9mm Ballistics Help

[philadelphia patriot]

First, please sustain from making any comments about carrying a larger caliber firearm. I own firearms in larger calibers too.

I have a S&W M&P 9 (full size). I normally carry 124 grain +p Federal HST which produces (at the muzzle) 1200 feet per second (fps) and 396 ft/lbs.

I have a box of Speer Gold Dots in 115 grain +p+. This round produces (at the muzzle) 1300 fps and 432 ft/lbs.

Will the 115 +p+ rounds inflict a considerable amount of damage to my M&P 9 or will I be fine? Also Speer Gold Dots in 124 grain +p produce (at the muzzle) 1220 fps and 410 ft/lbs, and are a little more powerful than Federal HSTs.

Note: I usually only run 10 rounds of SD ammo through my carry guns (once every 3-6 months) to test functionality and will NOT be feeding my M&P or other carry guns a steady diet of +p or +p+.

[carwash]

When in doubt consult the manual-

"Plus-P-Plus” (+P+) ammunition must not be used in Smith &
Wesson firearms. This marking on the ammunition designates that
it exceeds established industry standards, but the designation
does not represent defined pressure limits and therefore such
ammunition may vary significantly as to the pressures generated
and could be DANGEROUS."

http://www.smith-wesson.com/wcsstore...l%20Manual.pdf

[SwampFoxZ71]

When in doubt consult the manual-

"Plus-P-Plus” (+P+) ammunition must not be used in Smith &
Wesson firearms. This marking on the ammunition designates that
it exceeds established industry standards, but the designation
does not represent defined pressure limits and therefore such
ammunition may vary significantly as to the pressures generated
and could be DANGEROUS."

http://www.smith-wesson.com/wcsstore...l%20Manual.pdf

^^^

That. To be honest, I never worry or mess with +P ammo unless using a .357 mag where I can then safely use 38. 38+P or .357 mag w/o problem. To me, just really not worth worrying about the safety factor and wear /tear on my semi's.

[jthrelf]

Most manufacturers will say no +P+ because none are SAAMI rated so it's a cover their ass kind of thing. Shooting 10 rounds a month I doubt you would have a problem. That said, I'm more of a 124gr 9mm guy and the HST 124gr +P is a fine round. You won't gain a ton of performance with a higher pressure load and you may sacrifice your follow up shot speed. Basically no reason to switch especially if you have a few boxes stocked. But you could if you wanted.

[philadelphia patriot]

Thanks for everybody's input. I just emailed Underwood Ammo to see if anybody ever used a S&W M&P 9 to shoot his 124 +p+ round. 465 ft/lbs at the muzzle is not something to laugh at.

[Pizza Bob]

I think you meant "abstain", meaning to refrain from doing something. But I am going to do it anyway...

It constantly amazes me that people buy one thing, when in reality they want something else. If you want that kind of ME, buy a gun chambered in a caliber that can produce it without stressing the engineering limits of the firearm. If a nominal 9mm bullet diameter trips your trigger, try .357 Sig or .38 Super.

As has been pointed out, while +P ammunition has SAAMI standards, +P+ does not, so it's a crap shoot as to how much pressure that +P+ ammo you want to shoot in your plastic fantastic produces.

As a footnote, I was unaware that Speer produced any +P+ ammo in their Gold Dot line. Couldn't find it in their product listings on their website. Where did you come by this?

+P+ ammunition, aside from that made by specialty manufacturers like the Underwood you are considering, is usually manufactured to order for specific LE agencies that use a specific weapon's platform. It is usually done with the weapons manufacturer's tacit consent and made to be used in that firearm, by that agency, only. Sometimes product overruns appear on the civilian market. You won't find any in any of my guns. YMMV.

Adios,

Pizza Bob

[USMC3531]

I wouldnt use any +P+ in any semi auto you cant always see how much it beats up your frame until its too late.

[ERMedic]

Speer absolutely makes +P+ ammo. I gave him the box of it
It's also what's in my G19. The store I purchased it from would only sell it to LEOs. Speer specifically had it marked as "law enforcement" ammo.

[Pizza Bob]

Speer absolutely makes +P+ ammo. I gave him the box of it
It's also what's in my G19. The store I purchased it from would only sell it to LEOs. Speer specifically had it marked as "law enforcement" ammo.

I didn't question whether they made it or not. It is not part of their civilian line. As you indicated it is for LE use only, and I'd wager, specifically for one agency with a specific weapon's platform. Whether that is a G19 or not is anybody's guess. As I said, it's a crap shoot. If you feel the need for more power, buy a gun chambered for something hotter.

Adios,

Pizza Bob

[dkf]

SAAMI does not recognize +P+ so the specs are kinda up in the air it.

I would shoot "+P+" loads from the major manufacturers like Speer, Federal, Winchester and etc. If you actually chrono some of the +P+ rounds from the manufacturers I mentioned you will see they are often right on par velocity wise with several of the +P ammo out there.

The 124gr +P HST is a very good load and honestly I don't see a reason to deviate from that.

The Underwood is going to be loaded to max or over max. He doesn't send his ammo off for pressure testing. Pressure testing costs money and a small boutique ammo maker like Underwood can't afford ot send his different loads off for testing. Thus I have no interest in it.

Speer absolutely makes +P+ ammo. I gave him the box of it
It's also what's in my G19. The store I purchased it from would only sell it to LEOs. Speer specifically had it marked as "law enforcement" ammo.

AKA ammo that comes in 50rd boxes. Speer rakes the "civilian" through the coals buying overpriced 20rd boxes and then sells 50rd boxes to "Law Enforcement". A similar policy from Federal with the HST. I only buy the 50rd boxes because I don't like to piss my money away. Some larger departments do on the rare occasion work with the manufacturer on a tweaked load (usually large departments) however the "civilian" usually only can get their hands on any remaining overrun ammo.