loading for 1:7 short barrel

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jetech

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I need help from more experienced shooters, I am having trouble getting .223 55 grain bullets to group well in my 1:7 twist 16 inch barrel.

I have tried H335 and Varget at various loads and seating but I can't seem to pull the group in under 7" to 8'' at 100 yards.
62 to 69 grain bullets do better but I am hoping to tighten their groups also.

The rifle is a IWI Tavor chambered for 5.56/.223. I am using an EOTech sight with a 3x multiplier and shooting with a bipod.

I am thinking that a scope may help some over the red dot. What do you think?

Is there a powder better suited for the 16" barrel that I should try? Anyone have a good load that works for them out of a short barrel?

Thanks in advance
 
H335 shoots well in .223.

7" to 8" is pretty poor performance and it isn't the powder or the barrel length.

Bad barrel? Loose optic? Magnifier bad?


Mount a known good scope in quality rings/mounts and see what it is really doing?

Even poor bullets should do better than that.
 
I never could get my 1:8 Wydle chamber to shoot light bullets. H335 only gave me 3-4" groups. Tac was the best at 1.5-2". I tried like 7 different powders and 5 different bullets no go in my gun. It would shoot 65-69 gr < 1" using Varget.

Optics are going to be better than any dot sight. Dots are good for quickly getting on target but normally are 3-4" at best for accuracy. Make sure every thing is tight. Also if you have a quick adj stock they hinder accuracy too. The stock needs to be solid to get the best consistency.
 
I agree with others. I don't think it is the powder.
Inspect everything else including the chamber job.
Also take the muzzle brake off if you have one.
It is very rare but if the barrel was not dialed from the bore or something else wiht the chamber
might have some run out or short tenon or something else might be going on.
Make sure nothing is loose.
It is hard to tell via forum. Several things can be a factor.
 
The tavor has a low round count (~300). I don't think the barrel is bad but I don't know for sure.
I have gotten better groups with the heavier bullets (~3" to 6"). I believe the IDF shoots 55 grain bullets through the Tavor.
I am starting to suspect the optic. The magnifier isn't an expensive one and it didn't seem to help the grouping. The stock is a solid one piece.
I may try just the built in sights and see if that makes a difference.
 
I would try a fast powder, something like AA2015, Benchmark or RL10. Your H335 is probably still burning when the bullet runs out of barrel.

kwg
 
I would try a fast powder, something like AA2015, Benchmark or RL10. Your H335 is probably still burning when the bullet runs out of barrel.

kwg
I doubt H335 is "still burning" from a 16" but even if it were why would that produce such large groups. Like already said, it's not the powder or barrel length.

I'm also thinking the optics are at fault.

There is also an outside chance it's your 55gr bullet. While a 1:7" twist should shoot a 55gr bullet fairly well it's possible your bullet is very short and the fast twist rate is not playing well with your barrel. What bullet are you shooting? Name brand or bulk range bullets?
 
I am using RMR FMJ and Speer Varmint SP bullets in 55 grain.
 
I have numerous twist ratio barrels and I hate to say it but I have never gotten 55 grain FMJ bullets to group very well out of any of them. I only use them in a rifle that's got a red dot sight mounted because I'm not going to get better than about a 2.5" group out of anything. I made the mistake of buying 2,000 of them a while back without first trying them - in this case, "too good a deal to pass up" didn't really work out that well. As to your other thought, yes, I feel a scope with a fine reticle is always going to provide a better sight picture than any red dot around. That's just my opinion though. A Tavor isn't made to be a target rifle though - I would not be surprised to be limited to about 2" groups, but I don't have any experience with them either. I would try different bullet weights first. Good luck.
 
I don't know for sure what's going on. I have an AR style short barrel rifle but my twist rate is 1:9. The most accurate 55gr bullet I have found is the Sierra GameKing BTHP #1390. They are a little costly but very accurate for me in the above AR and even more so in my Howa 1500 .223 bolt rifle.
 
8 inch at 100 yards is pretty loose... Unless your bullets are shredding or keyholing I have to suspect the rifle or optic!

How good are the projectiles? Maybe an issue with the projectiles or loading practices?

My 1/7 twist will shoot the 60s and 55s just fine. Never tried really cooking them, but on normal loads no issues here.
 
I've a one in seven twist, thirty inch barrel. I have tried cooking Hornady fifty grain v-max and fifty-five grain super explosive soft point. As far up as I was willing to go, they stayed together. Groups and otherwise. The same loads held well in my AR. I only fired a few, even with the gas off I could tell it was a bit much for it.
Which leaves the shooter. Take no offense. Even an old Remington seven-sixty can make one inch groups. It just takes an immense amount of concentration, unique bench rests and a written journal of what didn't work last time. Also an objective look at the shooter. Seriously.

I like the Tavor, I've never shot one, but really do like them. I imagine that the same plan of attack would hold true for it as my thirty aught six.
With the way the rifle is assembled, how the shooter holds it, and the way the recoil moves through the system. There's a lot going on. And due to the design not much one can do about it.
Is the barrel free floated on one of these? Is the receiver tight to the chassis? How are you resting it?
How tight do you hold it? Do you place torque on it from the front to rear grips? Yes a finer scope would be much better.

It took a lot to get a pump action rifle to shoot well. I'm sure your Tavor can do it too. A premium bullet could help. Probably more than my questions. I wish you luck.
 
I am using an EOTech sight
EOTech has a huge recall going on for defective sights I do not know if it applys to yours or not but I believe its due to shifting point of aim ?
also how does it due with some factory match type ammo ?
 
I am staying within the manual guidelines for load data. The rifle does seem to perform better near the max load data. The bullets that I use are RMR, Hornady, Sierra and Nosler. Factory ammo performs the same.
The rifle is new to me and it is different to what I am familiar with so I haven't eliminated me as the problem. I am using a bipod shooting from a bench.
Not sure about a free floating barrel. It appears to be.
I am aware of the recall but have elected to keep the sight since the shift in moa is at extreme temperatures.
I will try to shoot today without the optics and see what happens.
 
I am staying within the manual guidelines for load data. The rifle does seem to perform better near the max load data. The bullets that I use are RMR, Hornady, Sierra and Nosler. Factory ammo performs the same.
The rifle is new to me and it is different to what I am familiar with so I haven't eliminated me as the problem. I am using a bipod shooting from a bench.
Not sure about a free floating barrel. It appears to be.
I am aware of the recall but have elected to keep the sight since the shift in moa is at extreme temperatures.
I will try to shoot today without the optics and see what happens.
Are you leaning into your bipod to reduce recoil bounce?
 
Lighter bullets are not going to group well from such a tight twist unless you slow them down. But 7" - 8" suggests something more serious is out of kilter. 1) see Horsey300 post above 2) see advice on optics above, 3) try heavier bullets to see whether twist/speed is an issue, 4) see Demi-human's post above. Best of luck.
 
"...a scope may help some over the red dot..." A scope will let you see the target better than a 2 or 3 MOA dot(that will entirely cover the black of a regular sighting in target at 100) but it will not make a rifle that doesn't shoot well do so.
55 grain bullets rarely work well with that fast a twist. Try some 70 plus grain bullets. Sierra makes an 80 grain Matchking that requires a fast twist. Ignore the velocities in manuals and on-line. They don't apply to a 16" barrel with a 1 in 7 twist. Ballistics by the Inch shows a bit under 3000 fps with 55 grain bullets with a 16" barrel. http://www.ballisticsbytheinch.com/223rifle.html
7" to 8'' at 100 yards is likely the rifle. Tavor triggers are know for being poor(11.5 lbs.) and the iron sights are too. The guys at Truth About Guns said the same thing. Best groups were 8" at 100. Called it a high priced range toy.
http://www.thetruthaboutguns.com/2013/06/foghorn/gun-review-iwi-tavor-sar/
 
I was able to shoot today. The wind was high and 90 deg to my range with strong gusts making it hard to stay on target. I decided to use the optics first so I slowed down and paid attention to making the shot. The first five were around 3". The remaining shot groups were 3" to 6" (it was hard to keep the dot on the target).
I noticed that my finger contact with the trigger was sometimes not correct. I believe the small pistol grip of the Tavor compared to the heavy stock of my M1A might be the reason. I think I am having a small issue transitioning to the pistol grip.

Turning the optic brightness down to where the outer ring was barely visible made the dot smaller and more precise.

I do pre-load the bipod and the trigger is a Geissele.
 
A bad day at the range beats a good day at work. But you did not have a bad day. As I read it you have cut your average group size in half or better. From seven to three. Perfectly acceptable for the type of rifle it is.
Well done.
 
Try using the bipod with a small rear sandbag. With my 16" AR, I use front and rear sandbags. I had similar problems using just the bipod even with a mid-level scope.
 
Thanks. I think it helped to turn the dot brightness down to where the outer circle was almost gone making the dot more pinpoint. I will have to try sandbags.
 
and with a red dot I would agree, not sure if you can do much better with that set up shooting moa or less would be a tough
task
I agree, I don't expect much better. I am hoping for more consistency or at least the same as an AR with the same barrel length if possible.
I miss the accuracy of my M1A but this rifle is a lot more fun to shoot.
 
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