Sorry if this is redundant, I ran a few searches but I didnt find anything on this...

Today I bought a few boxes of Sellier and Bellot 55gr. .223 at the local gun shop. I noticed that the Jacket of the bullet was almost the same color as the brass.  Why is this - what kind of material do they use in their jackets?  It almost looked like the jacket was made of brass. I have also noticed these goofy looking bullets in some of the White Box Winchester pistol ammo I have bought in the past.  Do I need to worry about this at all?  What gives?

That's because it IS the same color.

S&B 55gr:  Projectile is lead core, STEEL jacket.  They basically assemble the bullet/case and then "brass wash" the whole thing.  Steel is cheaper than copper jackets.

These bullets will NOT fragment but seem to penatrate pretty well.  Kind of like an Armour Piercing .22LR.  Nothing to get excited about.  

I can't comment on the pistol ammo you speak of because I plainly don't know.

The steel won't hurt anything.  Remember it's under the brass.  I have used this ammo in the past.  It is a bit dirty and not loaded as hot as mil-spec, but if the price is good it's pretty good plinking ammo.

newbe is correct, the bullets are steel jacketed, hold a magnet next to one and see. The case is solid brass however, not 'washed' steel. I don't know what the bullet jackets are 'washed' with, it does look like brass and not copper. I think the Winchester Wally World 9mm value packs are constructed the same way. For all I know S&B may be the manufacturer of this ammo as well. I use both extensively and have had no adverse effects from their use. Not as of yet anyway. If your AR barrel is chrome lined don't worry about it. The chrome is much harder than the steel jacket. Now the 9mm barrel, that's another story. I have put maybe 700-800 rounds of this ammo thru my Berreta 92 and have seen no ill effects.

Shabo

Well thanks Y'all, I guess that pretty much answers my bullet question.  And I checked - it does stick to a magnet.  So do I have to worry about it in my unchromed Oly barrel?  Either way, I probably won't be buying too much of it in the future.

The 9mm ammo is not steel jacket.  Try a magnet test.