Random House:
13. shoot one's wad, [Informal.] a. to spend all one's money: He shot his wad on a new car.
b. to expend all one's energies or resources at one time: She shot her wad writing her first novel and her second wasn't as good.
c. [Slang: Vulgar.] (of a man) to have an orgasm.
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2006.
http://dictionary.reference.com/browse/wad

To shoot (one's) wad "do all one can do" is recorded from 1914. The immediate source of the expression probably is the noun sense of "disk of cloth used to hold powder and shot in place in a gun."
Wad in slang sense of "a load of semen" is attested from 1920s, and the expression now often is felt in this sense.
Online Etymology Dictionary, © 2001 Douglas Harper
http://dictionary.reference.com/browse/wad

NOAD:
wad - 1: ... • [chiefly historical] a disk of felt or another material used to keep powder or shot in place in a gun barrel. ...
–PHRASES shoot one's wad - spend all one's money.
bolt - ...
–PHRASES ... have shot one's bolt - [informal] have done all that is in one's power.

shoot one's bolt -
Also, shoot one's wad. Do all within one's power; exhaust one's resources or capabilities. For example, They were asking for more ideas but Bob had shot his bolt and couldn't come up with any, or Don't shoot your wad with that article or you won't have any material for the sequels. The first expression comes from archery and referred to using up all of one's bolts (short, heavy arrows fired with a crossbow); it was a proverb by the 1200s. The colloquial variant, dating from about 1900, comes from gambling and refers to spending all of a wad of rolled-up banknotes. Also see shoot the works.
—Amer. Heritage Dict. of Idioms (1997)
http://www.answers.com/topic/shoot-one-s-bolt

Webster's 3rd unabridged:
²wad - ... 1 ... c (1) : a relatively soft plug used to retain a charge of powder, to keep the powder and shot close, or to avoid windage esp. in a muzzle-loading cannon or gun (2) : a disk of felt or paper used to separate the components of a shotgun cartridge or to retain the powder in a blank cartridge ... 2 a : a considerable amount ... b : the amount which one is capable of expending — usu. used with shoot

Chambers:
have shot one's bolt - to have made a last attempt to do something but to have failed.
http://www.chambersharrap.co.uk/chambers/feat...

Pons-Collins:
to shoot one's bolt - (fig) sein Pulver verschießen

Oxford-Duden:
shoot one's bolt - (fig.) sine Pulver verschießen

: : : : : : : im going out on a limb here, but i think it refers to muzzle loading rifles and how in the heat of battle as one is reloading, it was common to forget to drop a ball down the barrel before packing the wadding in. hence a wasted shot.
: : : : : ... The Dictionary of American Slang gives two definitions for "wad": first, "a roll or wad of paper money . . . esp. a lot of it or all that one has," with citations of this use from 1814 through recent times; second, "the mouth. Some use c1885-c1920; obs." No entry for "shoot one's wad" as a phrase.
: : : : Well, boys and girls. I don't want to rock you back on your heels, it may originally have mean guns and money but now "shooting your wad" refers to the male climax. And it's not a good idea to say it in Sunday School. ...
: : ... Seriously, though, has the meaning changed so that it's now unwise to say "He cashed his paycheck and shot (or blew) the whole wad on lottery tickets"?
I think the phrase is "To shoot your load" and ..."to blow your wad".
Male climax vs. losing money (ie: gambling)
http://www.phrases.org.uk/bulletin_board/7/me...

This seems like the primary sense. I support adding the English idiom.

I would assume it probably comes from the wad used in a shotgun, just as the bolt comes from an arrow.

I also have the feeling that the version with 'bolt' may be largely BE (and possibly 'wad' also largely AE), but I'm not sure it's a firm enough distinction to deserve a marking.

If anyone has an additional suggestion for the sense 'spend all one's money,' that would be good, but if not, I think it's a subset of the general sense anyway.

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