Best ammo for 1:7 twist rate barrels in 5.56 or 223 caliber

Coyotehunter_

Coyotehunter_

New member
What type of ammo do you use in your AR15's. I have a 18" long Cold Hammer Forged barrel with a 1:7 twist rate and am trying many different types of ammo in 223 or 5.56.

Right now I'm trying to shoot some of the Army Surplus M855 62 gr green tip ammo in 5.56. I'm having trouble with many variables and my groups are not tight at all. They are all over the place at 200 yards.

I've tried some Winchester 75 Gr bullets, Hornady Match Grade 75 gr bullets, and of course a lot of Ammo in the 5.56 55 gr FMJ type bullets.

I'm thinking that maybe the heavier bullets will shoot more precisely once I get the optics sighted in properly and break out the lead sled again. Trying to shoot at 200 yards off a shooting bag is hit and miss and I'm not that steady of a shot. And I was using an EXPS3-4 EOTech the last couple of times out at the rifle range and having trouble adjusting the windage and elevation on this puppy. I've never had to adjust it so much in the past. But I'm thinking that temperature extremes while it was in storage have caused the zero to change and the windage and elevation controls to malfunction somehow. It took me forever the last time out and lots of ammo to finally start hitting the bulls eye again.
 
I've been told that the longer the projectile the more stabilization you'd get. So lighter weight bullets, because of the smaller size, will benefit some, but may also break apart shortly after leaving the barrel. I don't know this for a fact. Usually I shoot either 55gr fmjbt or Sierra 1390 or 1365 bullets. My ARs are in all twists (7, 8, 9) and my bolt actions are either 9 or 12.

As far as shooting off a lead sled...I have one and find it difficult to use for the sole fact that unless you're 100% on the target without any pressure on the rifle/sled you're going to be applying torque or pressure that will negatively effect your shot. I use a 6" or 9" bipod and a rear sand bag while prone.
 
M855 Green Tip has never been accused of being an accurate round. Not even close.

For a 7 twist gun, try MK262. This is the .mil load that uses a 77 grain Sierra Match King. Factory MK262 will group surprisingly good groups for factory ammo.
 
For factory ammunition in .223 I'd suggest Black Hills loaded with 60 VMax bullets. They shoot MOA or better in every AR15 that I have used them in. Unless you're shooting dedicated BR they are very adequate.
 
I shoot a 1/8 twist tikka Never had a bullet come apart except for a Sierra in 40 gr. "Discontinued bullet" I have a 22 in Barrel You should have a plethora of bullets at your hand. You will not have bullets come apart with a 40 gr Bullet. I use 60 Vmax in mine now. Never had probs with the 40's however. Good luck! It depends upon what you are shooting and what you are hunting, shot placement etc.
 
Originally Posted By: Coyotehunter_What type of ammo do you use in your AR15's. I have a 18" long Cold Hammer Forged barrel with a 1:7 twist rate and am trying many different types of ammo in 223 or 5.56.

Right now I'm trying to shoot some of the Army Surplus M855 62 gr green tip ammo in 5.56. I'm having trouble with many variables and my groups are not tight at all. They are all over the place at 200 yards.

I've tried some Winchester 75 Gr bullets, Hornady Match Grade 75 gr bullets, and of course a lot of Ammo in the 5.56 55 gr FMJ type bullets.

I'm thinking that maybe the heavier bullets will shoot more precisely once I get the optics sighted in properly and break out the lead sled again. Trying to shoot at 200 yards off a shooting bag is hit and miss and I'm not that steady of a shot. And I was using an EXPS3-4 EOTech the last couple of times out at the rifle range and having trouble adjusting the windage and elevation on this puppy. I've never had to adjust it so much in the past. But I'm thinking that temperature extremes while it was in storage have caused the zero to change and the windage and elevation controls to malfunction somehow. It took me forever the last time out and lots of ammo to finally start hitting the bulls eye again.

tight groups with a eotech at 200 yards with surplus M855 62gr ammo and a factory mass produced barrel is going to be tough for a good marksman. you say you are not that steady of a shot. going to be even tougher for you. sounds to me like maybe you are just chasing your bullet holes all around the paper with the dials on the ecotech. just a guess.
 
I'm with SlickerThanSnot. 200 yards, EOtech, and M855 isn't going to group well. M855 never grouped well for me even at 100. Definitely not accurate ammo as far as I'm concerned.
EOtechs aren't really made for precision shooting at 200 yards either.
Not to say it couldn't be done, of course.
 
Well things have changed somewhat. My last range trip after the above fiasco had the groups with the M855 back on track. I shot three times and all were within 2" of each other at 200 yard and one was right in the middle of the 2" diameter bulls eye.

I'm thinking that it was the EOTECH not the M855 rounds. This time at the range everything went perfect for me. I only had 30 minutes to shoot this trip. So I was only able to setup quickly and fire three rounds before the range closed down.

I drove home with a smile on my face.

I really need to get to the range much earlier and take more time to sort this out.

But I'm now thinking that my Ambush Firearms 1:7 18" long barrel likes these M855 rounds.

I still have to clean my AR15 as since I only fired three rounds I'm thinking that it's not that dirty. But the thought of leaving sulfur residue inside my barrel is making me want to clean it anyway. I don't like leaving gun power residue in there to attract moisture and corrosion when the gun is not being used. Its' been too cold and raining the last few days for me to get out and shoot again. This next Thursday it's suppose to warm back up in the mid 60's and then I may go out and shoot at the range again. Hopefully I'll have a lot more time.

I took the Lead sled to the range the last time and didn't get to use it. I shoot using the Caldwell Tack Driver shooting bag filled with cat litter. The lead sled stayed in the new roughneck plastic box that I purchased just for the lead sled to ride in the back of my pickup truck. I've got several of the different sized Rough Neck Plastic boxes with lids on them to carry my shooting supplies. I can leave these boxes in the garage and easily put them into the bed of the pickup truck when I'm ready to go shooting. I don't even take the boat out of the garage anymore since I'm busy shooting instead of fishing.
 
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Originally Posted By: millerjqI'm with SlickerThanSnot. 200 yards, EOtech, and M855 isn't going to group well. M855 never grouped well for me even at 100. Definitely not accurate ammo as far as I'm concerned.
EOtechs aren't really made for precision shooting at 200 yards either.
Not to say it couldn't be done, of course.

I'm using the 3x G33 EOTech flip to the slide quick attack Magnifier with the EXPS3-4 HWS from EOTech. The 1 MOA dot is only covering 2" at 200 yard and with the 3X magnification it's easier to shoot at longer ranges. With my lead sled holding the AR15 firmly when I shot the precision and accuracy of this guy system is much better than without the G33 magnifier.

I do agree that with just the EXPS3-4 the precision at 200 yard with any type of bullet will be poorer. The G33 magnifier can be adjusted for your eye sight with a diopter adjusting ring and the entire sight picture can be adjusted up/down or left/right with two other adjustment knobs on the G33 unit. This make the sight picture very clear. While it's only magnified by 3X that's a lot better than having no magnification at all.

For me the biggest problem is holding the AR15 still and pulling the trigger at the exact time that the 1 MOA top dot is lined up perfectly on the Bulls eye. I use the 17" large Shoot N C targets with the 2" diameter bulls eye and the 1 MOA EOTECH red dot covers the entire 2" bulls eye perfectly. But that also helps me aim in a way. A lager red dot would be harder to use which is why I'm glad that the EOTech company decided to use the 1 MOA dot instead of a larger one. The 65 MOA outer circle on the EOTEch's reticle system helps to get on target faster and then the smaller dots inside give you the increased resolution that's needed to be very accurate. As long as the EOTECH's Zero is not changing. And that is what I'm concerned with. One time after it sat for a year in the box without being used it changed the zero 4 moa. I readjusted the EOTech's zero and then a week or two later went back to the range and the zero was right on the money this last time at the range. I hope that the next range trip will be as the last. I'm more convinced now that any changes are coming from the EOTech's optics adjustment system and not the bullets or the gun that I'm shooting. Hopefully my next range trip will allow me more time shooting to help me sort this all out.
 
Originally Posted By: Coyotehunter As long as the EOTECH's Zero is not changing. And that is what I'm concerned with. One time after it sat for a year in the box without being used it changed the zero 4 moa. I readjusted the EOTech's zero and then a week or two later went back to the range and the zero was right on the money this last time at the range. I hope that the next range trip will be as the last. I'm more convinced now that any changes are coming from the EOTech's optics adjustment system and not the bullets or the gun that I'm shooting. Hopefully my next range trip will allow me more time shooting to help me sort this all out.


sometimes i think you do not read or do not understand some of the suggestions people give you to some of you problems you have. it has been said a couple of times that as you take that ecotech off the gun and put it back on that the zero very well could or will change. but you keep doing it. why do you take it on and off?

it is well known that the ammo you are shooting is not known as being accurate. and guys on here have told you that. why do you keep using it?
 
Because it's cheap, I'd guess. I use cheaper ammo just for fun on steel spinners and such.

But if I'm trying to get good groups and testing zero, it's usually hornady ammo for me.
 
I have been testing ammo on my 7 twist 20" YHM barrel for my AR and have tested everything I can get my hands on from 50-77 grains and the two best that I have found are 55grain hornady premiums with .75" groups at 100 yards and federal premium loads with 77grain smk's giving me .47" groups at 100 yards. I did all my testing before I installed my aftermarket CMC trigger so now I need to try it all again. most likely the 77 SMK's will still be the best, but I want to make sure before I start making up handloads. 1$/round is kinda spendy to be shooting prairie dogs and yotes with.
 
Savage Axis .223 1/9"
RRA Predator Pursuit 16" SS 1/8"
M4gery with 16" BHW 1/8"

25.5 grains of Benchmark
Federal AR Match primers
52 grain Hornady Match BTHP
>= 3/4" at 100 yds from all 3 rifles. I didn't chrono them but the load did not show signs of pressure out of any rifle.
 
Originally Posted By: millerjqI'm with SlickerThanSnot. 200 yards, EOtech, and M855 isn't going to group well. M855 never grouped well for me even at 100. Definitely not accurate ammo as far as I'm concerned.
EOtechs aren't really made for precision shooting at 200 yards either.
Not to say it couldn't be done, of course.
DIDO on the 855 junk its cheap machine gun ammo although ive found if I go out and move my target up tp 25 yards i can get pretty good groups LOL
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Originally Posted By: Goe BlowOriginally Posted By: millerjqI'm with SlickerThanSnot. 200 yards, EOtech, and M855 isn't going to group well. M855 never grouped well for me even at 100. Definitely not accurate ammo as far as I'm concerned.
EOtechs aren't really made for precision shooting at 200 yards either.
Not to say it couldn't be done, of course.
DIDO on the 855 junk its cheap machine gun ammo although ive found if I go out and move my target up tp 25 yards i can get pretty good groups LOL
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So that's how I can tighten my groups up. Why didn't I think of that before!
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Had a problem in my Ruger American predator not stabilizing 55gr. Switched to Australian Outback 69gr and solved to problem. In my predator at 100yds can put a hole in a hole as long as I don't twitch haha.
 
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