Wikipedia on FMJ

[wacki]

* Because the bullet does not expand as hunting bullets are designed to, FMJ bullets are much more effective at armor-piercing. Similarly, they stand a better chance of reaching through to an enemy that is behind moderate cover, such as behind the sheetmetal of a vehicle, for example.
* They are also more durable and stand up to rough handling on the battlefield.
* Their rounded tips lend themselves to properly riding up the feed ramp of a semi-automatic pistol, whereas hollow-point bullets can sometimes present a somewhat higher risk of jamming.

http://en.wikipedia.org/wiki/Full_metal_jacket_bullet#Advantages

How accurate are these advantages? How much more likely are hollowpoints or all lead solid tipped bullets to jam up? The cover scenario seems like something that the box-o-truth should tackle. I wonder how much of a difference there really is.

 

[Gator]

I'd say that is a pretty accurate entry.

 

[RavenVT100]

It depends. The early 1911s did not feed HP ammo very well without a ramp job. Current 1911s are almost always coming out of the factory with a ramp that will accept most HP ammo. That's one example; I am sure there are others.

As far as the armor piercing thing is concerned, they're right for some cases and wrong for others. FMJ is not "AP" per se, it might move through certain barriers better than HP, but anything you or I would call armor isn't going to be penetrated by ordinary small arms ammo excepting special use rounds.

I see what the wiki author is saying and I mostly agree, so as far as I know it's accurate.

 

[never_retreat]

Just remember from a military perspective there are no lead bullets, all jacketed.

 

[strat81]

Sounds accurate to me.

 

[.cheese.]

the only thing I'd dispute is FMJ going through armor as it depends on the armor and the caliber of a bullet:

ie: a .25ACP HP vs FMJ isn't going to make any difference.... even a .45ACP FMJ vs HP isn't going to get through most modern standard armor.... the only calibers that are likely to make a difference are rifle calibers IMO.

The second part of that sentence is accurate though about it being specifically moderate cover.

 

[Lucky]

Yea maybe change line armour penetrating into deeper penetrating.

 

[JesseL]

I don't think you can have a meaningful discussion of the merits and disadvantages of fmj bullets without making the distinction between fmj round nose and fmj spitzer bullets.

I've also got doubts about how much better non-AP fmj rounds work against armor than soft-point bullets. I just don't see an extra millimeter or two of copper making much difference against hardened steel.