03-13-2011, 03:12 AM
As the original posting was basically asking for accuracy tips if they are building a rifle, here is what I would do:
1. Insure that the face of the upper receiver where the barrel extension meets it is square.
2. Invest in one of the good barrels...it truly is worth the extra money. Trying to build an accurate rifle with a mediocre barrel is similar to building a sword with mediocre steel having a mediocre heat treat. It will fail to do what you want.
3. Make sure the gas block is bedded tight, and the gas tube extension mates up properly with the bolt carrier gas key.
4. Use a free float tube.
5. Install a really good trigger.
6. Make sure that any muzzle devices are mounted square to the bore, not just to the outside of the barrel. Insure there is adequate clearance for the bullet to pass through the muzzle device, but not so much that it negates the device's purpose.
7. Insure that you have proper cheek weld when using the sights, and that the stock fits you properly. If either of these is off, your accuracy will suffer far more than you think it would. If you don't believe me, try shooting decent groups with your scope .25 of an inch too high, or too low...or with a stock that is 1 inch too long or too short.
8. Insure that when testing for accuracy, you aren't having a bad day. Be strong enough to admit it when you are having an off day, and come back when you can do better. It is far better than frustrating yourself, and blaming the rifle.
9. Use good ammo. If your reloads have more than .0025 runout, your groups will really suffer. .0015 and less is much better. Pay attention to your reloading technique, keep copious notes on what you use, and how it works.
10. Practice.
11. If you can afford one of the stiffer upper/lower receivers, stiffer is better, but not so much that it would be the first thing on my list. Barrel, trigger, ammo, fit of rifle are my top ones.
12. If your upper and lower have play when the push pins are inserted, try using a quarter inch shoulder bolt to replace the front pivot pin. If you get the correct length precision ground shoulder bolt, when you tighten it up, it completely eliminates play between the upper and lower receiver. The bolt, washer, and a nice brass acorn nut costs about $3.00 at most large hardware stores. I thought about marketing these, but decided AR people get hosed enough on accessories that are called "tactical". Buy one yourself, so I don't wind up buying them wholesale for $1.00 each, parkerizing them, call them tactical and sell them for $5.00 each, plus $3.00 shipping and handling...there is already enough of that.
1. Insure that the face of the upper receiver where the barrel extension meets it is square.
2. Invest in one of the good barrels...it truly is worth the extra money. Trying to build an accurate rifle with a mediocre barrel is similar to building a sword with mediocre steel having a mediocre heat treat. It will fail to do what you want.
3. Make sure the gas block is bedded tight, and the gas tube extension mates up properly with the bolt carrier gas key.
4. Use a free float tube.
5. Install a really good trigger.
6. Make sure that any muzzle devices are mounted square to the bore, not just to the outside of the barrel. Insure there is adequate clearance for the bullet to pass through the muzzle device, but not so much that it negates the device's purpose.
7. Insure that you have proper cheek weld when using the sights, and that the stock fits you properly. If either of these is off, your accuracy will suffer far more than you think it would. If you don't believe me, try shooting decent groups with your scope .25 of an inch too high, or too low...or with a stock that is 1 inch too long or too short.
8. Insure that when testing for accuracy, you aren't having a bad day. Be strong enough to admit it when you are having an off day, and come back when you can do better. It is far better than frustrating yourself, and blaming the rifle.
9. Use good ammo. If your reloads have more than .0025 runout, your groups will really suffer. .0015 and less is much better. Pay attention to your reloading technique, keep copious notes on what you use, and how it works.
10. Practice.
11. If you can afford one of the stiffer upper/lower receivers, stiffer is better, but not so much that it would be the first thing on my list. Barrel, trigger, ammo, fit of rifle are my top ones.
12. If your upper and lower have play when the push pins are inserted, try using a quarter inch shoulder bolt to replace the front pivot pin. If you get the correct length precision ground shoulder bolt, when you tighten it up, it completely eliminates play between the upper and lower receiver. The bolt, washer, and a nice brass acorn nut costs about $3.00 at most large hardware stores. I thought about marketing these, but decided AR people get hosed enough on accessories that are called "tactical". Buy one yourself, so I don't wind up buying them wholesale for $1.00 each, parkerizing them, call them tactical and sell them for $5.00 each, plus $3.00 shipping and handling...there is already enough of that.