Best Bullet Weight for 1:7 Twist?

[markm]

I’d like to start reloading for those times I want some real accuracy.

77 gr OTM

[T2C]

I am getting much better results with AR-Comp and CFE-223 with 55g Hornday.

I am hovering right around an inch at 100 yds with a Wylde chamber w/1:8.

With a mil-spec 1:7 barrel and 77 SMK using RL-15, under 1/4 inch at 100 yds, using a fixed x10 scope.

My match rifle had a 1:8 twist barrel with a Wylde chamber and the same 55g Hornady reload I shot with the carbine grouped well under one inch at 100 yards.

I agree. The 77g SMK grouped really well in the father in law's 1:7 Colt HBAR. The Hornady 55g bullet with the right powder shot respectable groups as well.

[Tigereye]

77 gr OTM

This and XBR are a good combo.
I load 55gr Hornady FMJ with TAC and it's plenty accurate for me. All of my rifles are 1:7 twist.

[fedupflyer]

I have not tried the CFE rifle powder yet. Does the powder burn clean? Are there any pressure signs indicated on the brass?

No pressure signs and as far as I can tell it burns clean.
If you don't already have, pick up a copy of the Hornday reloading manual. For .223 and 5.56, their max powder loads seem to be "spot on" for accuracy. You may have to play with the seating depth a little to maximize the accuracy for your gun.

[user]

70 grain TSX works outstanding for me.

[Molon]

I’ve never loaded .223 before, but have decided to start loading some. I already have powder I can use from my .308 reloading and it is IMR 4895 and Varget. I have primers and dies on order. The rifle is a Colt 6920 that I’ve had for a few years. I have a ton of range ammo, but since I’ve put a scope on it and recently installed a Geissele SSA Trigger, I’d like to start reloading for those times I want some real accuracy. I’ll keep on buying cheap range ammo for plinking. I don’t plan to load large amounts, maybe 100 at a time.

What appeals to me so far, and I have not done much research on this yet, but 55 grain FMJ X-Treme bullets look tempting. 55 grain bullets are all I’ve shot with a few 62 grain M855's thrown into the mix. My groups at 100 yards with the scope at 4x are pathetic. I can do better with my .308 at 300 yards.

What bullet weight is popular for accuracy out of my 1:7 twist 16-inch barrel?

Every Barrel Is A Law Unto Itself



It’s not so much a matter of bullet weight, as it is a matter of finding a quality bullet that your particular barrel “likes.” Typical 55 grain FMJ and 62 grain SS109/M855 clone bullets do not fall into the quality category.

Bullets ranging in weight from 50 grains to 85 grains can produce fine accuracy from a fast twist barrel. You will often see posts on the Internet where people claim that their fast twist barrels only shoot accurately with the “heavier” bullets, but when pressed for their actual data, it turns out that they are comparing the heavy match-grade bullets such as the Sierra MatchKings, to garbage 55 and 62 grain FMJ bullets

Your Colt 6920 barrel is a chrome-lined, NATO chambered barrel with a government profile. Contrary to the nonsense that you will read on the Internet, this barrel will never produce consistent MOA precision. You can however greatly improve on your “pathetic” groups at 100 yards by finding a quality bullet that your barrel likes and tuning a hand-load for it.

A very small list of bullets that have produced fine accuracy from my semi-automatic AR-15s with fast twist barrels includes the following:

• Hornady 50 grain V-MAX
  
  
• Sierra 50 grain BlitzKing
  
  
• Sierra 52 grain MatchKing
  
  
• Hornady 53 grain V-MAX
  
  
• Sierra 55 grain BlitzKing
  
  
• Hornady 60 grain V-MAX
  
  
• Berger 62 grain HP
  
  
• Sierra 69 grain MatchKing
  
  
• Hornady 75 grain OTM
  
  
• Nosler 77 grain OTM
  
  
• Sierra 77 grain MatchKing
  
  
• Barnes 85 grain OTM
  
  

One of my standard hand-loads topped with the Sierra 55 grain BlitzKing has produced ½ MOA 10-shot groups at 100 yards when fired from my Krieger barreled AR-15s.











When fired off the bench from a free-floated Colt 6920 barrel, the 55 grain BlitzKing load turned in a 10-shot group at 100 yards that had an extreme spread of 1.3”. You’re not going to see any consistently significantly better precision than that from a stock Colt 6920 barrel.








....

[T2C]

"Every Barrel Is A Law Unto Itself" - MOLON

Terrific statement. It's true, very true.

[markm]

"Every Barrel Is A Law Unto Itself" - MOLON

Terrific statement. It's true, very true.

Be that as it may... if a barrel won't shoot 77 gr OTMs well...??? It's garbage.

[T2C]

Be that as it may... if a barrel won't shoot 77 gr OTMs well...??? It's garbage.

If a barrel will not shoot OEM Hornady 55g V-Max well, something is wrong with the rifle.

[Kansaswoodguy]

As long as the barrel twist is 1-9 or faster with the powders you listed both being rather slow for 223. Go with heavy bullets

Try 75gr bthp match hornady or 77 Seirra's bullets on top of 22.3gr IMR 4895 give or take a couple tenths dial it in for your rifle

With the same bullets I've had ok luck with 21.9gr of Varget

When or if you try lighter bullets a diffrent faster burning powder will usually give better accuracy and speed I like IMR 3031 for 50-55gr bullets