Smith & Wesson Forum

Go Back   Smith & Wesson Forum > Smith & Wesson Revolvers > S&W Revolvers: 1980 to the Present
o

Notices

S&W Revolvers: 1980 to the Present All NON-PINNED Barrels, the L-Frames, and the New Era Revolvers


Reply
 
Thread Tools Display Modes
  #1  
Old 08-10-2018, 07:36 AM
Vilkus Vilkus is offline
Member
Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+?  
Join Date: Mar 2011
Location: Virginia
Posts: 116
Likes: 2
Liked 125 Times in 48 Posts
Default Tested for +P+?

I was cleaning my M-640 38 special and noticed "tested for +P+ written on the frame.
I seem to remember reading somewhere that there is no industry standard pressure for +P+ ammo.
If that's the case, how would S&W know what pressure to proof the gun for?
Reply With Quote
  #2  
Old 08-10-2018, 07:44 AM
Struckat's Avatar
Struckat Struckat is offline
Member
Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+?  
Join Date: Dec 2017
Location: Illinois
Posts: 240
Likes: 802
Liked 510 Times in 155 Posts
Default

Bore the chambers short and call it a 38, I have not seen that before.
Reply With Quote
  #3  
Old 08-10-2018, 07:48 AM
murphydog's Avatar
murphydog murphydog is offline
Moderator
Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+?  
Join Date: Jun 2007
Posts: 26,782
Likes: 935
Liked 18,873 Times in 9,241 Posts
Default

The best theory about this mark is that it refers to the 110 gr US Treasury issue .38 Special load of the era that was labeled +P+. It was present on a small number of the early CEN prefix 640s, and removed once the factory lawyers found out about it (my theories only ).
__________________
Alan
SWCA LM 2023, SWHF 220
Reply With Quote
The Following 4 Users Like Post:
  #4  
Old 08-10-2018, 08:33 AM
Vilkus Vilkus is offline
Member
Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+?  
Join Date: Mar 2011
Location: Virginia
Posts: 116
Likes: 2
Liked 125 Times in 48 Posts
Default

Quote:
Originally Posted by murphydog View Post
The best theory about this mark is that it refers to the 110 gr US Treasury issue .38 Special load of the era that was labeled +P+. It was present on a small number of the early CEN prefix 640s, and removed once the factory lawyers found out about it (my theories only ).
My gun is a CEN prefix gun. Your theory sounds reasonable to me, especially the lawyer part.
Reply With Quote
  #5  
Old 08-10-2018, 08:49 AM
murphydog's Avatar
murphydog murphydog is offline
Moderator
Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+?  
Join Date: Jun 2007
Posts: 26,782
Likes: 935
Liked 18,873 Times in 9,241 Posts
Default

Here is an old thread from here, that also references a 147 gr. 38 Special +P+ loading:

38 +P+ 110gr JHP Treasury Ammo Test
__________________
Alan
SWCA LM 2023, SWHF 220
Reply With Quote
  #6  
Old 08-10-2018, 10:46 AM
Vilkus Vilkus is offline
Member
Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+?  
Join Date: Mar 2011
Location: Virginia
Posts: 116
Likes: 2
Liked 125 Times in 48 Posts
Default

Quote:
Originally Posted by Struckat View Post
Bore the chambers short and call it a 38, I have not seen that before.
My 640 (no dash) was produced around 1990 before S&W stretched the frame for the 357 mag. I do believe that they made a 38 sp. chambered 640-1, which had the longer frame, but that's not the model I have.

I found the thread about the +P+ loads interesting.
I currently use Buffalo Bore's take on the FBI load which they claim 1040 fps out of a 2 inch Mod 60.
Reply With Quote
  #7  
Old 08-10-2018, 12:25 PM
murphydog's Avatar
murphydog murphydog is offline
Moderator
Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+?  
Join Date: Jun 2007
Posts: 26,782
Likes: 935
Liked 18,873 Times in 9,241 Posts
Default

The later 640 (J Magnum frame) that was in .38 Special was the -2, an approved NYPD backup gun back in the day.

Buffalo Bore published velocities have been found to be pretty accurate; how they do it at accepted +P pressures is the mystery .
__________________
Alan
SWCA LM 2023, SWHF 220
Reply With Quote
  #8  
Old 08-10-2018, 12:49 PM
fortyshooter fortyshooter is offline
Member
Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+?  
Join Date: Aug 2016
Posts: 350
Likes: 20
Liked 481 Times in 142 Posts
Default

.38 Special +P would be something greater than .38 Special but below .357 Magnum. So a +P+ would be beginning .357 Mag load??
Reply With Quote
  #9  
Old 08-10-2018, 04:26 PM
Vilkus Vilkus is offline
Member
Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+?  
Join Date: Mar 2011
Location: Virginia
Posts: 116
Likes: 2
Liked 125 Times in 48 Posts
Default

Quote:
Originally Posted by fortyshooter View Post
.38 Special +P would be something greater than .38 Special but below .357 Magnum. So a +P+ would be beginning .357 Mag load??
Interesting observation. Just for chuckles I looked at velocities of 158g 357 mag bullets fired from actual 2 inch barrels. From three different manufacturers Speer, Rem. and Magtech, they got 1003 fps, 1115 fps and 1188 fps with factory ammo.


The aforementioned 38 special +P 158g swchp from Buffalo Bore at 1040 fps, is nipping at their heels.

Other tests of 158g 38 special +P ran around 800 fps.

So you are probably correct. 38 sp. +P+ would be like 357 light, I would think.

The velocity readings I got are off the net, not from my personal tests.
Reply With Quote
  #10  
Old 08-10-2018, 05:30 PM
OKFC05 OKFC05 is offline
Member
Tested for +P+? Tested for +P+?  
Join Date: Aug 2007
Location: Oklahoma
Posts: 8,158
Likes: 3,605
Liked 5,199 Times in 2,172 Posts
Default

Quote:
Originally Posted by fortyshooter View Post
.38 Special +P would be something greater than .38 Special but below .357 Magnum. So a +P+ would be beginning .357 Mag load??
A REASONABLE company or loader could load that way but does not have to.
No standard means the loader can do as he pleases and call it +P+. Some might be barely over +P limits while others may equal .357 Proof loads.
__________________
Science plus Art
Reply With Quote
  #11  
Old 08-10-2018, 05:42 PM
jughed440's Avatar
jughed440 jughed440 is online now
Member
Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+? Tested for +P+?  
Join Date: Sep 2005
Location: yonder
Posts: 2,214
Likes: 4,149
Liked 3,533 Times in 947 Posts
Default

Added pics for reference. Ranger "+P+" 110 Gr. loads.

..sorry about the blurry pic

Tested for +P+?-2014-11-10-04-12-39-jpg
Attached Images
File Type: jpg 2014-11-09 09.01.04.jpg (72.8 KB, 33 views)
File Type: jpg 2014-11-10 04.12.39.jpg (93.3 KB, 105 views)
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Tested the new SD9 leejack Smith & Wesson SD & Sigma Pistols 8 04-06-2017 02:04 PM
20 different Ammo tested M&P15-22 Mark15/22 Smith & Wesson M&P 15-22 19 02-24-2016 11:41 PM
Tested my first 223 loads Magload Reloading 24 09-25-2015 07:03 PM
I was tested this morning Mexistrat Concealed Carry & Self Defense 31 09-25-2015 12:41 PM
has anyone tested the shield? birddseedd Smith & Wesson M&P Pistols 23 11-20-2013 10:35 PM

Powered by vBadvanced CMPS v3.2.3
smith-wessonforum.com tested by Norton Internet Security smith-wessonforum.com tested by McAfee Internet Security

All times are GMT -4. The time now is 12:03 PM.


Smith-WessonForum.com is not affiliated with Smith & Wesson Holding Corporation (NASDAQ Global Select: SWHC)