S&W M10 heavy barrel rated for +P ammo?

jack_the_sailor

New member
I'm looking for a used S&W M10 heavy barrel that's rated for +P ammo. How do I know if a S&W M10 heavy barrel is rated for +P ammo, by looking at it? I did a search & found that if it has 3 screws but not all 3 screws. Or made 84 or newer. The suggestion was to call S&W. If I'm at a gunshow on the weekend, S&W wont be open & come monday the gun show wont be in town. I don't think the seller would know or care (they just want to sell the revolver). So how can I tell if a S&W M10 heavy barrel is rated for +P ammo?
 
All heavy barrel model 10's are designed to handle Plus P ammo. The heavy barrel models were introduced after S&W upgraded their K frames to handle plus P. Good luck!
 
When in doubt...

call the Customer Service # @ S&W.

Some of these heavy barrel M10s may be gunsmith built so be careful. Check first and stay safe.
 
I don't understand. Are you telling me to call S&W customer service & ask the question? Or are you telling me to write down the serial # & call S&W customer service? If the latter I'm at a gun show on the weekend & S&W customer service will be closed. Unless they have a service rep available 24/7? This is why I ask the question to be armed with knowlage before I look to buy.
 
You will need the serial # of the gun to be able to tell anything about it's date of manufacture and its original configuration. However, do not expect them to be able to give you this kind of information over the phone and with out charge. These sorts of things often involve going to "the stacks" and looking up the information manually. Colt actually has made a business out of this because of the demand for documentation on their Single Action Army.

Now, customer service may be able to tell you what variation of the model 10 can handle the ammo in quanitity (typically stamped on the frame opposite to the cylinder yoke, you will find 10-X). If you don't see a model number in this location, the gun is probably old (I forget when they first started with model numbers, but 40 or so years ago sounds about right).

To put things in perspective, I have a M10 that my dad had built into a PPC revolver in the late '70s and it is a 10-8. My dad actually aquired a M10 about 5 years ago that was a PD turn-in and it was a 10-2! I don't really care if it will not handle +p loads since the Douglas match barrel is supposed to be used for 148 grain HBWC loads.

You could always avoid this problem altogether by getting a M19 (out of production, but they are all over the place).
 
I've heard that 38 +P ammo works better out of a 38 revolver than a magnum revolver. So the M19 is out. I have a S&W M65 w/ 3" barrel which I'm selling to get a 38. My first weapon was a S&W M19 I cracked the forcing cone with magnum loads so I'm not fond of K frames & I don't know why I got the M65 to begin with? I think I forgot that 38 +P ammo performs better comming out of a 38 than a magnum. Some thing about tolerences of the 38 revolver being made to shoot 38 ammo & 357 magnum being made to shoot 357 magnum ammo. I know you can shoot 38 ammo in a 357 magnum. But 38 ammo pressure is lost. I don't understand why it's so hard to find out if a used S&W M10 heavy barrel can handle +P ammo before I buy 1?
 
Jack-

No worries: if the gun has the model number stamped inside the frame, when you swing out the cylinder, it doesn't matter if it has a heavy or std. bbl. It's okay for Plus P. So saith the factory... several times over the years.

Marking the model number on the frame began in 1957, just about roughly the time that the heavy bbl. was introduced. Chic Gaylord commented on the new, improved steel in the M&P (M10) in his, "Handgunner's Guide", printed about 1960.

THIS APPLIES ONLY TO K-FRAME GUNS: J-FRAMES WEREN'T RATED FOR PLUS-P UNTIL RECENTLY.

But, don't use Plus-P all the time if you shoot a whole lot. The USAF had trouble with M-15's shooting loose when fired a lot with hi-velocity rounds, hence wanted a 9mm auto.

The .357 will do okay with .38 Plus-P's. I saw chronograph results on the M-13 and M-10 with the FBI load when the M-13 was Bureau issue. The lead SWC-HP's went about 910 FPS in the M-10 and some 875 FPS in the M-13. Both had three-inch bbls.

Lone Star
 
Jack, I don't know where you got the idea that the 65 would be inferior to a 38 Special with those Plus P's, but if you want to trade the 65 for a Model 15, let me know.

:)
 
jack

It maybe worth your time and money to get a copy of Supica and Nahas "Standard Catalog of Smith & Wesson - Second Edition". This is a superb reference book of almost every handgun S&W have made with lists of serial numbers. Take it and you can make your own determination (in most cases) about whether or not a pistol is a good buy.

BTW, I have two S&W M65's 3" and I shoot primarily .38SPL out of them. No problem.
 
Jack,

It is my experience that the reason .38's shoot better out of .38 revolvers over .357 is due to the slight additional space the bullet must jump in the cylinder of a .357. It induces "yaw" to the bullet before it hits the forcing cone. The velocity of the round is not affected by this jump. The clearence between the cylinder and forcing cone affects velocity far more.

Also in my experience the difference in accuracy is so small that you can not tell with out a ton of skill and /or a Ransom Rest. Even then there are so many variables you can not be sure if that is the definitive answer.

The biggest reason shooting .38's out of a .357 regularly is frowned upon is that the .38 is shorter and continued use can cause buildup or corrosion. Your .357 magnums to not want to seat properly. Good cleaning practices avoid this problem.

A side note, shooting standard velocity .38's will never affect the longgevity of your revolver, The Plus P's will over time reduce the revolvers ability to stay "tight". The amount you would have to shoot however would would be in the thousands of rounds per year catagory.
 
I would like to thank everyone for their responses. I gotten random firearm info over the years. Some of it gets forgotten only to be remembered when something jogs my memory. There aint no guarantee I recall info properly. When I got the used M65 I had trouble getting magnum rds in the cylinders. The clerk said the previous owner must have shot a lot of 38. rds & that ring bult up. The clerk said shooting magnum rds would take care of that problem. It did. Well I need a second weapon because my primary weapon will need work done. Since magnum ammo is expensive I will be using 38 ammo for practice & 38 +P for carry. So why not sell the magnum & get a 38? It's funny when I started in firearms I learned with a 38 because it wasn't a 357 magnum I didn't like them. Then in the mid 80s most shooters switched to 9mm so did I. I didn't like revolvers. Now that I'm older I'm going back to a 38 revolver. I don't like long hard DA revolver trigger pulls. I guess I'm starting over & going to learn to like long hard DA revolver trigger pulls. At any rate I'll look on the inside of the frame were the (what ever that thing is called that holds the cylinder) for a #10 which is the model # then a - & another #. That should mean the S&W M10 heavy barrel is ok for +P ammo. Thanks for the explinaton of 38/357.
 
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