David2011
07-29-2012, 02:57 PM
When Nancy Pelosi became Speaker of the House I decided to by my first AR-15 in her honor. One of the local shops had an Olympic K-16 which is a 16" bull barreled flat top with the standard A-2 stock and a free floating handguard. OK, it looked like it should be pretty accurate for varmints so I bought it. I broke the barrel in using Wal-mart cheap Remington ammunition and saved the brass for reloading later. When I started reloading I noticed the brass was pretty hard to resize. Other range pickup commercial brass from other guns was far easier to resize. The brass was bulging just above the web, about .015" larger than other fired brass that I picked up at the range. I put up with it for a while but began to have concerns that it would cause case separations if resized and reloaded more than once.
Recently I called Olympic and discussed what appeared to be an oversized chamber and expressed concerns about the effects of resizing this bulged brass. They had no issues with using handloads in their gun. Their only disclaimer is for damage to the gun caused by reloads. They told me to send the upper in for evaluation. I sent it with a couple of fired factory load cases. The bulge was very evident. I really hated the thought of replacing the barrel because it shot extremely well as long as I used premium bullets like Sierra MatchKings or Hornady V-Maxes. Mil-spec bullets didn't group nearly as tightly as premium bullets but they shot acceptably balancing the cost difference.
I sent the upper in and had it back in about 8 or 10 days. They replaced the barrel and extension and the handguard. I don't know why they replaced the handguard other than I had milled a slot in it to accept a JP swivel stud and Acra-glassed it in for full stability. The replacement had an Olympic swivel stud installed which is not standard on that model so no function was lost.
Before I took it to the range I bore pasted the barrel until it felt smooth. I was hoping that I hadn't lost any accuracy. I mounted a Nikon 6-18x40 scope and boresighted it. The next day at the range I fired a 5 shot group to find the point of impact, using mil spec 55 grain FMJs and my usual charge of Win748 and CCI 400 primers. The group was a bit high and left but "only" a 2" spread. That's better than the old barrel had done with the same load and bullet. I put the crosshairs back on the center of the target and adjusted the knobs to move the crosshairs to the center of the first group. Switching to 53 grain HPBT Sierra MatchKings I fired two more rounds and adjusted the scope again. Those two shots later measured .380" center to center. The last 5 shots, with SMKs again, made a .351" center to center group. While the first barrel shouldn't have had an oversized chamber, I was very pleased that the accuracy of the new barrel was on par with the first one and couldn't have asked for faster service.
While looking into building another AR for competition, I've run across several recommendations for using Olympic barrels as a moderately priced barrel with very good accuracy. They just may be right.
David
Recently I called Olympic and discussed what appeared to be an oversized chamber and expressed concerns about the effects of resizing this bulged brass. They had no issues with using handloads in their gun. Their only disclaimer is for damage to the gun caused by reloads. They told me to send the upper in for evaluation. I sent it with a couple of fired factory load cases. The bulge was very evident. I really hated the thought of replacing the barrel because it shot extremely well as long as I used premium bullets like Sierra MatchKings or Hornady V-Maxes. Mil-spec bullets didn't group nearly as tightly as premium bullets but they shot acceptably balancing the cost difference.
I sent the upper in and had it back in about 8 or 10 days. They replaced the barrel and extension and the handguard. I don't know why they replaced the handguard other than I had milled a slot in it to accept a JP swivel stud and Acra-glassed it in for full stability. The replacement had an Olympic swivel stud installed which is not standard on that model so no function was lost.
Before I took it to the range I bore pasted the barrel until it felt smooth. I was hoping that I hadn't lost any accuracy. I mounted a Nikon 6-18x40 scope and boresighted it. The next day at the range I fired a 5 shot group to find the point of impact, using mil spec 55 grain FMJs and my usual charge of Win748 and CCI 400 primers. The group was a bit high and left but "only" a 2" spread. That's better than the old barrel had done with the same load and bullet. I put the crosshairs back on the center of the target and adjusted the knobs to move the crosshairs to the center of the first group. Switching to 53 grain HPBT Sierra MatchKings I fired two more rounds and adjusted the scope again. Those two shots later measured .380" center to center. The last 5 shots, with SMKs again, made a .351" center to center group. While the first barrel shouldn't have had an oversized chamber, I was very pleased that the accuracy of the new barrel was on par with the first one and couldn't have asked for faster service.
While looking into building another AR for competition, I've run across several recommendations for using Olympic barrels as a moderately priced barrel with very good accuracy. They just may be right.
David