AR ammo question PICS ADDED

[actionshooter]

I have a RRA LAR-15 coyote carbine.  It doesn't like steel case at all, especially Herters.  Every other shot with that stuff I either got a stove pipe or a FTE.  I only shoot brass now and have never had a problem. 

Look at your brass and if you have lines or scarring, you need a chamber reamer, not uncommon.

[FC]

If your AR won't run steel cases there is either something wrong with it or you don't clean it more than every 20,000 rounds or so...

If you are really concerned you can go to your local auto-parts store and buy a can of carburetor cleaner to give a squirt down the gas pipe every time you clean the rifle. There is a significant difference in price between steel and brass cased ammo, enough to pay for a new barrel or even a new rifle pretty quickly.

[Jburke]

I've used both types without any problems what so ever.  Had the gun for about 4 years and have yet to have any problems shooting steel cases.  I buy a little bit of everything though.  If I see a good sale on herters or other cheap ammo I usually pick some up just for plinking. 

[actionshooter]

A lot of it depends on if your barrel was the 1st to get cut with a new reamer or it was the last. 

[Blacklab]

Congrats welcome to the AR world 

[dscubame]

Herters is steel at Cabelas.  I have bought over 10,000 rounds.  Shoot the heck out of steel it is a AR for heavens sake.

[NaturalSelection]

Feed it what it likes.

I put an AR together at Rainier Arms but had it built for more accurate shooting. WOA 18" ultra match barrel in a 1:7 twist with a rifle length gas system, a fancy expensive match bcg and a nice trigger. Last time a shot a 200 yard target the holes would touch using 75 grain black hills stuff. The bulk stuff goes boom, and is alright for plinking at a 100 yards. But I've only ran brass threw the machine.

And one of my feed ramps is scratching the heck out of my brass and bullet but I don't know what to do about it or if it really matters

[CAMPMEAT]

I use any cheap ammo in my RRA. Haven't tried steel case. Cabales has PMC on sale for $5.99 for 20 rounds. Look it up online. I think you can have it shipped to the store without shipping. www.grafs.com is good too. $5.95 shipping, no tax to your door FEDEX. Cabelas charges sales tax, handling fees etc. www.tacticalammunition.com has 2nds you can bulk  pretty cheap too. They're out of Rainier Oregon I think.

[dscubame]

Feed it what it likes.

I put an AR together at Rainier Arms but had it built for more accurate shooting. WOA 18" ultra match barrel in a 1:7 twist with a rifle length gas system, a fancy expensive match bcg and a nice trigger. Last time a shot a 200 yard target the holes would touch using 75 grain black hills stuff. The bulk stuff goes boom, and is alright for plinking at a 100 yards. But I've only ran brass threw the machine.

And one of my feed ramps is scratching the heck out of my brass and bullet but I don't know what to do about it or if it really matters

I like your build and love Rainier Arms good work.  Just my two cents.... feed ramps are not even necessary your never be mud deep in crap with your AR....scratch the hell out of them it does not matter and shoot steel for the sake of gettig rounds down range on the cheap.  1:7 is necessary only with tracers but not bad to have no harm done and match grade barrel is sweet.  Treat it like a AR it will appreciate the brass and steel without prejudice.