What do all of you think about the steel case rumor?

Use a borescope to check out your chamber and examine your bolt faces under a microscope before and after shooting a lot of steel ammo and you won't think it's a rumor anymore.

First off, steel core ammo is VERY DIFFERENT than steel cased ammo, which I'm not going to get into, because that's not what you asked about... Just pointing out that fact since some of the other answerers are idiots and got these confused.

That said, steel cased ammo is generally not soft enough to obturate properly (expand to seal the chamber), which will allow gas blow-by. This will scorch and pit your chamber and bolt face. Pitting around the primer pocket is also more common, because the steel primer pocket does not deform properly to seal around the primer body under pressure. Pick up an older SKS and you can easily tell if it has fired a lot of steel ammo, simply by the pitted ring surrounding the firing pin. Chambers that have fired a lot of steel cased ammo, even zinc coated steel, will generally show much more wear than an all brass firing chamber. In general, all of my rifles have a mirror polished chamber, maintaining that quality of finish (beneficial for cleaning as well as accuracy) is impossible with steel case ammo.

No, in general it won't effect your accuracy as far as general plinking goes. However, since the chamber seal won't be regulated, you'll get a LARGE deviation in muzzle velocities from shot to shot (high ES), which will diminish your accuracy. That said, if you're shooting steel cased surplus junk, you're probably not too concerned with accuracy, but rather just looking for some inexpensive plinking fun.

Beyond that, steel case ammo can't be reloaded. A shooter that does a lot of high volume plinking, i.e. would benefit from shooting CHEAP steel cased ammo, should 1) be reloading their own ammo to save money, or 2) if they DON'T reload, should be collecting and selling their once fired brass to recoup a bit of their ammo cost. There's a great market for once fired, deprimed brass. In fact many gun shops will buy back your once fired brass, or give store credit towards new ammo. With steel cased ammo, you don't have any of these options.

Sounds like somebody fired steel case down a non military. Then noticed the fired cases bear lots of blown back smoke? Or, had to blame something for a broken extractor? Steel cases only present the same problem I've had with a Swiss Vetterli. This 100 plus year old rifle originally used copper cased rimfire. Converting to centerfire allows use of reformed brass. However, the brass expands slower than copper. Each time I fired? The brass exhibited plenty of smoke on it. Sometimes sending some visibly out the back of chamber. The solution there was to wrap rice, or cigarette paper around the cartridge neck and bullet. Let alone the other factor may be that the chamber does exhibit wear and pitting. Due to age and corrosive propellants.

The same could be said for steel cased. Although I fire steel Romanian 8mm down Gew 88.'s and 98's. With no troubles nor blow back shown.

I hadn't heard this rumor before. I have shot a metric assload of steel cased ammo through a number of different guns ranging from 1911 and Glock pistols to select fire M16s and PKM belt fed machine guns and have never seen any issues from using steel cases. I also have over 10 years experience as an armorer and custom gunsmith. Sounds like a story cooked up by someone trying to sell higher priced ammo for practice when they didn't have any steel case ammo in stock.

I had an extractor break after around 1500 rounds of steel cased ammo through a Bushmaster AR, Bushmaster sent me a replacement that had the improved O ring and spring, and I haven't had an issue since. I don't know if the failure was due to the steel cases or the old style extractor.

ALL of my commie rifles shoot steel cases without a single issue. My HK pistols can not chamber steel cases at all, no matter what caliber. My CZ pistols shoot steel cases just fine no matter what caliber.

The "problem" seems to be extractor damage on older rifles and pistols that were made before steel ammo became popular. I have several older .223s, 9mm, and 45acp. I have yet to have any problems. Though I have had associates whom have had problems. Once the extractors were replaced with new ones no problems. If I ever do, I will repair them with new parts. I want to be able to shoot whatever is available if needed. If I have to baby a firearm to keep it working I'll get rid of it.

I have heard this rumor. It is total BS. The casing may be steel, VERY THIN steel. But.....so is the chamber. MUCH thicker steel. Also all ammunition is slightly undersized. If not it wouldn't fit in the chamber. I read in a magazine recently (Guns & Ammo maybe??) where the editor was responding to someone asking about this, particularly about the extractor being damaged by steel case. He said that you would have to fire tens or hundreds of thousands of rounds before it would ever even possibly be an issue. By then you'd probably have to replace your extractor and barrel and everything else anyway. Warsaw Pact forces used steel case ammo in a lot of military guns, firing full auto for extended periods. Never heard of any issues arising with them caused by the steel cases. And as far as something about less of a gas seal and not using in matches....pffffft. Hornady just came out with a new line of match ammo, just for shooting in matches, and it has steel cases. They call it of all things....Steel Match.

Never heard the rumor that steel cases ruins a gun. I can't imagine a situation where it could occur unless you left it chambered and it corroded into the chamber.

I think I have heard that steel "Core" ammo ruins guns due to the fact that steel does not deform as well as copper alloy. Which in turn erodes the rifling on the barrel a lot faster.

Steel cased ammo will also not have the same pressure as brass because it does not expand the same so you will not get an accurate pressure seal during powder ignition.

But you can't beat the price on some of this stuff for an old beater rifle. For match shooting -- no!

The way I figure it, the cases are mild steel and if your gun is softer than that, you need a better gun.

I've never heard of this, the only fact that I've heard about steel case ammo is that it sometimes has trouble feeding in non-military firearms.