What Bullet wgt. for 1:8 twist AR-15?

Walk Softly... · August 09, 2003, 17:27

I'm getting ready to start reloading for my paper-killing AR, it has a 20" SS heavy barrel with 1:8 twist. What wgt and type of bullet will give me the best accuracy for 100-200 yds? I won't be shooting any further than 200 yds due to range limitations.

NoNotAgain · August 09, 2003, 19:52

Walk Softly

69 grain and up bullets will stabilize in an 1:8 twist barrel.

Check out the Sierra Match Kings in 69, 77, and 80 grain.

I use Reloder 15 for my .223/5.56 and 308/7.62 loads.

25 grains of Reloder 15 with the 69 grain Sierra yeilds about 2750fps in a 24" barrel.

Sgt_Gold · August 10, 2003, 18:12

A 1\8 barrel will stabilize anything up to 80 gr. The heavier bullets are better in the wind, but at 200 yards wind won't be much of a factor. Look into the lighter Sierra and Hornady bullets. I know some shooters using the 52 gr match king for reduced course matches.

55bird · August 10, 2003, 22:04

Dang Good Advice!

**Cava3r4** · August 17, 2003, 16:37

I have had a lot of success using 77 grain sierra match kings moly coated.
(REDUCE LOADS 10 PERCENT AND WORKUP!!!)
I use 77's on 200 offhand, 200 rapid sitting, and 300 prone rapid. That way I don't have to worry about "mixing them up" (69 grains and 77's). 80's you can tell at a glance.
I use 24.5 grains of varget, small winchester brand rifle primers, and have been using military brass.
On the 600 yard line I am using the 80 grain sierra match kings moly coated with the same load but in new winchester brass.
I've had good luck with Varget in my dillon 550. I also use varget in my .243 praire dog rifle and my 7.62 NATO.
I know some folks who use reloader 15 and vita vhitorri (sp?) successfully as well.
Works for me.
Have fun and good luck.
Bob

**W.E.G.** · August 17, 2003, 19:41

At distances of 200 yards and less, if you can't do it with a Sierra 69 MK, it can't be done. There are a lot of good bullets out there. The 69 MK will give you the versatility of having just one load for each course of fire.

No need to use hot loads for distances that short.

Sierra 69 MK's seem to like all powders. Usually 2.0 grains below the max load in the book will give you results that will make you dance.

If you start pushing toward max loads, you really need to test accuracy and standard deviation. Accuracy can go absolutely to hell when you start reaching the "ragged edge" with your load data. AMHIK.

If you want to venture into rounds that won't feed through the magazine, I've had good luck with the Sierra 80 grain MK's. Here is a 20-shot group at 100 yards (AR15 service rifle...iron sights...fired from prone, with military sling).

55bird · August 17, 2003, 20:46

Roger all that stuff!My very thoughts.

August 09, 2003, 17:27	#1
Walk Softly... Registered FALaholic #: 6061 Join Date: Apr 2002 Location: Parkersburg, WV Posts: 316	What Bullet wgt. for 1:8 twist AR-15? I'm getting ready to start reloading for my paper-killing AR, it has a 20" SS heavy barrel with 1:8 twist. What wgt and type of bullet will give me the best accuracy for 100-200 yds? I won't be shooting any further than 200 yds due to range limitations.

August 09, 2003, 19:52	#2
NoNotAgain Registered FALaholic #: 6893 Join Date: Jul 2002 Location: Peoples Republic of Maryland Posts: 1,341	Walk Softly 69 grain and up bullets will stabilize in an 1:8 twist barrel. Check out the Sierra Match Kings in 69, 77, and 80 grain. I use Reloder 15 for my .223/5.56 and 308/7.62 loads. 25 grains of Reloder 15 with the 69 grain Sierra yeilds about 2750fps in a 24" barrel. __________________ Without the Second Amendment to the Constitution, there is no first.

August 10, 2003, 22:04	#4
55bird Registered FALaholic #: 799 Join Date: Aug 2000 Location: Tampa,Fl,U.S.A. Posts: 1,041	Dang Good Advice! __________________ The very things my grade school teachers of the 1960's warned me about communism,my government is today:skull:

August 17, 2003, 19:41	#6
W.E.G. Administrator Silver Contributor FALaholic #: 1211 Join Date: Oct 2000 Location: Virginia Posts: 31,055	At distances of 200 yards and less, if you can't do it with a Sierra 69 MK, it can't be done. There are a lot of good bullets out there. The 69 MK will give you the versatility of having just one load for each course of fire. No need to use hot loads for distances that short. Sierra 69 MK's seem to like all powders. Usually 2.0 grains below the max load in the book will give you results that will make you dance. If you start pushing toward max loads, you really need to test accuracy and standard deviation. Accuracy can go absolutely to hell when you start reaching the "ragged edge" with your load data. AMHIK. If you want to venture into rounds that won't feed through the magazine, I've had good luck with the Sierra 80 grain MK's. Here is a 20-shot group at 100 yards (AR15 service rifle...iron sights...fired from prone, with military sling). __________________ . . . Ask me about the Mason-Dixon FAL Collectors Association.

August 17, 2003, 20:46	#7
55bird Registered FALaholic #: 799 Join Date: Aug 2000 Location: Tampa,Fl,U.S.A. Posts: 1,041	Roger all that stuff!My very thoughts. __________________ The very things my grade school teachers of the 1960's warned me about communism,my government is today:skull:

August 10, 2003, 18:12	#3
Sgt_Gold Registered FALaholic #: 6672 Join Date: Jun 2002 Location: Behind enemy lines Posts: 2,161	A 1\8 barrel will stabilize anything up to 80 gr. The heavier bullets are better in the wind, but at 200 yards wind won't be much of a factor. Look into the lighter Sierra and Hornady bullets. I know some shooters using the 52 gr match king for reduced course matches.

August 17, 2003, 16:37	#5
Cava3r4 Curio & Relic Silver Contributor FALaholic #: 6560 Join Date: May 2002 Location: AZ...originally from St. Paul, MN Posts: 4,297	I have had a lot of success using 77 grain sierra match kings moly coated. (REDUCE LOADS 10 PERCENT AND WORKUP!!!) I use 77's on 200 offhand, 200 rapid sitting, and 300 prone rapid. That way I don't have to worry about "mixing them up" (69 grains and 77's). 80's you can tell at a glance. I use 24.5 grains of varget, small winchester brand rifle primers, and have been using military brass. On the 600 yard line I am using the 80 grain sierra match kings moly coated with the same load but in new winchester brass. I've had good luck with Varget in my dillon 550. I also use varget in my .243 praire dog rifle and my 7.62 NATO. I know some folks who use reloader 15 and vita vhitorri (sp?) successfully as well. Works for me. Have fun and good luck. Bob

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