Post your updates on success with 68s, 69s, 70s, and 75s in a 1 in 9" twist


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Dr. Tad Hussein Winslow
March 25, 2010, 08:24 PM
please...

Let's hear what you got - who all shoots Hornady TAP 75s, etc., or anything in the 68-75 gr range in 5.56x45 with a 1 in 9 twist, with good accuracy? If so, what barrel length, and at what ranges?

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sscoyote
March 25, 2010, 08:44 PM
I've been using 69 SMK's, 65 SGK, and my favorite 65 JLK Low Drag on coyotes this year for longer ranges out of my ISSI (insightshootingsystemsinc.com) 223 AI upper--26" 9-twist Hart.
Here's the 60 (BC-.339) and 65 JLK's (BC-.395) either side of the 60 V-Max for comparison--
http://i157.photobucket.com/albums/t49/sscoyote1/IMG_0769.jpg

Here's the DPMS VLD magazine (now discontinued) with the 65 LD to "magazine" length--

http://i157.photobucket.com/albums/t49/sscoyote1/DPMSVLDmagazine.jpg

...and mommy and wifee shooting up all my ammo--

http://i157.photobucket.com/albums/t49/sscoyote1/IMG_0921.jpg

Dr. Tad Hussein Winslow
April 13, 2010, 11:29 AM
Awesome Steve! Thanks very much for the detail and the family pic!

I'm am assuming that very few other people have had success with the heaviers and 9 twists - anyone?

Mags
April 13, 2010, 11:36 AM
It is hit and miss with me, the Hornady Tap 75 grain HP shot fine in my Del Ton 16 inch 1-9 twist barrel at 100 yards, then Privi 75 grain match HP patterned like buckshot in a Bushmaster 14.5 inch 1-9 twist barrel. 69 grainers shoot well out of both barrels. I would like to add on the box of Hornady Tap it specifically said "for 1-9 twists or faster", I was skeptical of it's performance in a 1-9 barrel but it performed well.

jbech123
April 13, 2010, 11:50 AM
I have a savage LRPV with a 9 twist. It's a tackdriver with black hills 68 gr match. I've shot the wolf 75 gr match and it was aroun .75" at 100yds, so that shoots good as well. Next up is the 77 gr black hills.

Sediment
April 13, 2010, 12:15 PM
69 grain Sierra JBTHP from my AR-15 16" bbl, 1:9 twist. Shot from 25 yds standing position and I'm happy with it. My personal handload also, not an off the shelf box.

http://i341.photobucket.com/albums/o366/lagavulin9900/photo.jpg

JuryRig
April 13, 2010, 02:33 PM
Handloaded 69 gr Sierra Matchkings do 0.7 MOA in 1:9 twist 20 inch barrel. Haven't tried anything heavier yet.

M1key
April 13, 2010, 04:11 PM
LOL...25 yards?

Bushie 20 inch, 1:9, 70 Speer soft point handloads (22.5 gr 2015), .50 to .70 MOA

Mags
April 13, 2010, 04:51 PM
LOL...25 yards? Don't know much about ARs do you even though you have a Bushmaster? But you do like to make fun of others huh? ARs are battle sighted at 25 yards. Obviously you didn't know.

M1key
April 13, 2010, 05:27 PM
Chill out. No insult intended. The OP was inquiring about ACCURACY. Not much to be learned at 25 yards.

With a 20-inch barrel, zero @50 yards works better for me.

And no, the Bushie ain't all I own, sonny.

R.W.Dale
April 13, 2010, 05:40 PM
When I had a 1:9" savage 24" flv bb I was suprised at just how well 75g a-maxes shot.

I'll try to find documentation when I get home.

Sediment
April 13, 2010, 06:03 PM
My 25 yard range was the only place I went at the time to test out my revised formula for my handloads. I know it's not record breaking or anything and I'm fine with that. I have high powered rifles to reach far beyond that. OP was asking about accuracy with a weight of bullets and I happened to handload one of the weights.

Just though I would share.

P.S. The rifle is not scoped, I have an EOTech holographic with no magnification. If I can see it I can hit it, and that's just fine by me.

Dr. Tad Hussein Winslow
April 13, 2010, 06:46 PM
Not much to be learned at 25 yards.

Actually Mikey, the Real Mags is correct - you can most certainly learn a lot about accuracy at 25 yards, by the group size. You cannot learn as MUCH as you can at 100 or more, but you can learn a LOT. If you bullets all go into 1 hole at 25, then you know (a) you are good to go on combat distances, and (b) you're probably under 1 MOA at hunting distances. So it was a bit rude to scoff at the notion of learning what your rifle is capable of (to an extent) at 25 yards. If you get 2" or 3" groups at 25 yards, then Houston, we have a problem.

M1key
April 13, 2010, 07:17 PM
Dr. Tad,

Mea culpa. I was assuming you were looking for useful information, such as I provided. I have been shooting and handloading for ARs in various calibers for nearly 35 years. You don't test for accuracy by "standing and shooting at 25 yards" with an AR-15.

If you are utilizing good bench rest shooting skills and are getting 2-3 inch groups at 25 yards with an AR-15, there may be a serious problem with rifle, ammo, and/or shooter. You may do well to take up another sport.

And for Mr. Sediment, 16 inch barrels with 1:9 twist don't usually stabilize the heavier bullets (69gr+) as well as the lighter ones (45-63gr). You will find that out when you shoot out to 100 yards and further.

Out of my Colt Match Target (9x scope, 16 inch barrel, no wind), Sierra 52 match hp groups flirt with .50 MOA while 69 Sierras spread to .75-1.0 MOA.

When I switch to the previously mentioned 20 inch "Crapmaster", the same 69gr loads shrink down to a bit under .60 MOA...

Though as always, YMMV.

jpwilly
April 13, 2010, 11:19 PM
I have two AR's (DPMS) one is an M4gery with 16" bbl and the other 20" Bull barrel both with 1-9". So far I've only tested the heavier 68gr and 69gr stuff in the bull barrel upper and it has keyholed. Some 1-9" barrels will stabilize those but mine won't. I went back to 50-62gr pills and shooting 3/4"-.5" groups for the most part with a few 3/8" thrown in. The rifle is a solid 3/4" 5 shot group at 100yrds all day long using BL-C2 or Varget.

67rschev
April 14, 2010, 01:05 AM
Gave up on the 68 69 bthp match bullets in a Mini 581 model , 1 in 9 with 16 inch barrel . With 55 to 60 gr ballistic tips 5 shot groups will average moa , and with the 68 and 69 grainers its like a grim 2 1/2 . It wasn't key-holing , but it sure wasn't stable .

sneedb82
April 14, 2010, 01:24 AM
Hey Doc. Hadn't had a chance yet to test out the heavier stuff. However, my particular 1/9" twist barrel is a DPMS Sportical, and it doesn't like 55gr Vmax. It loves 62gr Brown Bear JHP.

I've got some 70gr and 72gr pills coming from SSA and Ammotogo to determine the likelihood of these being shot out of the DPMS.

The end of the summer however, or sooner, a new ML Spikes Tac upper will be tested to determine what it likes the best as well.

Oh, and for the original question: 62gr Brown Bear is .60MOA at 100. 55gr Vmax is 1.5MOA.... Food for thought.

Dr. Tad Hussein Winslow
April 14, 2010, 09:16 AM
You don't test for accuracy by "standing and shooting at 25 yards" with an AR-15.

OK, that's true - so you're both right! :D

Sediment
April 14, 2010, 11:36 AM
Just to appease the critics next time I hit the long range I'll take my AR-15 out to the 100 yard line and see if I can even hit the orange. Should be interesting enough with the new Savage and an AR with the regulars shaking their heads looking at me :D

dom1104
April 14, 2010, 11:44 AM
Uh, so is my 1/9 the only one that works with 77 grain hornady just fine at 100?

Or is it like flying ridonkulous at 105+ or something

I always just assumed all that that bullet length stuff was mostly academic, I bought a box of 77s, tried them out and they worked fine. at least as far as I could tell from a sandbag rest.

dom1104
April 14, 2010, 11:48 AM
Hey you know what just occored to me, I wonder if its possible my rifles twist rate may NOT be 1/9.

I mean, mistakes happen I imagine. huh.

Dr. Tad Hussein Winslow
April 14, 2010, 12:59 PM
Yep, mistakes do happen, and companys change twist rates sometimes. If you were toward the end of the old batch or toward the beginning of the new batch, it may be mis-marked!

jbech123
April 14, 2010, 01:50 PM
I always just assumed all that that bullet length stuff was mostly academic
You have to be sure to take into account variables like barrel length as well, but long heavy bullets do need faster twist. I too have shot up to 75gr in a 9 twist with good results, but keyholing is a very real concern, just a matter of exactly what a particular rifle will do. try 80 grain or heavier in a 16" 1/12 twist, I'm sur ethat would keyhole.

dom1104
April 14, 2010, 02:01 PM
Well it kinda went like this.


1. "Well, the people on the internet said this wouldnt work"
2. <loads up 16 inch M4 profile DSarms cheapo nitrided upper with 77 grain>
3. <bang bang> looks fine....
4. "Well those people on the internet are wrong."

So I kinda figured, it was something probably true, but overhyped.

But the possibility that my upper may in fact be 1/7 or possibly something goofy in the middle, 1 in 8.5, one in 6 lol.

In in 9 on the first 3 inches, one in 4 in the last 13 :)


I dunno, I am not going to overthink it I think I will just shoot the thing.

If you enjoyed reading about "Post your updates on success with 68s, 69s, 70s, and 75s in a 1 in 9" twist" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!