Interesting, and factual, article about +P Ammunition

[HankB]

. . . In some cases (as in many short barreled .38 spl's.) +P is the best way to go if you can shoot it proficiently. I would not however feed any J Frames a steady diet of +P's.

S&W explicitly rates some J-frame .38s as acceptable for +P.

Still, I would suggest that if you want to feed a J frame a steady diet of +P ammo, you purchase a .357 Mag J-frame. Designed to take .357 rounds with a Maximum Average Pressure of 35,000 PSI, a .357 should stand up quite well to regular use of .38 Special +Ps at 20,000 PSI.

(SAAMI standards also recognize .357 loads with a MAP of 45,000 CUP. Now, there's no accepted universal formula I know of for converting PSI to CUP, but pressure tested handloading data I've seen suggests that 45,000 CUP .357s may be "hotter" than 35,000 PSI .357s.)

If you're looking for what the standards actually are (including for proof loads) check out the data at saami.org.

 

[TIMETRIPPER]

IIRC the late Saxon Pig of this forum had a good take on +P ammo. He was very outspoken on it.

John

 

[WR Moore]

I don't think its such a great article.............

This is a terrible article, written in poor style, missing important key elements, and making dangerous assumptions about proof test loads and SAAMI limits and spreading this dangerous information publicly. It should be revised or removed.

Agree. The powder charge in a cartridge doesn't "explode" as a start. Then it goes even further down hill.

It's a pity that Speer took down an extremely detailed explanation of +P from their website. Or at least put it where I couldn't find it again. Especially before I could copy it for reference purposes.

After checking the SAAMI spec sheet for using the piezo-electric measuring system, .38 +P is a 9% pressure increase, 9 mm+P is a 10% pressure increase over standard velocity pressures. In the case of 9 mm, that gets the velocities up to about where CIP loaded ammunition is.