12-31-2011, 03:24 AM
Build was started with a Stiller Precision lower. Slick side upper with no fwd assist and no dust cover. Sabre 18" fluted barrel with heads aced bolt. Yankee Hill diamond hand guard rifle length. DD low profile gas block. Slash's heavy buffer 11 oz and spring. Magpul PRS stock. ADM 20 MOA scope mount. Bushnell Tactical Elite 6-24x50 mil/mil scope.
Took to the range yesterday to functional check. Didn't take chrono. Used 123 grain Hornady Amax factory ammo. Fired about 20 rounds fouling and getting a good zero. 100 yard zero had quite a few fliers due to breaking in. Finally after 25-30 it came in pretty well. <1 MOA at 100. Was really happy with the results but was curious what it was going to do out at distance. Used the velocity printed on the ammo box, 2580 and figured it was with 24" barrel 1:8.5 twist. Since mine is 18" and 1:7.75 I used 2550 fps for my velocity. Used my JBM ballistic calculator and entered the guessed info.
The ballistic calculator said come up .5 mil for 200 yards. Dialed it in and had a first round hit. Fired a few at 200. Checked the iPhone for 300 and dialed the scope for it. First round hit. Did the same for 400. Second round hit. Same program for 500 yards. 4 rounds to hit 500. 1 of those 4 was a hit on the target stand. Got dialed in good and shot swingers at 400 and 500. Backed up to 300 for know your limits with 4,3 and 2 inch swingers. 4 and 3 inch were first round hits but the 2" took a couple of rounds to find it. Moved out to 400 again and then 500. Had a few rounds left so I brought it back to 100 to verify the 100 yard zero and set my turrets back to zero. Fired final 5 rounds at 100 and the last group was < 1".
All targets at 200-500 were steel and MOA or less.
I was extremely happy with the rifles initial performance. The ballistics were almost exactly the same as my 308 bolt gun with 175 grain Sierra Match Kings.
I was also impressed with the slick side upper receiver. Normally AR's throw brass a mile away unless you regulate the gas. I have had poor luck with adjustable gas blocks so I don't use them. I use a suppressor most of the time and run a heavy buffer. It's full gas. I shoot prone and when done, all the brass was piled up by my right knee in a spot about as big around as a 5 gallon bucket. Found every piece right there. No looking for brass!!!!!
I've built many AR's but this one is most impressive. I normally reload for distance but I think I'm going to be happy with the factory ammo for now. Ready to test terminal ballistics on some pork. Suppressor will be on next time.
Took to the range yesterday to functional check. Didn't take chrono. Used 123 grain Hornady Amax factory ammo. Fired about 20 rounds fouling and getting a good zero. 100 yard zero had quite a few fliers due to breaking in. Finally after 25-30 it came in pretty well. <1 MOA at 100. Was really happy with the results but was curious what it was going to do out at distance. Used the velocity printed on the ammo box, 2580 and figured it was with 24" barrel 1:8.5 twist. Since mine is 18" and 1:7.75 I used 2550 fps for my velocity. Used my JBM ballistic calculator and entered the guessed info.
The ballistic calculator said come up .5 mil for 200 yards. Dialed it in and had a first round hit. Fired a few at 200. Checked the iPhone for 300 and dialed the scope for it. First round hit. Did the same for 400. Second round hit. Same program for 500 yards. 4 rounds to hit 500. 1 of those 4 was a hit on the target stand. Got dialed in good and shot swingers at 400 and 500. Backed up to 300 for know your limits with 4,3 and 2 inch swingers. 4 and 3 inch were first round hits but the 2" took a couple of rounds to find it. Moved out to 400 again and then 500. Had a few rounds left so I brought it back to 100 to verify the 100 yard zero and set my turrets back to zero. Fired final 5 rounds at 100 and the last group was < 1".
All targets at 200-500 were steel and MOA or less.
I was extremely happy with the rifles initial performance. The ballistics were almost exactly the same as my 308 bolt gun with 175 grain Sierra Match Kings.
I was also impressed with the slick side upper receiver. Normally AR's throw brass a mile away unless you regulate the gas. I have had poor luck with adjustable gas blocks so I don't use them. I use a suppressor most of the time and run a heavy buffer. It's full gas. I shoot prone and when done, all the brass was piled up by my right knee in a spot about as big around as a 5 gallon bucket. Found every piece right there. No looking for brass!!!!!
I've built many AR's but this one is most impressive. I normally reload for distance but I think I'm going to be happy with the factory ammo for now. Ready to test terminal ballistics on some pork. Suppressor will be on next time.