Final UPDATE -- 640 Pro Series - How Low Is Too Low??

[Edmo]

My 640 Pro shoots lower than point of aim...

History: This gun was shipped new to me from S&W via my local dealer. I had to send it right back to the mothership to fix several issues to include a clocked barrel.
S&W twisted the barrel straight and returned it to me. After 6-8 months of shooting, the barrel had turned and was again clocked. I sent it back to the mothership again. I don't know what they did to fix the clocked barrel the second time, but the point of impact shifted.

Originally the gun would hit pretty close to the point of aim. When it was returned the second time the gun hit low. I installed a Crimson Trace laser grip and after aligning it to the point of impact I compromised and called it good.

Today I took it out to a local outdoor range and tried several types of factory ammo in the gun. With the bright sun I couldn't rely on the laser as a crutch. The target was at 15 yards and I shot from a rest using the iron sights.

Ammo today was three different loads by Remington... 125 grain 38 +P SJHP, 125 grain 357 Mag SJHP, and 158 grain 38 +P LSWCHP.

The below pics are as follows:

First - The gun.

Second - This pic from today shows a group of five 38 SJHPs and five 357 Mag SJHPs. Both types grouped near each other. The center of the group is 6.5" lower than the aiming dot. I didn't include a pic of the 158 grain target, however it printed 6" low.

Third - This is a group of the same 38 Special +P SJHP rounds before the second barrel tweak. Although only 5 yards, it shows what the gun could do.

Question: Should this gun make a third trip back to S&W to fix this problem?

Edmo

 

[Zipdog]

Sounds like you got this one after returning another one. At some point you have to realize not everything is perfect. No not even a Rolls Royce.

 

[twodog max]

You might try heavier bullets and see if the POI comes up.

 

[gnystrom]

Don't feel alone. My 640 Pro (which went back for visible flaws in the stainless) also shoots a bit low at 30' and I compensate by imagining the front dot sits higher up in my sight picture. Sort of a triangle with the dots rather than the traditional all in a line. I am sure the front sight is too tall but at this point there are not a lot of options, so I added a set of Crimson Trace LG350 green which completely solves the problem.
I mentally defer to the fact the 640 Pro is a SD gun and absolute precision is usually not needed or expected. Oddly, I do not have this issue with any of my other S&W snubbies. All of them shoot dead on POA at 30'.

I hope I have eliminated future issues from the Performance Center by ordering and awaiting delivery of a new Kimber K6s.

 

[APS]

Are you aligning the straight edges of the sights or the dots? If using the dots, do they actually align correctly so when they are in a row, the straight edges of the sights are aligned? I have seen the dots/edges off on handguns before. Have you verified with dry-fire that the front sight isn't dipping when the trigger breaks?
If everything is OK there, I would not be happy with that 15yd performance. That would put the gun 6" low at 25yds. The whole point of decent sights on a J frame is to improve shootability.

 

[ridgewalker]

If after experimenting with different load / bullet combinations, you cannot find one that gives satisfactory results, then maybe you can try replacing the front sight with a lower front sight.

I wish S&W would just replace the revolver for you with a new one that was good.

 

[wheelyfun66]

I'd have someone else shoot it, to verify, then ship it back and send S&W the pics.

 

[andyo5]

I haven't shot the Pro, just my 642 and 340.
However, if dots are provided on the sights, that is the aiming picture that should be aligned on the target. If you place the tops of the sights on the target, that actual POA will be the dots and so you will print lower than you expected.

 

[bronco45]

I've got a 640 Pro and #1. This is a combat weapon. #2. Gun is regulated for 158 357s, which will bring your POI up. #3. In a SD situation at the usual ranges and time frames, align the white dots center mass and smoothly but quickly press the trigger, that's all the time you're going to have!

 

[diyj98]

If after experimenting with different load / bullet combinations, you cannot find one that gives satisfactory results, then maybe you can try replacing the front sight with a lower front sight.

I agree. If you're happy with the load you're shooting, just replace your front sight with a lower one.

 

[gnystrom]

The 640 Pro has a special dovetail med large dot front sight. I am unaware that there is a shorter option. The best answer is learn to mentally adjust to get the correct POA-POI.

 

[Edmo]

Some notes...

On this same outing my 642 was right on the money at the same distance with both the 125 and 158 grain 38 Special +P loads... Not 6 plus inches low.

I do dry fire quite a bit with this revolver. Having fired this and many other of my revolvers in double action with good effect, I will suggest the low impact isn't related to shooter technique. Especially when the first barrel was hitting pretty much point of aim.

Maybe I expect too much of my revolvers, especially a Pro Series gun. I guess I could just knock the sights off of the gun since I shouldn't need them, right? Combat handgun and all...

I'm on a trip out of town right now, but will be calling for a shipping label when I get home. We will see what they say.

Edmo

 

[SAWBONES]

As others said, the J-frames are designed to hit to sighted POA with 158gr+P loads, and lighter loads will typically hit lower.

When an expensive "Performance Center" gun won't naturally meet that standard, there's something wrong with S&W's quality control.

 

[J D Boyle]

Doesn't "shoot"

The gun doesn't shoot straight. A lot of people feel this in an important part of the handgun experience. Raise Hell! They don't give 'em away.

 

[roundels]

640 Pro POI

As others said, the J-frames are designed to hit to sighted POA with 158gr+P loads, and lighter loads will typically hit lower.

When an expensive "Performance Center" gun won't naturally meet that standard, there's something wrong with S&W's quality control.

Ooh-don't even get me started on modern day "QC." Not so long ago, I bought a Model 40 Classic with the Turnbull case hardening and it was rough as a cob in every direction. If Smith has gotten a rep for quality slippage (and they have), they've earned it. I'll stick with my perfectly finished 1992 mfg. dual cylinder (9)640 that will put 5 rounds of Federal .38 +P into an inch at 7 yards and 5 rounds of Cor-Bon 9mm+P through one smooth hole at the same distance. Remember when such accuracy was the general rule?

 

[Andrew2105]

I believe that this revolver is best suited for use as a self defense weapon not a target pistol. I suggest that you see where your groups are after drawing from your holster & firing with your upper arm vertical against your rib cage and forearm horizontal (about 90 degrees).
Somewhere around 5 yards or less would seem to be a practical distance. Now if you are trying to use this revolver as a target pistol, disregard my comments. If the sight can be corrected, that revolver can be fired accurately at much longer distances than most would believe. good luck with S&W.

 

[KertP]

Edmo, The 640 Pro's sights are regulated for 158gr .357. I carry it with 158 gr. Federal HydraShok, which shoot to point of aim at 15 yards. On a lark, I sent it off the Mag-na-port and had it ported. Really makes it nice with the .357 Mag rounds. I've shot it at night and the flash is out the end of the barrel, not the ports. I discovered the POA/POI impact disparity when I first shot it with Hornady Critical Defense .357, which it shot low. I then remembered that my Model 60 (no dash) always shot low with anything other than 158 gr .38 Spl, so I tried the 158 gr Federal Hydrashok .357 and, voila, POA and POI match. Try that before you send it back to Smith & Wesson.

 

[gunbugs]

You may find that how tightly you grip the gun on any given day will alter your point of impact. A tighter, or death grip will tend to shoot lower than a looser, live bird in the hand type of grip. Plus, bullet weight and velocity play a part as well.

 

[Revolver-dude]

Gonna disagree!

Sounds like you got this one after returning another one. At some point you have to realize not everything is perfect. No not even a Rolls Royce.

I can hit the target with rocks more accurately than your target. That gun would be going back immediately. You aren't asking for perfection, you are asking for a S&W to hit CLOSE to point of aim and this gun ain't doing it.

 

[allendavis58]

This is a bit unrelated, but my parents (both 80+) just purchased a matching pair of S&W 643s which are marked with the Performance Center logos rather than the standard S&W logo. I was extremely impressed that both guns had remarkably light double-action only pulls. I never thought it possible in such small revolvers. Nonetheless, Mom's gun shoots extremely high even at short range. At only 15-feet, Mom's gun shoots 18" high. I've tried various bullet weights, powder charges, etc. It still shoots extremely high. Since these guns were only purchased about a year ago, and they're marked "Performance Center," would S&W consider taking them back for a barrel re-fit or something? Dad's gun remains unfired, but since they have consecutive serial numbers, I would think they'd share similar symptoms. I'm amazed at the light trigger pulls and smooth actions, but shooting this high at such short ranges isn't acceptable. BTW, Mom can shoot my wife's M34 at 50-feet and score 3-inch groups. Likewise with my Ruger MkII at 1-inch groups. In fact, she wants my Ruger for her self defense weapon because she can shoot it so well. Any advice is welcome.