[JLStorm]

Im trying to figure out how much lighter a round of 40S&W in 165 or 180 grain is than a 230 grain 45ACP round. Basically I am trying to decide if a magazine of 12 rounds of 40S&W is going to weigh less than 8 rounds of 45ACP.

[LarryS.]

Not enough difference to make me decide on the factor of weight alone.:scrutiny:
Give me the .45!:cool:

[JLStorm]

actually this is just one of many deciding factors...I have it down to two guns and its such a close call I have to make a pro and con list, this is part of it.

[Mad Magyar]

am trying to decide if a magazine of 12 rounds of 40S&W is going to weigh less than 8 rounds of 45ACP.
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Your .40S&W in terms of ammo alone will weigh more, however, the .45acp pistol will be over-all heavier due to its dimensions. I doubt that the size variable will be equal....:) With this consideration, the weight between both will be about the same.....

[W.E.G.]

Total bullet payload

.45 (8 rds @ 230 grains) - 1840 grains
.40 (12 rds @ 180 grains) - 2160 grains

The difference is 0.045 pounds (0.73 ounces) when only bullets are taken into account.

The total payload for brass is probably a little bit higher for the .40 too. I doubt that the extra brass amounts to a tenth of an ounce.

Either choice is good. Carry the one you shoot best.