit that snap cap you'll get a very clear demonstration on how much flinching is going on.

BTW, don't be surprised if you do find a flinch issue, I personally wouldn't ever consider shooting one of these featherweights with a full power Magnums unless there were several Hundred dollar bills laid out on the bench for me to pick up after just one shot. Because I know my limitations and I also know all about flinching after spending over 40 years coping with a tendency to flinch.

If you are a candidate to be a Navy Seal and don't have any flinch the second factor is the height of the FRONT sight. If you need to raise the Point of Impact what you have to do is file DOWN the front sight. However note that IMO you most likely cause for your shooting low is a Flinch and correcting that would be the first item to address.

PS; I know you said it was a friends problem. Perhaps quite true but it is easier for me to reply as if we were two people talking to each other. If this is really concerning a friend then hide the snap cap for him then step back and see how badly he is flinching. BTW, back when I first qualified for my concealed permit there was a 70 year old lawyer in the next lane doing his re-qualifications using a 340 PD and he was flinching so badly his shots were hitting the range floor about 8 feet in front of the range bench. It was scary enough to watch every time he stepped forward those closest to him stepped back to the rear wall fo the range.

I would suggest that your friend try a heavier bullet and load first before he attacks the gun with a file. My 642 hits point of aim only with 158gr +P LSWCHP. The faster 110, 125, and 135gr bullets all hit below point of aim.

Like scooter123 points out the problem could be shooter induced. Have someone else try the gun first before making alterations. When I was searching for a carry gun the gun store commandos kept trying to sell me a titanium 340PD. When I pointed out that might have to shoot a second time they looked at me like I was some sort of idiot. The extra weight of the 642 at least makes the revolver somewhat tolerable.

If you are having problems seeing the front sight widening the frame groove may help. Just remember that it is much easier to remove metal that it is to replace it and you have to widen it on both sides or POA and POI will not coincide.

A shooter showed me his fixed-sight gun that he paid to have installed a great blob of an orange front sight, and now his gun shoots low when he aims the conventional way. I told him he has 2 choices: file down the top of the front sight, or put the whole front sight on the target. (Which nearly covers the target beyond spitting distance)
Filing down the REAR sight will only make it shoot LOWER.


Sounds the same as the OP.

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Science plus Art

It's amazing what passes for "gunsmithing" these days. Putting a big, tall hi visibility front sight on a fixed sight gun is going to cause it to shoot low. Taking a file to the frame is only going to make it shoot worse. And it's probably going to void the warranty.

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Join the NRA today

As OKFCO5 stated. To make the gun shoot HIGHER the front sight needs to go down or the rear sigh UP.

Messing with the dovetail in the back sight is NOT a good idea . You permanently alter the gun and if you are not a machinist you can not do it properly,

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Still Running Against the Wind

Thanks everyone! This is a case of two old men conversing in error. My friend said the gun shoots high. That's why I thought the rear of the gun needs lowered. But after re-reading his posts, he said he has to aim high at the neck to hit the chest. I guess he meant the gun shoots low to POA. So yes, unless he has someone, not me, add an adjustible rear sight to raise the sight picture, he'll need to get another front sight or just keep aiming high! I certainly appreciate the time everyone gave us in their answers! You are very kind. He is planning on this gun being his final CCW, so if filing down the rear ramp a bit would have been do-able, I would have done it for him. It seems, as "retiredbadge" mentioned, my buddy put a larger front sight on to see it easier. Unfortunately, it is high enough to change his POA. I will see if he will allow me to shoot it in case we see a difference, but with a high front sight, probably not. He is set on using the GD 135gr. light frame ammo, so changing ammo is not an option. You know how hard it is to get us old guys to "change" anything once we put our minds to it! hahaha Thanks again!!!!!!!!!
Dave

Take off that front sight. Re-instal the original front sight and paint it a "bright" florescent green/red/whatever color the owner can easily see, and you should be back to point of aim.

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H Richard
SWCA1967 SWHF244

Another option is to use a different sight picture. For example, if the front sight is a big dot, then instead of holding the top of the dot even with the top of the rear sight, you can hold the center of the dot at the top of the rear sight. You can even hold the bottom of the dot even with the top of the rear sight. These sight pictures raise the front sight in relation to the rear sight, so the gun should no longer shoot low. This may sound similar to holding the front sight so that it covers the target, but the picture I am describing is different and should not require holding high or covering the target.

I have used one gun where this sight picture was quite effective for combat distances, but there are also some potential disadvantages. This sight picture will not deliver great precision, but it can be effective for paper plate sized targets out to 10 or 15 yards which is my standard for defensive shooting. It is also a disadvantage to use different sight pictures for different guns. Using different sight pictures could potentially lead to confusion under very inopportune circumstances. However, training can alleviate this issue. Lastly, the shape and coloration of the front sight can determine whether this method is really usable. So overall, this is not a cure all, but it may be another option to try out.

Thank you Jake, I'll pass it on!

If your friend is set on having the taller front sight, there is a taller rear sight available that comes standard on some S & W J frames but requires a dovetail cut in the top strap:

Performance Center(R) Pro Series(R) Model 640 | Smith & Wesson

Whether it is tall enough for the front sight in question may be answered by the factory if they are willing to do the work, or by an experienced gunsmith.

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Alan
SWCA LM 2023, SWHF 220