Sectional Density

[MaconGuns]

Does it matter in handgun rounds?

It takes a 147 grain in 9mm to equal the sectional density of a 230 grain 45acp and a 180 grain in 40sw to equal the other two.
40 =1.61
45=1.62
9=1.67

 

[steviesterno]

no. short answer, no it does not. Get good HPs that expand and shoot them in important stuff.

 

[MaconGuns]

no. short answer, no it does not. Get good HPs that expand and shoot them in important stuff.

So grain weight has no measurable effect as long as the bullet expands. What percentage of expansion would be acceptable. A 22lr that expands to the size of a 9mm or should we just start at 45?

 

[JBWJr]

45acp, because shooting twice is just silly.

 

[steviesterno]

So grain weight has no measurable effect as long as the bullet expands. What percentage of expansion would be acceptable. A 22lr that expands to the size of a 9mm or should we just start at 45?

No, grain weight effects momentum and speed, and speed is the best thing (mv^2) for causing tissue damage. All pistol rounds suck compared to almost all rifle speed rounds. So I would take 22lr in the form of 5.56 any day over 45 unless I gotta stick it in my pants.

 

[MaconGuns]

No, grain weight effects momentum and speed, and speed is the best thing (mv^2) for causing tissue damage. All pistol rounds suck compared to almost all rifle speed rounds. So I would take 22lr in the form of 5.56 any day over 45 unless I gotta stick it in my pants.

Carrying a rifle into Belks isn't a great decision these days and I prefer to conceal carry.

Based solely off speed then a 5.7x28 would be the perfect pistol round at 2300+ish fps

 

[BobbyJack]

I kinda like that old guys YouTube channel. For the most part he does a good job.

 

[MaconGuns]

I kinda like that old guys YouTube channel. For the most part he does a good job.

Sometimes he's a bit drawn out but seems like he knows what he's talking about. I can deal with long winded videos if I believe I'm learning something.

 

[howl]

SD matters on classic bullet designs when you want to get out of the other side of an animal. The piles of money that have been poured into ammo manufacturers in the last decade have changed that. There are new bullet designs which make SD mostly irrelevant. If you're buying cheap SD of .25 is a good rule of thumb. If not cheap or having a specific purpose, look at specific bullets.