AR-15 500 Round Cast Bullet Test
Recently I was wondering about shooting cast bullets out of an AR-15. In checking the web all I found was much discussion about how you could not use cast bullets in an AR-15, and like most things on the web, there were lots of opinions with few them based on actual information. So I thought I would conduct a test of cast bullets in the AR-15 by firing 500 rounds through one and see how it went. The primary focus of the test was to see if cast bullets could reliably function in an AR-15, with accuracy a secondary issue.
I used a Colt A2 upper with a 20” barrel with a 1 X 12” twist. It appears to be a Model 1 Sales barrel that does not appear to be chrome lined. I shot all targets at 25 yards because as stated the primary goal of the test was 100% functioning of the gun with cast bullets, not finding the most accurate load. I also decided not to clean the gun during the duration of the test to see if a build up of lead or lube would cause any malfunctions.
I got on EBAY and found a Lyman 224415 single cavity die and a 224 sizing die for sale at a very reasonable price, so I bought them.
http://castboolits.gunloads.com/imag...dbe76e43ac.jpg
My standard load for 223 is 26 grains of WW-748 behind either a 55 grain or 62 grain milsurp bullet. When I tried that load with the cast bullet, I ended up with a silver soldered flash hider, and no idea where the bullets were impacting.
http://castboolits.gunloads.com/imag...dc0231505a.jpg
I reduced the load down to 16 grains of 748 and then worked back up until it would reliably eject the case and load another round. I found that with 22 grains of WW-748, the load would reliably function in the Rock River AR-15 Pistol I was using at the time for load development (the idea being a AR-15 pistol would be more finicky than a rifle, so if it worked in the pistol it would in the rifle).
Due to the blunt nose of the Lyman bullet, I was only getting the bullets to feed properly about 80% of the time. I then tried a custom Lee Bator bullet that Midsouth Shooters Supply offered, while it was more accurate than the Lyman, but had to be hand fed to work.
http://castboolits.gunloads.com/imag...dbdab4da94.jpg
I decided to spend real money and bought the RCBS 55 grain spire point bullet mold and that solved all my feeding problems.
http://castboolits.gunloads.com/imag...dbec92efc6.jpg
The bullets were cast primarily out of wheel weight with a little linotype mixed in, they were sized .224 and had gas checks placed on them during sizing. They were only casually inspected for wrinkles, voids and so on. Cases were military surplus brass, Reloading the cases followed the standard procedures, with the exception of using a Lyman M die to expand the case necks and then a lee factory crimp die to crimp the reloaded cases.
I proceeded to shoot the first 250 rounds in intervals of 10 or 20 rounds at a time while I was shooting other stuff (I am retired so I have lots of time on my hands). I then decided to shoot the other 250 rounds in a single setting in a very short amount of time to maximize the stress on the gun.
http://castboolits.gunloads.com/imag...ef8da1abad.jpg
The 250 rounds were fired in about 15 minutes with the barrel too hot to touch by the end of it. There were no malfunctions of any kind during the test.
Here is a picture of the bolt at the end of the 500 round test.
http://castboolits.gunloads.com/imag...ef3f87ab8b.jpg
I was able to put 500 rounds of cast bullets through an AR-15 without cleaning it and did not have any problems or malfunctions at all. The test showed (to me at least), that AR-15's can be made to work consistently with cast bullets. In regard to accuracy, I didn't see any significant change in accuracy, but I wasn't really testing for it.
I have submitted a more detailed version of this post to cast pics. It includes more detailed photos of the bullets, targets and so on.