|
|
08-10-2018, 07:36 AM
|
Member
|
|
|
Join Date: Mar 2011
Location: Virginia
Posts: 116
Likes: 2
Liked 125 Times in 48 Posts
|
|
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?
|
08-10-2018, 07:44 AM
|
|
Member
|
|
|
Join Date: Dec 2017
Location: Illinois
Posts: 240
Likes: 802
Liked 510 Times in 155 Posts
|
|
Bore the chambers short and call it a 38, I have not seen that before.
|
08-10-2018, 07:48 AM
|
|
Moderator
|
|
|
Join Date: Jun 2007
Posts: 26,911
Likes: 993
Liked 19,047 Times in 9,316 Posts
|
|
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
|
The Following 4 Users Like Post:
|
|
08-10-2018, 08:33 AM
|
Member
|
|
|
Join Date: Mar 2011
Location: Virginia
Posts: 116
Likes: 2
Liked 125 Times in 48 Posts
|
|
Quote:
Originally Posted by murphydog
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.
|
08-10-2018, 08:49 AM
|
|
Moderator
|
|
|
Join Date: Jun 2007
Posts: 26,911
Likes: 993
Liked 19,047 Times in 9,316 Posts
|
|
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
|
08-10-2018, 10:46 AM
|
Member
|
|
|
Join Date: Mar 2011
Location: Virginia
Posts: 116
Likes: 2
Liked 125 Times in 48 Posts
|
|
Quote:
Originally Posted by Struckat
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.
|
08-10-2018, 12:25 PM
|
|
Moderator
|
|
|
Join Date: Jun 2007
Posts: 26,911
Likes: 993
Liked 19,047 Times in 9,316 Posts
|
|
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
|
08-10-2018, 12:49 PM
|
Member
|
|
|
Join Date: Aug 2016
Posts: 350
Likes: 20
Liked 481 Times in 142 Posts
|
|
.38 Special +P would be something greater than .38 Special but below .357 Magnum. So a +P+ would be beginning .357 Mag load??
|
08-10-2018, 04:26 PM
|
Member
|
|
|
Join Date: Mar 2011
Location: Virginia
Posts: 116
Likes: 2
Liked 125 Times in 48 Posts
|
|
Quote:
Originally Posted by fortyshooter
.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.
|
08-10-2018, 05:30 PM
|
Member
|
|
|
Join Date: Aug 2007
Location: Oklahoma
Posts: 8,161
Likes: 3,622
Liked 5,211 Times in 2,174 Posts
|
|
Quote:
Originally Posted by fortyshooter
.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
|
08-10-2018, 05:42 PM
|
|
Member
|
|
|
Join Date: Sep 2005
Location: yonder
Posts: 2,223
Likes: 4,196
Liked 3,548 Times in 950 Posts
|
|
Added pics for reference. Ranger "+P+" 110 Gr. loads.
..sorry about the blurry pic
|
|
Posting Rules
|
|
|
|
|