why is .40 "snappy"? It is because it is modern CORRECT design

[Squid]

for short barrel (<=5") and develops power soon enough to use it, as opposed to blowing out the barrel after bullet leaves?

I'm not really seeing any big diff in "the numbers" for velocity, powder, bullet weight ratios from 9mm,.40,45apc that would make me expect the .40 to be 'snappy'.

Does it accel more in initial stage than the others?

[JeremyS]

I think your idea is correct. High pressure round with quick burning powder. Generally high pressure rounds feel like more of a "snap" and lower pressure feels more like a "push"... also powder burn rates and barrel length affect this, along with the weight of the gun you're shooting and the mass of the bullet.

[RoundEye]

My general understating was that it had to do with speed and bullet weight. Most .40 loads tend to be near supersonic, and typically fire a 160 or 180 grain projectile.

[Dhena81]

I think all .40 tends to be in the upper limits of what the cartridge is safely capable of you never see +P .40 being sold. Why is that? +P .40 I guess is 10mm. So if that theory is correct maybe 9mm would be considered snappy if all 9mm was loaded to the upper safe limits. IDK.

[sd_shooter]

9mm +P is definitely more "snappy" than your Walmart WWB. The trouble is, most people never shoot the +P because they don't see it in stores and even if they did, they wouldn't buy it due to cost. We're stuck with comparing WWB of one caliber vs the other.

Same with 45. +P loads have much more kick than target loads but who's going to spend $40 on a box of ammo just to poke holes in paper!

It would be a fair comparison to try self defense loads of 9mm, 40 and 45 together.

[wash]

I think it's a combination of bullet weight, muzzle energy, barrel twist and the rocket effect created by powder continuing to burn after the bullet leaves the barrel.

Some calibers are just like that.

.454 Casull is a lot snappier than .475 Linebaugh...

[JTROKS]

Shooting my G23 with factory defensive loads is definitely snappier than my full size 1911 shooting the same load. The weight of the pistol is a factor. The 40 S&W is snappier due to higher operating pressure than standard 45ACP loads.

[21SF]

I think your idea is correct. High pressure round with quick burning powder. Generally high pressure rounds feel like more of a "snap" and lower pressure feels more like a "push"... also powder burn rates and barrel length affect this, along with the weight of the gun you're shooting and the mass of the bullet.

Check and mate

[9mmepiphany]

It is because it is modern CORRECT design

No, it is because they took a modern CORRECT design and squashed it into a small enough package to feed through popular 9mm designed pistols.

The .40 design come from a desire to obtain downloaded 10mm performance in a 9x19mm sized cartridge. It isn't like the relationship between the .38spl and the .357mag...where the less powerful cartridge came first.

[dkthree]

.40 is high pressure compared to what? If .45 acp is half the pressure, why is recoil not half? If low pressure is desirable, why aren't we all shooting .45 long colt?

PSI doesn't mean much by itself.

[fanof1911forlife]

I think the perceived snappiness is caused by people shooting plastic guns. My P229 scorpion's alloy frame doesnot jump at all.

[Bhobbs]

.40 is high pressure compared to what? If .45 acp is half the pressure, why is recoil not half? If low pressure is desirable, why aren't we all shooting .45 long colt?

PSI doesn't mean much by itself.

Greater projectile mass. 180 grains in the .40 S&W compared to 230 grains in the .45 ACP.

[snafu510]

A while back I read somewhere that it's not the power difference, but the fact that most .40 guns were originally designed for 9mm and there is a problem in timing with the .40. Something to do with the barrel/link geometry for the 9 not being optimal for the .40. Supposedly one popular gun (I can't remember which) was designed as a .40 first and doesn't have a snappy recoil. The rest were 9's first and their actions aren't quite right for the .40 hence the snappy recoil.

Of course I read it on the internet so it may or may not be legit. This info would be a lot more useful if I could remember which brand supposedly has it right.

Also, I've shot a Glock and an XD in 40 and I never noticed anything "snappy" about them.

[TKM]

The muzzle energy of the 40 followed a big circle from standard 45, down to 9, up to 10, 10 reduced to 40 levels, then manufactured as 40 which produces just about the same energy as the 45 where the whole thing started.


No tax dollars were spared in this process.

[9mmepiphany]

Supposedly one popular gun (I can't remember which) was designed as a .40 first and doesn't have a snappy recoil.

More than one.

The first was the SIG 229, followed by the USP

The S&W M&P is designed around the .40 and many folks will tell you that the M&P40 actually has less felt recoil than the M&P9