S&W 64 sight regulation

[Thumbcocker]

My vacation present to myself was a Smith 64. I suspect it is a police or security trade in. Anyway at 25 yards it prints over 1/2 of a paper plate high and left with 150 grain wadcutters over 3.0 of promo and 160 grain rfps over 4.0 of 231. I am loading some Lee 105's over 4.4 of promo to try.
I was hoping that this gun would be on or close at 25 yards with 150 to 160 grain boolits.

Does anyone know what range and loads these guns were regulated for at the factory?

[Der Gebirgsjager]

How depressing! I just looked at S&W's website, and I'm convinced I'll never own one of each.
Anyway, I see that they are still making a Model 64, but it looks different from the ones I remember which had a front sight like half of a coin and the slim barrel.
So...the question would be, is yours brand new, or an older one? If new, I think I'd phone S&W and ask them your questions about the distance at which the sights are regulated, and what load is used. I had a similar problem with a Ruger, and they were happy to share the information on the phone.
I believe that these revolvers are still aimed at the police/security market, and just as the model has changed a little, so have the sights and loads commonly in use. Loads today tend to be hotter, like +P, with a lighter bullet like 125 gr., vs. the was they were back in the '70s and '80s when something like a 158 gr. was more common. A hot load means a shorter amount of time in the barrel and with the older guns they tend to shoot low.
So, depending on if yours is and older one or a newer one, shooting a standard 158 gr. factory load will probably shoot dead on at 15 yards if older, and dead on with a +P 125 gr. if new. Either vintage of revolver will shoot to different points of impact with different loadings. The original model had a rounded front sight like half of a coin and the thin profile barrel. The new version has a ramp sight and heavy barrel. Either way, if previously owned, check to see if the front sight was filed a little bit. Since they don't have an adjustable rear sight, if owners fall in love with a particular load it's not uncommon for them to regulate the P.O.I. to point of aim by filing the front sight....which makes it a bit off for anything else. That's in the nature of fixed sighted revolvers. If your P.O.I. is well centered and only half of a paper plate off at 25 yards, then I'd just adjust my point of aim accordingly. You said left, but that may not be the case with other loads, and the rear sight is not adjustable unless you want to file a bit off the right side of the notch. Windage can also change with loads and bullet weights, so doing lots of shooting with lots of loads until you find something that gives results you are happy with is part of the fun of fixed sighted revolvers.

[Outpost75]

The prime directive of gunsmithing is to ALWAYS WORK ON THE CHEAPEST PART FIRST!

Please do not file on the rear sight notch in the frame to correct windage!!!!~

The way windage is adjusted at the factory is to turn the barrel slightly.

When I worked for Ruger in the 1980s fixed sight revolvers for government contract orders were commonly zeroed using the specified ammunition provided as government furnished material. S&W followed the same general practice. The majority of Model 64s being "cop guns", if is shooting high with 150-grain bullets it was likely zeroed with a lighter, jacketed bullet. Before doing anything I would fire some factory 110-grain or 125-grain JHPs.

While targeting specs varied in accordance with the contract specifics the great majority of .38 Special or .357 revolvers would commonly be shot off sandbags at 20 yards, usually aiming at a 2-inch bull or if targeted at other ranges the aiming point being scaled to one inch per ten yards.

At the 20 yard distance most often used, a 3" circle was printed on the target, surrounding the aiming point and being tangent to it at 6:00. Five out of six rounds were usually required to strike within the 3" circle. The correct front sight height would be determined by firing a ten-board sample of revolvers with the contract ammunition to obtain the correct elevation, that sight then being installed on all revolvers for that batch. Windage adjustments were made, when necessary by rotating the barrel in the frame using directed strikes with a babbit bar against the ejector rod shroud or lug forged onto the barrel.

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In revolvers point of impact for elevation is determined more by bullet weight than velocity. In .38 Special either standard pressure or +P loads of the same bullet weight generally shoot close to the same point of aim. As a general rule heavy bullets shoot higher, lighter bullets shoot lower.

In ordinary production intended for civilian retail sales it was common to use .38 Special 148-grain wadcutter ammunition in .357s also because zeroing doing provides a useful point of impact for most commonly used ammunition. Lead wadcutters also provide a better functional check to detect "spitters" in which a new fit-up might over-rotate the cylinder (Not to exceed about 5 degrees of over-rotation being intended by design to compensate for in-service wear).

To determine how much to adjust the fixed sights use the formula X=RE/D where:

X is the amount of correction needed, such as shortening the front sight to move the impact up, or installing a higher front sight to lower point of impact, or rotating the barrel tighter in the frame, moving the front sight left to move impact to the right, etc.

R is the sight Radius in inches.

E is the error correction needed between point of aim and point of impact, and

D is the target distance.

ALL dimensions are in inches.

In extreme cases an old cop gun may have a bent frame from being used as an impact weapon, and/or the crane may be bent out of alignment. A competent gunsmith can fix these. There is absolutely no reason why a 2-inch .38 snubby cannot be zeroed precisely and shoot accurately. My S&W Model 36 former basket case reworked by Sandy Garrett of NoVa Gun Works now shoots ten-ring, 25-yard groups with wadcutters, and quality defense or service loads should do likewise in a mechanically correct gun.

[Petrol & Powder]

I have a model 64 that will not shoot to the sights with anything other than a full power load.
With a cast SWC that runs right around 160 grains I have to use 4.4 grains of 231 to get a point of aim = point of impact result.

It is the only K-frame I own that behaves that way.

Now, a 4.4 grain load of ww231 with a 158gr LSWC isn't super hot (it's right at the upper limit of standard pressure 38 Special in some of my manuals) and 4.5 is listed as the max standard pressure load in a Winchester manual. That same Winchester manual lists 4.7grs. as the max for +P.

The good news is the gun performs wonderfully as long as I keep the loads near the upper end of standard pressure 38 Special and the model 64 can shoot +P loads all day long with no ill effects.

[Char-Gar]

I bought my 64 new in 2005. The only time it was shot at paper was fast short range DA. Mostly I make various beverage cans jump at 20-25 yards or drop metal plates with a 155-165 cast bullet over 3.5/Bullseye. It works for me.

I will say that how you hold the gun in your hand will make a difference in the point of impact. I have found that grips have a big effect on how I can shoot any particular handgun. Your hand is the only thing connecting a handgun to planet earth.

[Hick]

When I first got my S&W Model 64 it shot about 6" left at 25 yards. I did nothing to fix it. For some reason, as I fired lots more rounds, it stopped shooting left. Maybe because I simply got used to it-- don't know for sure.

[Texas by God]

As they say on Family Feud- "Good Answer!"- from all.

Sent from my SAMSUNG-SM-G930A using Tapatalk

[Reverend Recoil]

Char-Gar offers good advice. Hand grip will affect the point of impact. Try adjusting your grip and work on keeping it consistent shot after shot. It costs nothing.