Whats causing these groups?

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I'm having trouble getting good groups from my AR. 20'' Bushy national match upper. Any suggestions? 40g v-max actually groups better than 52 or 55 grain. 1-9 twist.
shots.jpg
shot.jpg
 
Ok It was about 50 degrees with some wind. Shooting off of a Zero Kick rest. I started out a little over 24g and up to i think 27.5 with these 2 being the best. The other groups dont show 2 or 3 touching like that, they're scattered some. These are 5 shot groups.
 
Look as if you have two distinct groups within the group. That is evident in both groups.

So my question are you double tapping or are these individual shots with a
concerted effort to get back on the target dot.

If you can manage to get the subgroups together, then the whole group would be good.

Have you played with the amount of powder to see if that helps? Are you crimping?
What dies are you using? Lots of question?

Jimmy K

You answered some of the questions while I was posting.
 
I used Hornady fl sizing die and do not crimp and seat with a Lee dead length seater die. I tried to take about the same amount of time between shots. Maybe 15 secs pretty sure the cross hairs were in the middle of the red dot. Dot is 1/4" or so. Yes i played with the amounts of powder. If its cold out and the barrel isnt heating, do i still need to wait longer between shots?


3/8'' on dot size
 
What trigger do you have in your AR? Every AR I have ever shot with factory triggers, were horrible to hold a 5 shot group. I've since went with JP triggers and have really improved. My latest AR 10 came with 6 3/4 lbs of trigger pull. At 3 lbs, it's the difference between night and day.
 
I don't shoot an AR, and have very little experience loading for semi-auto rifles. It's very possible that groups like those are related to your firearm.

In my bolt gun that group would lead to me messing with my to C.O.L. This may be a limited option for you though as a longer C.O.L. may not fit in your magazine or feed correctly.

One other thing you might try is crimping with a Lee Factory Crimp Die. That eliminated some of this type of group variation in my rifle.

Have you done a good load development for this gun? Systematically tuning your reloads is the only way to get the most accurate ammunition.
 
What trigger do you have in your AR? Every AR I have ever shot with factory triggers, were horrible to hold a 5 shot group. I've since went with JP triggers and have really improved. My latest AR 10 came with 6 3/4 lbs of trigger pull. At 3 lbs, it's the difference between night and day.
My trigger was done by Bill Springfield. About 3.5 lbs
 
I've been loading them to 2.350. I guess i could try shorter. I did try some lightly crimping with the lee fcd. Really couldnt tell any difference.
 
If you're shooting the rifle with it resting atop a rest on a bench, those groups may well be normal. Horizontal stringing is common with most folks when they shoot holding their rifles atop a bench. Especially when they don't hold them very tight.

Try slinging up in a good prone position with the fore end resting on something firm and soft, then try it again. You may be surprised.
 
Farmer
I'm quite new to the AR rifle and I am working with my first AR, a DPMS Sweet 16 Bull barrel. That being said, I believe that it must be something to do with the ammo.

Are you getting consistent OAL, by that I mean not really tip to base, but some point on the ogive of the bullet to the base. I have found that the tip measurement will only give you what fits in the magazine. The bullet comparator in the photo below is what I use.

I have no idea about the Lee Dead length die, maybe someone with experience with it will come along.

Sounds like your shooting method is ok, may want to give yourself a little more time. I find that if I take a deep breath, exhale about 3/4 of it, hold then make my shot. I do this between each shot. If I'm shooting for a group, I give myself plenty of time. Whats the rush.

The trigger could very well be a big part of it. It took from 75 to 100 shots before I got the feel for my DPMS trigger. Yes I would like to replace it, but I don't have the funds right now.

http://www.sinclairintl.com/product/5581/Bullet-Comparators


Jimmy K

Sorry about the post lag ... phone calls...
 
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I've checked reloads with the Hornady tool that measures fom the ogive and was impressed with the consistancy the leed die seats. I didnt check these with it though.
 
What kind of scope?

Severe scope parallax could conceivably cause two groups in one group like that if you aren't getting your eye in the same exact place behind it every shot.

Suggest you get benched firmly on the target dot, and without moving the rifle, move your head from side to side & up & down and see if the cross-hairs move on the target.

rc
 
A 3/8" dot, in the wind, and you wonder what is wrong? Probably nothing.

Bart is right about shooting from a rest. It is different than shooting without one and takes some learning. It is very easy to push/pull/etc shots from a rest. Everything must be exactly the same each time.

It is very hard to teach shooting over the web. I stay out of most of these discussions for that very reason.

Get some books on shooting for accuracy from a rest. Go to a local match where they shoot matches.

Not trying to be a pain. It just is what it is. There are folks all over who can teach you. Find one at a range near you. :)
 
1-9" twist? My 1-9 twist HATES anything lighter than 62gr bullets. If I shoot 55gr or lighter bullets, I get horrible groups. It is a 16" barrrel.

It looks like you have one shot that is keyholed. I would try some 62,69 and 75 gr bullets in your reloads and see if that won't tighten your groups.
madd0c
 
A 3/8" dot, in the wind, and you wonder what is wrong? Probably nothing.

Bart is right about shooting from a rest. It is different than shooting without one and takes some learning. It is very easy to push/pull/etc shots from a rest. Everything must be exactly the same each time.

It is very hard to teach shooting over the web. I stay out of most of these discussions for that very reason.

Get some books on shooting for accuracy from a rest. Go to a local match where they shoot
matches. fortygrain.jpg

Not trying to be a pain. It just is what it is. There are folks all over who can teach you. Find one at a range near you. :)
But, here is forty gr v-max just a few minutes ago hiding behind a tree row with 40+ winds shooting out of the pickup window! 5 shots but only 85 or so yards. Pickup was rocking a little but managed to get shots off. I tried some 52gr now too but they didnt group well at all.
I have never seen a range let alone shoot at one. Nothing close here that i know of.
 
What kind of scope?

Severe scope parallax could conceivably cause two groups in one group like that if you aren't getting your eye in the same exact place behind it every shot.

Suggest you get benched firmly on the target dot, and without moving the rifle, move your head from side to side & up & down and see if the cross-hairs move on the target.

rc
I was hoping you wouldnt ask about the scope but its a Simmons i took off of my Ruger varmit 22-250 and has always held zero. Its 1 year old. 6x20 Everything else i use are Nikons Monarch and Buckmaster. I will check it as you suggested RC. Thanks
 
1-9" twist? My 1-9 twist HATES anything lighter than 62gr bullets. If I shoot 55gr or lighter bullets, I get horrible groups. It is a 16" barrrel.

It looks like you have one shot that is keyholed. I would try some 62,69 and 75 gr bullets in your reloads and see if that won't tighten your groups.
madd0c
I think the paper folded over is playing tricks on you. There are 5 shots there.
 
5 shots out of a rocking truck with 40+ winds that could almost be covered by a dime?

Wow. You should be giving us tips. :)
 
Normal groups from AR's. When the American Rifleman lists there tests for many different AR's in 223, 1 1/8" is about the average for 5 X five shot groups @ 100 yds. 25 shot total. But then internet groups are always much smaller.
 
5 shots out of a rocking truck with 40+ winds that could almost be covered by a dime?

Wow. You should be giving us tips. :)
Maybe the wind helped me. Never know. lol Those were the 40 grainers now, its the 52's i'm having trouble with. Just checked the weather info and we had gusts up to 43mph. Most of my shooting is out the pickup window. Those little p-dogs usually have to be hiding most of their body or be quite a distance from me or they're gone!
 
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