Steel CASED and steel JACKETED ammo are two different things.
There are tests out on the internet to discover the expected affects of both and to make a dangerous generalization you got to shoot a lot more for the cheaper price. Nobody expects higher accuracy, chamber and barrel life were incrementally shorter, but it wasn't as if either would ruin an heirloom rifle. We're talking ten's of thousands of rounds - which means in the AR the extractor, bolt, and port in the barrel will all suffer regardless. Tens of thousands of rounds means replacing the bolt parts at 25,000, long before the port erodes. And port erosion is a function of heavy shooting schedules where mag after mag is fired, not leisurely target shooting at paper a long distance away.
For the most part most shooters won't even begin to approach the limit of the AR bolt and extractor. For an interesting view of high volume gun use, look up the Henderson Defense threads on rental gun use at the Vegas range. Those guns can put down 200,000 rounds a year - which is about what it would take to get the quick answer about steel cased or bimetal projectile wear in weapons. Those guns are literally shot to pieces, all on brass cased ammo.
While we used to have issues with foreign import ammo with lacquered cases causing a build up of residue they have long ago switched over to a polymer coating and that isn't an issue any more either. So for the most part, shoot all the steel cased or bimetal you like - it would get pretty expensive to begin to measure wear and most of us aren't even equipped or knowledgeable enough to measure it.
I've been shooting steel cased in my new builds and guns - I'm breaking in a new Kahr CW380 precisely because there are some who say it can't be done. I only have a problem with it failing to lock back on the last round, which is indicative of the low power that Monarch loads them - not a steel case. Hornady American Gunner has no problem with that.
Steel cased won't cause your weapon to inordinately wear out decades before it's time. Just don't expect much from it, you get what you pay for.
There are tests out on the internet to discover the expected affects of both and to make a dangerous generalization you got to shoot a lot more for the cheaper price. Nobody expects higher accuracy, chamber and barrel life were incrementally shorter, but it wasn't as if either would ruin an heirloom rifle. We're talking ten's of thousands of rounds - which means in the AR the extractor, bolt, and port in the barrel will all suffer regardless. Tens of thousands of rounds means replacing the bolt parts at 25,000, long before the port erodes. And port erosion is a function of heavy shooting schedules where mag after mag is fired, not leisurely target shooting at paper a long distance away.
For the most part most shooters won't even begin to approach the limit of the AR bolt and extractor. For an interesting view of high volume gun use, look up the Henderson Defense threads on rental gun use at the Vegas range. Those guns can put down 200,000 rounds a year - which is about what it would take to get the quick answer about steel cased or bimetal projectile wear in weapons. Those guns are literally shot to pieces, all on brass cased ammo.
While we used to have issues with foreign import ammo with lacquered cases causing a build up of residue they have long ago switched over to a polymer coating and that isn't an issue any more either. So for the most part, shoot all the steel cased or bimetal you like - it would get pretty expensive to begin to measure wear and most of us aren't even equipped or knowledgeable enough to measure it.
I've been shooting steel cased in my new builds and guns - I'm breaking in a new Kahr CW380 precisely because there are some who say it can't be done. I only have a problem with it failing to lock back on the last round, which is indicative of the low power that Monarch loads them - not a steel case. Hornady American Gunner has no problem with that.
Steel cased won't cause your weapon to inordinately wear out decades before it's time. Just don't expect much from it, you get what you pay for.
Maybe the new carbine or pistol will fair better with it.
