This has been reported on in other threads--FYI,
some two years ago I embarked on a reloading project to specifically evaluate short-barrel revolver ammo performance. Among the firearms I used were
- S&W M&P 340 (scandium, 13.3 oz, 38/357)
- S&W 442 (alum., 14.3 oz, 38S only)
- S&W 60-3" (SS, 23 oz(?), 38/357
- S&W 360 (scandium, 13.3 oz, the 38S-only version)
- S&W 640 (SS, 21 oz(?), 38/357)
I shot several different versions of factory ammo as well, in both 38 and 357 loads, including the (in)famous BB 20A--e.g., the 'heavy 38 Special' 158-gr that runs 1000 fps from a short barrel. (It does.)
Part of the goals of this exercise was to get my hand fully-conditioned for effectively shooting, in a SD fashion, my carry gun--the M&P 340. The criteria for that effectiveness is Old Fuff's quad five drill--5 shots, 5 yards, 5-inch group, 5 seconds or less. I got to that point with the M&P 340. I even got to that point including a reload. I am all fumblefingers, however, and if it comes down to reloading, I plan on having reached the trunk gun (SU-16C) first--at least under certain circumstances.
After shooting a several thousand rounds (including at least 1000 from the 340, 15,000-plus from the 640), I found that a 158-gr. bullet running about 900-915 fps from a 1 & 7/8" barrel (the M&P 340, 13.3 oz) was all I could shoot and still get (up to) ten shots off before my hand was done.
Based on my reloading experience, the best a 38 Special 158-gr. round can do from a 2" barrel is about 860 fps--and that is running the round at CIP 38 Special pressures, not SAAMI 38+P. The typical (Remington) 38+P LSWC-HP round now does about 800 fps.
No one makes a reduced-pressure 357 SD load that runs about 900 fps--but they should, IMO.
So, I now build some 357 ammo using the Hornady / Speer 158-gr. LSWC-HP swaged bulletsd, up to about 915 fps from the nominal 2" barrels of the 340 or the 640. Beyond that, the bullet starts skidding and / or blowing out.
To shoot a 158-gr. bullet running at 900 with basic SD proficiency, from a lightweight takes practice. IMO.
Jim H.