What barrel for .223 Wylde AR for 40-grain?? (Current rig unusable)

M

MagnusRex

New member
Hey all - LONG story short, I've got a 1:7 18" .223 Wylde PSA upper that I've been shooting 40-grainers out of. I like 40-grain because out to 225 yards POI is under 2..5" from the reticle! It's not a 6.5 but it's plenty flat enough for the type of hunting I do. And I've bought a bunch of it. I put this gun together for coyote only and I've shot it exclusively with a suppressor. After some frustrating and unexplainable misses, I've discovered that the cold-bore shot (which is often the only shot in hunting!) is hitting 10+ MOA low. I'm under no illusions of what to expect out of a PSA barrel on a gas gun, but this setup is pretty much useless like it is now.

In the very short-term I'm going to try to rezero without the suppressor and see if that brings the cold bore shot somewhere close enough that I can hunt for the rest of the season. Long-term, I've read everything I can find and it generally seems that the higher quality the barrel, the less cold-bore shift there should be, so I'm hopeful that a new barrel (probably thicker too) might fix my problem. Before today I barely understood the relationship between barrel twist and bullet weight, but seems like this 1:7 barrel is likely the very worst option for 40-grainers, and may even be part of my ridiculous cold-bore shift.

So - I'd like to get this rifle shooting Minute Of Coyote (2-3 MOA is plenty) without spending a silly amount of money upgrading a PSA. Do you all think a new barrel would be a logical first step? If so, what barrel would work with my nice flat 40-grainers? Seems like the mythical 1:12 twist may be best for 40-gr., but I haven't found any AR barrels in that, never mind 18" .223 Wylde. I know I'm far from the only one shooting 40-grain or thereabouts from an AR - what do you all find works well?

Sorry for the convoluted explanation - this issue has been giving me fits and I'm very grateful for your wisdom and input!
 
I have a 1:7 18" PSA that groups better with 40-55gr bullets than it does with 62-77gr. Who knows why?

I started using the 55gr Norma Tip Strike and it shoots them well enough that I can heart punch a coyote at 200 yards. So that's good enough for me.

That much of a shift is crazy. Let us know what you find out.
 
i have a 1:8 twist wilson combat 20 inch super sniper barrel in 223 wylde. that shoots the 53 grain v-max like a laser, 1/2 groups at 200 yards if i do my part. cold bore shots are dead on too.

they recommend a 1:9 twist for 40 grain bullets (not much help, sorry about that)

Twist Rate Information​


  • .223 Remington/5.56mm NATO

    1-7: Match or hunting bullets in the 68gr – 80gr range

    1-8: Match or hunting bullets in the 50gr – 77gr range (best all around choice)

    1-9: Match or hunting bullets in the 45gr – 69gr range
 
Man, that's the worst cold bore shot I've ever heard of.

The first place I'd look would probably be a powder change.

Otherwise, for a barrel recommendation, last year I built a new upper with an X-Caliber barrel in a 12" twist with a 223 Rem chamber, not Wylde, as I wanted to shoot 52/53 grain bullets only for night time coyotes. The Rem chamber has a shorter .025" freebore, so you get the bullets close to the lands & still fit in the mags. Mine's an honest half MOA shooter, & am more than pleased with this barrel.
 
I've had barrels very occasionally throw the first shot 2 or 3 inches, but never 10+. I would think you could pick up anything from a bargain bin ar stoner on up to top of the line and be better than that. For 40's if you're custom ordering a 12 twist would be plenty but off the rack you're going to be lucky to find a 9 and 8 is more likely.
 
Sounds like you’ve got a new tomato stake for the spring.
For 40’s 1:12 or possibly 1:14, but either will likely be a custom order.
Criterion may have something. Like the others have said 1:8 or 1:9 will likely be what you will find available.
I have a Ballistic Advantage 1:9 223 Wilde upper and it’s excellent with factory 55gr Vmax ammo. I haven’t tried anything lighter than that since it shoots so well. My tikka has a 1:8 and also is excellent with the 55.
Either way I’d def be getting a new barrel.
 
If it were me, I would find out what is wrong with the rifle. Its way easier to shop online than trouble shoot though. You just don't learn much from doing that.

Bad scope
Loose scope mounts
Loose barrel nut
Gas block touching rail or Mlok
BCG binding on gas tube
Loose gas block
Completely fouled barrel

Go down the check list, then do an ammo comparison with a few different types
 
Fantastic ideas all around, all - many thanks! I am pleasantly surprised to hear that others are having good luck with light bullets in commonly available calibers; I can have a barrel built in 1:12, etc. but that would run me more than the rifle cost; I'm not opposed to that if it will give me what I need but after all this good advice I'm going to try some different ammo - I think I was so happy with how flat the 40s are that I didn't even consider that. I'd gladly give up some flatness to get a reasonable cold bore shot!!

I'll also check that list, Arlaunch - I'm embarrassed to admit that my AR anatomy isn't great but looks like it's time to learn. I read about one guy who had a situation where something like the gas block or gas tube would heat up after the first shot and then begin pressing on the barrel, which changed the harmonics, which would absolutely create a situation like mine. He ended up bending the gas tube or something like that and the issue went away - I need to find that post again!!

Again, I really appreciate all the help, all!
 
I’ve got a 14.5” 1-8th barrel sitting if interested. I used 40gr bowlers out or it for coyotes and it shot amazing. Im
Just switching calibers now so no meed
 
Id buy another er shaw, my 6.5 grendel shoots fabulous. It was about 300.

The mizer's way would be to buy a bear creek barrel, you might have to buy 2, but I think they are 65 per. I have a 1:7 16" that is 1/2 moa but you don't want 1/7 for 40's. 1/9 is plenty.
 
I could go in a tirade of the ballistics of twist vs bullet length using the greenhill and the miller formula (boat tail formula, it doesn't work for flat base see the greenhill formula) of the "correct" bullet length to barrel twist. Which anything faster than a 1-12" twist is just overspin for the 30 to 55gr length lead core (FB and BT designs) . No doubt may will argue with me.
Which over the years I've always used the no faster than 12 twist for a 55gr length projectile rule. And it has been very successful in the projections and reality.
Noticed I used the word length, as it is actually the factor determining stability.
Stability doesn't mean accuracy, but you have to have stability to have accuracy.

Now all that being said, all of the calculations are a guide. That as a rule are very accurate. The rate of twist x the velocity = RPM's. "overspin is a sin" is a old adage that even today holds true. Brian Litz made a statement "that you can't overspin a quality bullet". Which many have misquoted over the years omitting the word quality, to argue that there is no overspin. They tend to state that Mr Litz says " that you can't overspin a bullet" which is not what the man said. He never went into what is a quality bullet when explaining to the masses (outside his books). No way am I attacking his statements. Just the misquote.

What does operspin induce? It increases the yaw, pitch, and precession (which can be too low or too fast of RPM) aspects as well as spin drift. Bullet construct goes a long way into the flight charteristics. Excessive RPM can lead to either explosive effects in some cases, to complete failure (vaporization) of the bullet at the target or before predominately with thinner jacket construction.

With all that said I have a 1-8" ballistics advantage 14.5" barrel that shoots the flat base less than 55gr length bullets extremely well, almost on par with my 1-12" twist at the 100 to almost barely 200 yard line. Where as many other barrels I have tried will fail here, producing bigger groups. Maybe the fact that the barrel is nitrated, or that the velocity loss is enough to slip into the acceptable envelope of RPM is why IDK. But how does that barrel do at the 300 yard line and beyond ? Well it fails, compared to the 1-12" and 1-14" twist. Which if I never shoot beyond the 200 yard line is a wash, it is accurate enough.

bohunr said:

Twist Rate Information​


  • .223 Remington/5.56mm NATO

    1-7:     Match or hunting bullets in the 68gr – 80gr range

    1-8: Match or hunting bullets in the 50gr – 77gr range (best all around choice)

    1-9: Match or hunting bullets in the 45gr – 69gr range
Click to expand...
Nothing against the chart nor @bohunr post but actually the 1-14" twist works the best for the 40's yet the 1-12" will work almost as well, and better in the cold environments (such as Alaska and the upper northern states including Canada). The 1-9" in my limited experience is a tweener twist, sort of a do it all, resulting in a acceptable result, just not the best for the shorter projectiles. But the posted guide is not really flawed as many simply don't offer the slow twist which explains why being omitted.
So why has the "suggested" guidelines changed over the years? Simple the market has shifted it's focus to faster twist because of buyers, all because the M16A2 used the faster twist to stabilize a 69gr tracer (yes tracers are longer than a non tracers and the amour piecing as well the material just don't have the density of lead) in the artic region of Alaska. Many thought well they (military) knows what's best, and pretty much demanded it. Not realizing that the twist was selected for a set of variable they are not really using. What's not added to Wilson Combat's chart is the 90 and 95 gr lead based length which needs a 1-6.5" twist. As well as the light weight predominately varmint grade 40-55gr FB bullets needing 1-14" to 1-12" twist for the best results. Not all bullets in a given length is the exact same weight, yet we as shooter use the weight as a guide (really it's the simplest best guide for us). Which is why some brands just shoot better than others the length is at the sweet spot measured in thousandths.

IS your head spinning now? yeah I know has the same results on me as well.

so what would I use / rather suggest as a guide for your quest? Knowing that a bullet company can just stop production of a certain desired bullet at any time based on sales?
Set a range of 1-14" (prefer the 1-12" actually) to 1-9" /1-8" twist MAX, determine just how much I honestly you want to invest in time and $$$$, to get your desired results.




"Cold Bore shot" as a term that can mean "Cold Shooter" that we as laymen use the former term almost exclusively , as we really don't like blaming ourselves which honestly is a higher probability than the bore.
There is really only one way to validate cold bore which is pretty much lock the rifle down in sand bags align to desired POI shoot "free recoil" fire the weapon eliminating the shooter induced errors (shooter is only actuating the trigger by direct or indirect methods not shouldering the weapon). For a set string of shots. In the early 1900's the Government arsenal conducted many such test using method such as a actual carriage to place the firearm in that was actually on wheels and tracks returning the carrage to the exact same position. The results was that what was determined to be "cold bore" was actually the group size. Did they allow the barrel to cool yes, the rate of fire kept down. Often result in 8 plus hours to shoot a string of 100 shots to determine the probability of hits and actual group size or more accurately the "cone of fire" term. But we don't go to that extreme. We as laymen and shooters reduce that string of shots numbers citing cost and time.
This leaves only three possibilities
a. the first round has a lower /higher velocity
b. the barrel just needs to be fouled for some reason
c. both A and B are needed (warmed up) to get to repeatable condition. Or within the geometry of the bore is a condition that simply causes a erratic some what repeatable result.

I've pretty much delved just enough into this to create more questions than answers which is true in any application dealing with a "machine" which a rifle most certainly is.
Now could your existing barrel benefit from just a simple re-crown of the barrel? yes, then maybe no, it might not help a thing but then it could. Because of erosion or concentric issues to the bore. Which in the past has been found to be more detrimental to "desired" accuracy than throat erosion in the bore as a rule, not gospel. Would I spend the money to recrown a AR Barrel ? No!!! What I would pay would just about cover the cost of a new barrel.

Could a suppressor induce a POI shift on first shot if "cold", or if removed then re-installed without indexing to the same spot. Yes it could but not always depending on manufactures.

I've used satern /liberty barrels in the past with a pretty good degree of success, Steve Satern is / was a competitive shooter and understand the pit falls. But he is not the only one. If you discuss simply your desired bullet /accuracy he would as well as any barrel maker put you on the right track with suggestions. Provided you state the focus is on accuracy vs availability (most not all will go the availability route, unless your speaking with barrel maker vs a sales person). Most of his off the shelf offering are the faster twist but, I do know he will cut you either a button pulled or rifle cut barrel to your desired specifications. Time and money, just like pacnor, Krieger, Brux, Shaw, Wilson, Lother Walther, and any other barrel producer. Occasionally one will find the "slow" twist on hand with a vendor. Mostly not so, simply because of the market demand.
Doing a quick google search for a .223 barrel in 1-12" twist I found a offering via White Oak Precision. which "might" be suitable. I've had good success with their offering in the past. Only down side is they have a 5/8x24 thread on the muzzle (actually I prefer the meater dia to the 1/2x28, and the price point to me isn't bad considering the fact that it is available, a Barrel blank would normally cost more, without profiling chambering installing the barrel extension, etc, etc for a Armalite rifle series )

www.whiteoakarmament.com

Predator Barrel .223/5.56 20

Predator Barrel .223/5.56 20
www.whiteoakarmament.com www.whiteoakarmament.com

another source could be Brownells, down side is removing the front sight assembly for a low gas block, and pencil barrel, which may or may not be acceptable.
I apologize for my being long winded in my older days.
I guess I just have a need to share what I've accumulated over the years. As honestly I could have easily just posted the link above.
(which I am now actually considering buying to have on hand for when my Satern 1-12" finally gives up the ghost after answering your question, they might be down to one LOL). Your current rig is probably great for longer projectiles. There would be no harm in have two different uppers /barrel combo's for differing purposes. Hence why I have so many different AR's.
 
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Just thought I would post this video of Erik Cortina interview of Eric Stecker which if one actually takes the time to Listen to what se says when he talks about berger. The above statement I state about RPM becomes understandable. The video is 2 hours long but luckily h hit's Berger straight off, before delving into the McMillian/defiance merger

 
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i know this is for info regarding 40 grain and twist rate in a 223 wylde.

i use a 20 inch wilson combat super sniper barrel in .223 wylde, 1:8 twist, i use federal factory ammo 53 grain v-max that shoots 1/2 at 200 yards. if that helps anyone
 
Just a thought, try something like factory 55gr ammo and see if it throws the first one out. If it does, it's not the 40gr bullet that is causing the problem with that barrel. I'd be looking for a mechanical problem.

I personally be using a slower twist with 40s. I find them more fragile in my 1-9 than in a 1-14.
 
@bohunr
bohunr said:
i use a 20 inch wilson combat super sniper barrel in .223 wylde, 1:8 twist, i use federal factory ammo 53 grain v-max that shoots 1/2 at 200 yards. if that helps anyone
Click to expand...

Not that it matters, is that a one time sample or is that the average? (understand I'm NOT disputing your posted results or stating your in error)
I believe your results to a absolute tee regardless of any calculations, regardless of the methods or group size. Not that really you need to post the answers to the questions I posed.

So really let's go down a rabbit hole just a bit (which is my mind and how I view bullet to twist, the result in me showing my homework supporting my thoughts / answers not to discount the post of others).

Hornady 53gr V-max length is 0.830"
Sierra 53gr SMK length is 0.701"
Nosler 53gr Varmageddon FB length is 0.830"

Using a 8 twist in the Miller formula calculations for the Hornady 53gr V-max (because the bullet is a BT design, otherwise the Green hill Formula for FB is more accurate, resulting in slower twist rates, than boat tail)
What is the SG factors? Stability value (SG) should be in the range of 1.3 to 2.0 to ensure bullet stability.
Please don't use stability and accuracy interchangeably they are NOT the same.
To get accuracy one has to have Stability but stability does not determine accuracy. One can only fire the bullets to evaluate accuracy. All we are at this point is keeping the bullet in a stable rotation, that effect accuracy.
Stability
Input Data
Caliber:0.224 inBullet Weight:53.0 gr
Bullet Length:0.830 inPlastic Tip Length:0.141 in
Muzzle Velocity:3200.0 ft/sBarrel Twist:8.0 in
Temperature:70.0 °FPressure:29.92 in Hg
Output Data
Stability:3.055
What about the 12 twist with the bullet and temps at the same values
Stability
Input Data
Caliber:0.224 inBullet Weight:53.0 gr
Bullet Length:0.830 inPlastic Tip Length:0.141 in
Muzzle Velocity:3200.0 ft/sBarrel Twist:12.0 in
Temperature:70.0 °FPressure:29.92 in Hg
Output Data
Stability:1.358

A perfect SG factor
Outside altitude, Temperature is a MAJOR factor.

So let's check the same bullet again and a 1-8 twist but at a colder environment say 10 degrees F vs 70 degrees above.
Stability
Input Data
Caliber:0.224 inBullet Weight:53.0 gr
Bullet Length:0.830 inPlastic Tip Length:0.141 in
Muzzle Velocity:3200.0 ft/sBarrel Twist:8.0 in
Temperature:10.0 °FPressure:29.92 in Hg
Output Data
Stability:2.709

We can observe that SG factor has actually dropped to acceptable level of the 1.3 to 2.0 envelope. so what about a slower twist??
Stability
Input Data
Caliber:0.224 inBullet Weight:53.0 gr
Bullet Length:0.830 inPlastic Tip Length:0.141 in
Muzzle Velocity:3200.0 ft/sBarrel Twist:12.0 in
Temperature:10.0 °FPressure:29.92 in Hg
Output Data
Stability:1.204

We are NOW on the bottom edge of stability


Going to the 40gr's let's just observe the length's I'll refrain from delving in any formulas (not because of results, but to keep most from just going "Jayysus TMI")
Nosler 40gr Varmageddon FBHP is 0.565"
Nosler 40gr Varmageddon FB Tipped is 0.665"
Hornady 40gr V-max is 0.686"
Hornady 40 gr Z-max is 0.691"
Sierra 40gr Blitzking is 0.677"
Sierra 40gr Varminter is 0.564"
Full stop there (if someone wishes results just say so I'll either send via PM or post on here). everything above deals with JUST stability of the bullet not accuracy.
So we have the data above there is some other values to consider.
Let's go to the bullet maker's perspective I'll quote Brian Litz of Berger bullets " one cannot overspin a quality bullet"
Quality bullet? What is that well it's several factors one being in pristine condition once leaving the bore in other words the B.C. of the bullets design is intact. And that the bullet's construction has no imbalance, no I don't expect anyone to do a Dr. Manns' version test of spinning bullets on their tips to check balance before loading them.

What is bullet failure? Well it can be when the bullet explode before making to the target as a extreme, or can in the lesser degree have been damaged altering the meaning of a "quality" bullet. Burrs, deformed noses, the list is long basically anything that results in altering the B.C negatively.
So we have a simple laymans understanding of Brian Litz statement. (all of the bullets I listed above pretty much meet Mr. Litz's statements before being fired).

Now lets go to the barrel makers perspective as the barrel is also important. I'll hope to accurately quote Frank Green of Bartlien Barrels. I was watching a interview ( 2hours worth). And the topic of rifling came up 5R vs other types groove and number of groove. He stated that he had Lake City reach out to him about some of their test using his barrels in differing grooves. They provided photos of a great many bullets fired through their flight out to 200 yards. This test took lots of hours to conduct (days weeks not sure the exact time frame), And as such the arsenal didn't give him permission to release the data that they collected but he di say what was discussed. He noted that every bullet (below .30 caliber) exhibited a burr on the side. The exception being the 5R grooved barrels. Taking that at face value, they found a very slight accuracy leaning towards the 5R at the given range of 200 yards. I think it was Frank that asked what was the size of the burrs , the response was as large as a 32nd of a inch. Next question from Frank crew on the call was did it effect the BC? they responded that is did without hesitation. IIRC he then stated if they took it out to range (meaning beyond the 200 yard line toward 400 to 500 yards etc they would / might probably see a difference. (NOTE: I'm not advocating everyone go and buy a 5R barrel whatever your using is PROBALY great, I'm merely stating the observation of L.C. test)

Personal experience with differing twist.
I found this very interesting and seemed to support my hands on experience (3 decades) with the lighter / shorter 55gr bullets in the Armalite Platform when using the M16A2 (1-7.7" to 1-7" Twist) as well as the newer series. That beyond the 200 yard range the dispersion (group size) of the bullets are to a point that a man sized silhouette cannot be accurately engaged. I've seen shooters whom always score "expert" barely make marksman (below that is unqualified) most even fail completely. Change the bullet to the issue 69gr (0.960" length) or even the Seirra 77gr SMK and then dispersion shrinks dramatically (groups tighten up) and the marksmanship levels return to normal. My personal experience wasn't alone this was to a degree that the military issued notices, and later revised manuals to reflect that 55gr was not to be used for qualification.
So between the M16A1 (1-12" twist) coupled with "correct" 55gr round and the M16A2 and newer (1-7.8 to 1-8" twist) coupled with the "correct" 69gr plus round (max range 300 meters / 328 yards) to be easier. That being said the M16A2 with the correct ammunition when you go beyond 300 meters is a absolute joy and will stomp the M16A1 in accuracy.

I highly suspect that my experience would be repeated by many on here with going to 300 yards and beyond. After I encountered this interview with Frank Green it came together and clicked. Explaining "why" the faster twist never fired the lighter bullet (55gr and below) as accurately as the 1-14" to 1-12" twist in my experience. I simply never considered "bullet failure" on the lesser side of a burr on the bullet. With the greater RPM's (faster than 1-12" T) and a reduction of the B.C. as well as the burr creating a imbalance. I think would cause everyone to the same conclusion supporting my thoughts that many would use their existing Yote gun to shoot maybe Varmints at ranges beyond what they would engage the Yote.
If the Hunter stays under 200 yard Line maybe the fast twist is OK, but in my minds eye this (frank Green's interview) really explains unexpected flyers (barring carbon buildup in the throat / inconsistent bullet seating depths, Especially in my preferred 5 shot groups, although I have used 3 shot groups, I trust 5 better is all because I'm OLD).

5R barrels can be pricey and we as average shooters tend to use the most cost effective equipment. Right fully so we are doing a "hobby" not a business such as most civilian competitors today. That being said is what drives me to recommend the slower twist in the 55gr length .224" bullet (exception the 55gr green or monolithic designs use fast twist based on length not weight).
What does all of the calculations mean? it's guide nothing more nothing less (usually we find is way more accurate than we assume). The actual fact will be when the trigger is pulled and the bullet hits the target.

(yes I do call the barrel manufactures and pick their brains on occasion as many supply the actual bullet and ammunition testing labs, that we quote in reloading and shooting.)

Have I had the EXACT results of @bohunr with a Ballistic Advantage 1-7" Twist 14.5" length Gov't M4 Profile Nitraded /QPS barrel and Speer 50gr TnT over H335??? Yes sir, I have, and like he posted I never went to beyond 200 yards. Although I suspect the groups would be horrendous and now supports or in alignment the OP's finding on his loads, would he be served with a 5R? In the same twist or simply, go to a slower twist IDK but I like @AWS say the slower twist is probably best)

Added just for consideration the actual RPM's by twist rate using 3200 fp/s as a constant
1-12" = 192000 rpms
1-8" = 288000 rpms
1-7" = 329142.8 rpm
 
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