Upgraded weapons

The following is a list of the Pack-a-Punch weapons and the differences between them and the normal version of the weapons.

Call of Duty: Black Ops
For a chart depicting the stats of each weapon before and after it has been Pack-a-Punched, click here.

Pistols
M1911 vs Mustang and Sally

Python vs Cobra

Five-Seven vs Ultra

Dual wield Five-Sevens vs Ultra & Violet

B23R vs B34R

Executioner vs Voice of Justice

KAP-40 vs Karmic Atom Perforator-4000

SMGs
MP5 vs MP115 Kollider

Chicom CQB vs Chicom Cataclysmic Quadruple Burst

AK74U vs AK74-FU2

Assault Rifles
FN FAL vs EPC WN

SMR vs SM1L3R

MTAR vs Malevolent Taxonomic Anodized Redeemer

Type 25 vs Strain 25

M8A1 vs Micro Aerator

M16 vs Skullcrusher

M14 vs Mnesia

Galil vs Lamentation

LMGs
HAMR vs SLDG-HAMR

RPD vs Relativistic Punishment Device

Snipers
DSR-50 vs Dead Specimen Reactor 5000

Barrett M82A1 vs Macro Annihilator

Shotguns
Olympia vs Hades

R-870 MCS vs Refitted-870 Mechanical Cranium Sequencer

M1216 vs Mesmerizer

S12 vs Synthetic Dozen

Special
RPG vs Rocket Propelled Grievance

War Machine vs Dystopic Demolisher

Ballistic Knife vs Krauss Defibrillator

Wonder Weapons
Ray Gun vs Porter's X2 Ray Gun

Trivia

 * Some Pack-a-Punch weapons have the number 115 in their name, a reference to Ununpentium, also known as Element 115, which was related to the creation of the zombies, teleporters and the Wonder Weapons. Also, if one goes to the monitor (after breaking out of the chair at the main menu), one can access a document by Dr. Maxis saying that element 115 can enhance weaponry.
 * A few Pack-a-Punch weapons have numbers that stand for letters, a reference to "leet-speak", a symbolic alphabet that uses a combination of ASCII characters to stand for letters (5 = S, 3 = E, |-| = H, etc.). For example, a Pack-a-Punched AUG is the AUG-50M3, which can be translated as AUG-SOME, which is similar to "awesome".
 * It can be said that on Call of Duty: Black Ops Wii, it seems that all the Pack-a-Punched weapons are green except the Porter's X2 Ray Gun which is black and orange, however this may just be a visual or texture glitch.
 * Weapons from Call of Duty: World at War have a certain Pack-a-Punch camouflage scheme, while the weapons from Call of Duty: Black Ops have a different camo scheme. In Call of Duty: World at War, the camo is a metallic tone, while in Call of Duty: Black Ops, the camo is more of a machinery tone with (what looks like) circuitry covering it.
 * In Der Riese, it is possible to Pack-a-Punch a Mosin-Nagant, a Sawed-Off Double-Barreled Shotgun w/ Grip (The Snuff Box) and an Arisaka (The Eviscerator) through modding (which were cut from the final game).
 * Mustang and Sally is a reference to the song Mustang Sally. On the front of the game's box, the soldier is holding an M1911 that has the word "SALLY" and the number eight in tally marks carved in the side.
 * The Typhoid and Mary is an obvious reference to the actual person Typhoid Mary.
 * The Tokyo and Rose are likely a reference to the actual people nicknamed Tokyo Rose.
 * The Calamity and Jane are likely a reference to the actual person Calamity Jane.
 * Just like the Ray Gun, the Mustang and Sally pushes the user back when fired.
 * The Ray Gun and the Zap Gun Dual Wield are the only Wonder Weapons when Pack-a-Punched have the prefix, Porter's X2.
 * Many Call of Duty: Black Ops guns including the AK47, Kiparis, Stoner63, Skorpion, WA2000, and a removed gun called the Sabertooth were once available in zombies mode with their own pack-a-puched versions, as according to the game files.
 * The Widow Maker is not likely a reference to the horse of tall tale hero Pecos Bill.
 * The Widow Maker is a somewhat common term for something that kills many men.
 * The Widow Maker might also reference the Martin B-26 Marauder,due to the large number of crashes during take offs and landings.
 * Some of the new weapons in Black Ops II can be Pack-a-Punched more then once, resulting in different attachments.
 * Some of the Pack-a-Punched Weapons in Call of Duty: Black Ops II Zombies have their designative acronyms spelled out (i.e. RPD being the "Realitivistic Punisment Device."