Brass vs. Steel Cased Ammo – An Epic Torture Test

[pepito]

http://www.luckygunner.com/labs/bras...el-cased-ammo/

Short excerpt:
Here’s what we did:

• We acquired four identical Bushmaster AR-15 rifles. We chose the Bushmaster MOE Series AR-15 because it’s a widely available, affordable, and mass-market. We didn’t want something too cheap and of lower quality or something too expensive and of high quality since our goal is to help the most number of people.
• We acquired 10,000 rounds each of the following ammunition (new production):
  
  • Federal 55gr – Brass-Cased – Copper Jacket
  • Wolf 55gr FMJ – Steel-Cased with Polymer Coating – Bi-Metal Jacket (steel and copper)
  • Tula 55gr FMJ – Steel-Cased with Polymer Coating – Bi-Metal Jacket (steel and copper)
  • Brown Bear 55gr FMJ – Steel-Cased with Lacquer Coating – Bi-Metal Jacket (steel and copper)
  
  
• We paired each ammunition type with a specific Bushmaster AR-15 and then fired all 10,000 rounds of it through that particular carbine (except for Tula; more on that below)
• We systematically observed and tested various things, including (more details below):
  
  • At the start: accuracy, velocity, chamber and gas port pressures, chamber cast
  • After 2,000 rounds: accuracy, velocity
  • After 4,000 rounds: accuracy, velocity
  • After 5,000 rounds: throat erosion, chamber cast
  • After 6,000 rounds: accuracy, velocity
  • After 8,000 rounds: accuracy, velocity
  • After 10,000 rounds: accuracy, velocity, chamber and gas port pressures, throat erosion, extractor wear, chamber cast, barrel wear
  
  
• We logged every malfunction of every rifle-ammo combination
• The rifles were cleaned according to a preset schedule and temperatures were monitored and kept within acceptable limits (more below)
• We sectioned the barrels and otherwise made unique observations after the test was complete

[patrick0685]

that was a long but good read

[spyder]

I thought it was a great read. I think the barrel erosion was horrible! I would like to see the same kind of test, but done with the same kind of ammo in all guns, and different kinds of barrels. Chrome lined, the wasp lined, stainless, and then throw in a polyagonal. I would like to see the wear characteristics of a polyagonal.

[NightCat]

Those poor 3 Bushmasters :-(

[SA Friday]

Awesome testing. I get asked about this a lot at work. I can now better answer the questions and point to testing. This got bookmarked on my computer.

[Kaiser.Shooter]

That is a good and detailed testing process, I found out a few months ago about bi-metal bullets( steel jacket copper washed) of the russian made ammo and since that I use it only in my beater ar

[onebadfx4]

An awesome read. Answered lots of questions I have had. Will def never purchase steel cased ammo.

[Singlestack]

I really liked the investigations they performed and in-depth analysis. Biggest surprise to me was the extreme barrel wear...

[rockhound]

I wonder how much of the barrel wear etc. comes from have rounds that are covered in desert sand? if your projectile is covered in silica it seems that might cause more wear than normal.

how many of us have put 2500 rounds downthe barrel of our ARs? apparently they are nearly half shot out.

[cofi]

great read my poor dd barrel has over 7000 rounds of steel case through it and 50k 22lr I'm gonna have to start looking into a replacement soon even though it's still more accurate then I am