Originally Posted by BADRACR1 (Post 1652699)

Twist ration is important. The lighter grain shells use a tighter twist to increase spin in order to make them more accurate. A heavier grain is likely to break apart at higher rate twists, hence the 1:7 and 1:8. Mine (Ruger AR556) is designed to use 62 grain, 1:8 twist. I use 55g a lot and at fifty yards not much difference. At a hundred the 55g will rise a little more due to the lighter weight. I would guess it would be more accurate with a 1:9 on the 55g. Faster spin, more level flight.

I also have one of the .22 Ar's (S&W M&P). Same with it. 1:15 twist on it. The 40g works best versus the 36/38/42.

BTW, the Ruger can be bought new for $549. Sometimes a little less. Grabagun ran them a few months ago for $519. That's a complete rifle with flip up sights and a warranty. I've had a bunch of custom builts (actually one with a Palmetto lower) and factory rifles. Sold off all but the Rugers after I bought the first one.

Originally Posted by Nox (Post 1652701)

For practical accuracy, 1:7 twist is fine. The military uses 1:7 for their M4’s and they shoot M193 (55 grain) rounds all day long.

Originally Posted by SnikPlosskin (Post 1652724)

Now it’s chrome vs. Nitrite :confused5:

Originally Posted by Nox (Post 1652726)

If you plan to shoot it and not clean it, and generally abuse it, get chrome lined. They are slightly less accurate, but they are easier to clean and stand up better to rough use. Military barrels are chrome lined. They may not be dead nuts accurate, but they get the job done.

Originally Posted by SQUIRMIN VERMIN 84 (Post 1652819)

Back in 1983 I bought a complete new G.I. parts set (minus the lower receiver),
and built my first AR. I got a PWA lower for 59 bucks.
It shot well but I've tried other uppers and Palmetto was great!

But I never liked the idea of blowing hot gas and burned powder into the
receiver so last month I picked up a new Adams Arms upper with 16"
barrel.
I also put a PDQ Ambidextrous bolt stop/release in because the stock
release is left handed.
Adams upper has no gas tube to the bolt, it's a gas piston-driven op-rod
and the receiver runs cooler and much cleaner. Same idea as M1's and M14's/M1-A's.
Added flip up sights. This thing is very accurate for the shorter barrel!

I love the modular platform of the AR series! SO versatile!!!

Originally Posted by Cybercowboy (Post 1652985)

NOW I WISH I GOT ONE OF THE ADAMS UPPERS YOU MAKE ME MAD!:lol:

Originally Posted by SnikPlosskin (Post 1653111)

Bought a Palmetto 1:7 Nitrite 16” with BCG for $199 on sale ($299 regular price). I’m going to play with this one. I’ve only field stripped. I want to understand how the stock comes off, how the gas tube goes in and out, etc.

Originally Posted by Nox (Post 1653183)

Some recommendations I have. Make sure you have a good set of punches and an armorer’s wrench. Trust me when I say a decent AR wrench will save you a lot of anguish and possibly damaged parts. Another recommendation is to work in a well lit location with a smooth surface. I do not recommend working on ARs in a carpeted area. Little things like detent springs love to hide in carpet.

Originally Posted by Nox (Post 1653183)

Some recommendations I have. Make sure you have a good set of punches and an armorer’s wrench. Trust me when I say a decent AR wrench will save you a lot of anguish and possibly damaged parts. Another recommendation is to work in a well lit location with a smooth surface. I do not recommend working on ARs in a carpeted area. Little things like detent springs love to hide in carpet.

Originally Posted by markids77 (Post 1653211)

Spring for a quality set of punches like the Starrets I use. Get extra long punches as standard length tools can be just a wee bit short to completely clear stubborn pins from your receiver without bottoming out and making divots around your pin holes because you will not think JUST THAT EXTRA TAP to make sure it really is bottomed will phuck up the surface of the receiver.

Originally Posted by SQUIRMIN VERMIN 84 (Post 1653228)

Starrets are good!
I've ground down the side of a couple of long punches to fit the landscape of the
receiver and lower the longitudinal center of the punch to match the center
of the roll pin I'm working with. Much better angle of attack and less prone to
slip off.

Originally Posted by markids77 (Post 1653292)

I have modded a dedicated roll pin punch to get at that pesky rascal that holds the bolt stop. I ruined a couple roll pins and scarred my first receiver badly before I got smart.