Muzzle Energy question

[pfgrone]

Situation:
New 32acp Beretta 3032 w/ 2.4" bbl. came with printed warning not to use loads exceeding 130 ft/lbs.
goldenloki.com reports 32acp S&B 73 gr. JHP as 135 ft/lbs out of a Kel-Tec P-32 with 2.7" bbl.

Questions:
Is the reported 5 ft/lbs over the recommended max energy a significant enough difference that I should be concerned about damaging my Beretta?
Is muzzle energy purely derived from a formula of from actual tests of some kind?
Are muzzle energy calculations subject to a standard deviation?

Okay, you engineers/physicists, put your heads together and clear this up for me. Please. Thanks.

[WildBill]

Situation:
New 32acp Beretta 3032 w/ 2.4" bbl. came with printed warning not to use loads exceeding 130 ft/lbs.
goldenloki.com reports 32acp S&B 73 gr. JHP as 135 ft/lbs out of a Kel-Tec P-32 with 2.7" bbl.

Questions:
Is the reported 5 ft/lbs over the recommended max energy a significant enough difference that I should be concerned about damaging my Beretta?
Is muzzle energy purely derived from a formula of from actual tests of some kind?
Are muzzle energy calculations subject to a standard deviation?

Okay, you engineers/physicists, put your heads together and clear this up for me. Please. Thanks.

I don't think that 5 ft/lbs is enough to worry about. As you suspected kinetic energy measurements will show a certain deviation so a 5 ft/lb force won't be significant.

Muzzle energy can be easily calculated by multiplying the mass of the bullet times the bullet speed squared divided by 2.

KE = ½mv²

http://en.wikipedia.org/wiki/Muzzle_energy" onclick="window.open(this.href);return false;

[The Annoyed Man]

Don't get AndyC involved in this discussion. viewtopic.php?f=23&t=46111&start=15#p561506" onclick="window.open(this.href);return false;

[pfgrone]

AndyC: Is it muzzle energy that determines whether a particular load is +P? If so, what would be the point at which a 32acp be classified as +P?

[WildBill]

AndyC: Is it muzzle energy that determines whether a particular load is +P? If so, what would be the point at which a 32acp be classified as +P?

The pressure generated upon firing determines if it is +P. The ammo manufacturer will label it so. Here are some for velocity and energy numbers for .32ACP +P ammo from Buffalo Bore. They are around 220 ft/lbs.

http://www.buffalobore.com/index.php?l= ... tail&p=132" onclick="window.open(this.href);return false;

[Dan20703]

Pressure is what determines the +P rating.

I don't think there is a SAAMI +P standard for .32 ACP.

[WildBill]

Pressure is what determines the +P rating.

I don't think there is a SAAMI +P standard for .32 ACP.

[pfgrone]

Oops, "goldenloki.com reports 32acp S&B 73 gr. JHP as 135 ft/lbs out of a Kel-Tec P-32 with 2.7" bbl." My bad, the bullet is FMJ - not that it makes any difference to the information I was seeking.

[The Annoyed Man]

AndyC: Is it muzzle energy that determines whether a particular load is +P? If so, what would be the point at which a 32acp be classified as +P?

The question is more along the lines of, "what would be the point at which a 32acp [would] be classified as just plain P?"

[WildBill]

Oops, "goldenloki.com reports 32acp S&B 73 gr. JHP as 135 ft/lbs out of a Kel-Tec P-32 with 2.7" bbl." My bad, the bullet is FMJ - not that it makes any difference to the information I was seeking.

I think that after all of your calculations you will come to the conclusion that you need a larger caliber.

[WildBill]

AndyC: Is it muzzle energy that determines whether a particular load is +P? If so, what would be the point at which a 32acp be classified as +P?

The question is more along the lines of, "what would be the point at which a 32acp [would] be classified as just plain P?"

Or a -P.

[barstoolguru]

Situation:
New 32acp Beretta 3032 w/ 2.4" bbl. came with printed warning not to use loads exceeding 130 ft/lbs.
goldenloki.com reports 32acp S&B 73 gr. JHP as 135 ft/lbs out of a Kel-Tec P-32 with 2.7" bbl.

Questions:
Is the reported 5 ft/lbs over the recommended max energy a significant enough difference that I should be concerned about damaging my Beretta?
Is muzzle energy purely derived from a formula of from actual tests of some kind?
Are muzzle energy calculations subject to a standard deviation?

Okay, you engineers/physicists, put your heads together and clear this up for me. Please. Thanks.

this is not rocket science, if you build up too much pressure in the breach it will stretch the guns tolerances out. If the gun is limited to a certainty bullet load/speed and you want big/better get a bigger gun. It has limits because for safety reasons. 5 ft per seconds in nothing but 100 ft or better I would wonder with a small cal. Like that

[pfgrone]

I think that after all of your calculations you will come to the conclusion that you need a larger caliber.

I knew someone could not keep from suggesting a larger caliber. When my 70 year old hands with arthritis finally could no longer take the recoil from my dearly loved 38 Spl snubby, I downgraded to 380. By the time my hands were 75 years old, I had tried 4 different 380's and couldn't grip them tight enough to keep from getting stove pipes, etc.. So I am now down to a 32 acp and glad I can shoot it. In five more years, I may be shooting rimfires. We do what we can.