I am looking at getting a Daniel Defense cold hammer forged 16" barrel for an AR-15 build I am doing now.

The barrel is a 1:7 twist. Will this fast of a twist shoot lighter bullets, 50 to 55 grain, ok?

I plan to shoot mostly 69 grain bullets (seems to be a popular weight for this caliber) but I have 500 55 grain bullets I just bought for another rifle, which I will probably sell to fund the AR build. Regardless, I just want a well-rounded barrel that will shoot, accurately many bullet weights.

I've shot 52 gn SMKs in a 7 twist without a problem. What ranges are you looking at shooting?

69's are okay 77's are a little better to 500 or 600. they'll make 750 or 800 if hard pressed but 80's do better past 600 out to 1K. 80's will be too long for magazine loading.

The purpose for the rifle is coyote/wolf hunting and rock chucks.

Realistically, I can usually call an animal in to less than 100 yards but it would be nice to be able to shoot out to 300.

I'm just not familiar with a 1:7 twist as most people I know shoot 1:9 or 1:8. The barrel is $295 so I don't want to regret the purchase if I have to shoot super heavy bullets. I've also been told some of the heavier bullets are unsafe to shoot in a semi-auto due to having to seat them so deep into the case to accommodate the magazine length.

All the BS about twist is just that. A 7 twist isn't going to make the lighter bullets shoot terrible. I have a COLT HBAR with the 7 twist and the rifle is phenomenal with all weights of bullets. I've had great success with the 69 grain Sierra hollow points. Now with that said you can buy a better barrel for around that same price from quite a few places...Lothar Walther to name one. Now the only thing with the big crazy panic buying going on is availability. If that DD barrel is available go for it. My personal choice for barrel length on the AR15 is 18 to 20. I don't need and inhibiting short barrel like the military. They choose it because they have to. It lacks the power for the longer distance shots and that's been pretty evident what is happening in Afghanistan.


Take a look at this chart of real shooting with actual rifles:

My AR a Sig M400 has a 1/7 twist on a 16.5" barrel in a 5.56 chamber.

I'm shooting 40g NBT out of it just fine. Also shot 55g FMJ stuff out of it with great accuracy .8-1.2" groups. I really don't plan on shooting the super long bullets out of that AR. I'm more of a advocate of the lighter bullets in that caliber, but every one is different.

If I were building an AR with mostly a varmint shooter I would be after a 1/9 and limit myself to 62g and under. Some recent studies have been made in a couple of Stab and Blast magazines that come to the same basic summary; 1/9 and 62 and less for bullet weight.

Handloader magazine has run some recent articles about stabilizing bullets and twist rates and a summary of the article was that generally you can't over stabilize a bullet with the twist rates that are out there. It might be possible to have some fragmentation with a 1/7 is you were shooting extremely fragile varmint bullets, but even then most bullets makers will tell you a rating for a particular bullet. I know that the NBT are unlimited as to velocity and twist rate and they are consider a varmint bullet in the .224 caliber.

quote:

It lacks the power for the longer distance shots and that's been pretty evident what is happening in Afghanistan.

I think you are full of crap... The 5.56 and its projectile was designed to wound, not kill, and you know it as well as I do. FMJs are not going to be lethal with a 30" barrel.

And as far as your chart of "shooting from real rifles", if the best I could do from all of those firearms was an average of 2 MOA, I would quit.

Thank you all for the input. I'm not in Afghanistan and I'm not shooting human targets Just looking to put some coyotes down.

Seems to me I should be ok with the 1:7 twist. It's not like I can be real picky right now anyway. I'm just trying to get an AR put together (w/out overpaying) just in case and if they don't bet banned then I can always change out parts later.

I looked at the 18" and 20" barrels. I was DEAD set on the 20" barrel until I picked one up that was mounted on an AR. WAY to long and too heavy for me. Plus, I won't be taking super long range shots. I believe the 16" will suit me just find.

quote:

quote:
It lacks the power for the longer distance shots and that's been pretty evident what is happening in Afghanistan.


I think you are full of crap... The 5.56 and its projectile was designed to wound, not kill, and you know it as well as I do. FMJs are not going to be lethal with a 30" barrel.

You're both right. With the 55 grain XM193 and 62 grain M855 FMJ stuff issued to the mainline troops, the combination of shorter barrels and longer ranges means those FMJ bullets don't have enough impact velocity to yaw and cause significant damage. Instead, they pencil through. So not only do they not wound effectively, the bad guy isn't even wounded badly enough to drop out of the fight immediately. Apparently, the rule of thumb was 3 hits would put the guy out of the fight. The 77 grain OTM Mk262 stuff issued to the spec ops guys was a whole nother deal.

With the faster 1:7 twist just stay away from bullets lighter than 40 grains and anything that's more explosive like Sierra Blitz and Hornady SPSX.

LWD

quote:

Originally posted by Doubless:

quote:

It lacks the power for the longer distance shots and that's been pretty evident what is happening in Afghanistan.

I think you are full of crap... The 5.56 and its projectile was designed to wound, not kill, and you know it as well as I do. FMJs are not going to be lethal with a 30" barrel.

And as far as your chart of "shooting from real rifles", if the best I could do from all of those firearms was an average of 2 MOA, I would quit.

I think you're a worthless piece of shit too!!!

doubless re-look at the chart.
the one rifle with the heavier bullets skewed the numbers by posting a 5" and a 26" groups size.
other than that the average would have been more like 1. sumthin.

the 7 twist will handle 55 gr bullets and even lighter no problem.
i have a stag 6-H and it will throw just about everything i have in groups well under an inch.
the faster twist can affect on game performance though.
with 50 gr spsx's a ground squirell will vaporize instead of merely becoming disjointed in several directions like with my 9 twist bbl's.
i haven't gotten to testing any cast in 7 twist yet but the 9 twist will shott them better than most think they will.
in fact littlegirl took second at the nevada shoot this year in both group and score with cast in her ar.
i know she would have done better on the group portion with a better scope.
she just dropped one x [last shot] which cost her the score portion [she had the group size by far at that point] which would have won the x score tie.

doubtless has a good handle...he's doubtless about guns and cartridges. Probably other knowledge too!

When you chop off the barrel on an M16 you lose lots of velocity. There's a huge difference between a 20 inch barrel and ones that are 16 and 14 inches.

Your hate for me blinds you dumbass.

Lamar, the pompous ass is on my ignore list so I won't go back and look at the chart. I called something he posted into question and he cussed me. I won't waste my time...

My point is this: yes, one rifle skewed the numbers, but there are a fair number of them if memory serves that are well above an inch.

My Stag 6H shoots bugholes too, and I have an 18" 6 X 45 that will put five shots into .3" at 100 yards. Repeatedly.

And the day that a 1 in 7 twist WON'T handle 55s and lighter will be a bad day...

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doubtless has a good handle...he's doubtless about guns and cartridges. Probably other knowledge too

No reading, no spelling dumb ass...

Nice to see a grown adult ruin a good thread.

I'm not a fan of 16 inch barrels but for 300 yards and closer the loss of velocity will not be much of an issue except at longer ranges. You will have to know your range tables for your load. Before someone takes that the wrong way I shoot from 100 to 1k so a 16 inch barrel doesn't cover that range. 20 inch match and bull barrels in an AR generally get a weight in the buttstock to balance the rifle again. When I get to my laptop later I'll see if I can estimate some drop tables.

There seem to be a couple of inconsistancies in the chart I'd attribute to the shooter and source. G&A? I'd like to see the targets but doubt they have them posted. The print experts expect to be taken at their word for their fidings and not look at who pays for advertising.

The purpose of the chart was really to show that the fast twists didn't and don't mess up the accuracy with the lighter bullets. Yes when it gets down to benchrest everything has to be chosen carefully including the twist, but we don't have that here in the op question.

I too have a 6x45 I built that shoots bug holes. It also will shoot less then 2 MOA at 350 with cast.

At least I don't send PM's and rag a person out and then close the topic and put on ignore to get a final say like doubless. Real big man of of you.

I see a reply from a certain individual; although I won't read it, I can guess what it says... so: for those of you who would like to do so, check out the title and intent of this thread. I think you might find something out about our esteemed poster that adds credibility to what I said.

http://forums.accuratereloadin...1811043/m/6851013081

Sam, if your post was aimed at me, I apologize. I simply stated my opinion, which I thought I was able to do on this site.

I won't post again in this thread. And again, my apology if my first post de-railed it.

quote:

Originally posted by Sam:
When I get to my laptop later I'll see if I can estimate some drop tables.

I would appreciate that. Thanks!

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Originally posted by DPollard:

quote:

Originally posted by Sam:
When I get to my laptop later I'll see if I can estimate some drop tables.

I would appreciate that. Thanks!

Go to this Hornady website and figure the ballistics out of any bullet, caliber, and velocity. It's very easy to use:

http://www.hornady.com/ballist...allistics-calculator

After looking at the 77 SMK at 2700 fps, my load velocity with a 20 inch barrel, and estimating 2500 fps for a 16 inch barrel. For muzzle energy at 2500 fps you lose about 85 yards.

If this pastes wrong I'll try something else.

It did, no tabs in columns.

EDIT TO ADD: PM sent with info. 5 inch drop difference at 400 yards and like I said 2700 fps muzzle energy is 85 uards closer. For varmints with a lighter bullet that probalbly changes considerably.

I'll figure out how to post it later if anyone care.

Doubless, your comment didn't bring anything to the DPollards question and attempted to portray the results SmokinJ posted as his poor shooing. SmokinJ didn't help himself much either. Opinions are welcome but I'm tired of seeing AR threads turn into dick size competitions. All they do is end threads and discourage participation. (Of course this is my opinion.)

Of the arguement you two are having the 5.56 was intended to cause wounding and even the SS109 is a crap anti personel round over 200 yards. The short M4 was meant as an entry weapon that is ill suited for field combat. Sadly the military always tries a one size fits all solution. We called it "Navy size too.", either too small or too big.

quote:

Originally posted by Sam:
Doubless, your comment didn't bring anything to the DPollards question and attempted to portray the results SmokinJ posted as his poor shooing. SmokinJ didn't help himself much either. Opinions are welcome but I'm tired of seeing AR threads turn into dick size competitions. All they do is end threads and discourage participation. (Of course this is my opinion.)

Of the arguement you two are having the 5.56 was intended to cause wounding and even the SS109 is a crap anti personel round over 200 yards. The short M4 was meant as an entry weapon that is ill suited for field combat. Sadly the military always tries a one size fits all solution. We called it "Navy size too.", either too small or too big.

Sam I couldn't agree with you more. My problem is that as soon as "twist" is mentioned a certain faction of folks go off the deep end quick about you can't do this or that with a 7 twist or you can't get any accuracy at all with fast twist. That boils me. Doubless is one of the ones in my cast threads on being no BS RPM threshold. They hate people that have shot accurate groups with cast at high velocity because they can't do it thus say it's not possible.

For anyone to say that our military deliberately designs and chooses a caliber just to would, not kill, another soldier is just plain crazy thinking. You're right about the M4 Sam. It was made for close quarters combat, room clearing, and getting in and out of vehicles easier. To ask it to shoot 300 to 400 yards or more and penetrate winter clothing and magazine belts that the enemy is wearing is just asking too much of the 5.56 cartridge.

I apologize to those not involved in the heated debate I was in with we know who.

Bottom line is a 7 twist will just be fine with just about all bullets and more to your advantage with the heavier bullets (more correctly put "longer bullets").