let's count with guns and gun terms.

[Cee Zee]

Smith & Wesson 656-5 revolver in .357 mag.
Smith & Wesson 657 Revolver in .41 mag.

 

[Legionnaire]

Tikka M658 rifle.
Smith & Wesson 659 pistol.
Mauser 660 rifle.

 

[JMACDONALD]

Smith Wesson 66-1

 

[bannockburn]

Verona Model 662 SxS shotgun

 

[Cee Zee]

Lyman Cast Bullet 663 Top Punch

 

[Legionnaire]

Crosman 664GT air rifle.
.665 = constriction of a turkey choke.
H&R 666 revolver.

 

[bannockburn]

S&W Model 66-7 revolver

 

[Cee Zee]

Beretta 686 Silver Pigeon I Sporting shotgun

 

[19-3Ben]

^^^ well, while you're at it, there's the 687 Silver pigeon III.

 

[Cee Zee]

Ooops. I guess I looked too far ahead. I shouldn't look at numbers when my eyes aren't open yet. Let's try this again the right way. Instead of "686" I'll do "668" this time.

Taurus 668 6" Stainless .357 magnum revolver

We can come back to the Beretta shotguns later.

 

[splattergun]

S&W 669 semi auto pistol
Winchester 670 bolt action rifle
DD-671, designation of Navy destroyer "USS Gatling", named for Dr. Richard Gatling, inventor of the Gatling gun.

 

[Legionnaire]

Noble 672 shotgun.
Remington 673 rifle.

 

[Cee Zee]

Beretta Carbine Cx4 Storm C5A674 Stock Spacer

 

[bannockburn]

Stevens Model 675 pump action 12 gauge shotgun.

 

[Legionnaire]

H&R 676 revolver.
Rossi M677 revolver.

 

[splattergun]

Ruger Mark 678 competition .22 pistol
Mossberg 679 lever action rifle
Beretta 680 shotgun

 

[Cee Zee]

Smith & Wesson Model 681 4" brl .357 mag

 

[Legionnaire]

Beretta 682 shotgun.
SACO Defense Model 683 smg.

 

[splattergun]

Sears & Roebuck Model 684 shotgun,
SKB 685 o/u shotgun
S&W model 686 revolver

 

[Cee Zee]

And now we come back to the :

Beretta 687 Silver Pigeon

 

[WestKentucky]

.688 is the bore diameter for most paintball guns.

 

[Candyman87]

Taurus Model 689 revolver

Beretta 690 Field III

 

[WestKentucky]

. U 91 is standard bore size for a "full" remchoke

 

[Legionnaire]

^^ I think WK means .691

Beretta 692 shotgun.

 

[bannockburn]

Daisy Model 693 CO2 BB pistol