I'm looking at diving into the world of the AR-15 for the first time.  My background is primarily utilizing handguns although I have used a bolt and lever action style rifle previously.

Goal:  Have an all around 5.56 / 2.23 platform that could be used for plinking, hunting, or even SHTF if necessary.

I've noticed multiple barrel twists options listed for the AR-15 platform. Would someone be able to check my understanding to validate I'm understanding the differences correctly?

• 1/9 twist:  Typically has increased accuracy with lower grain weight bullets.


• 1/8 twist:  Capable of decent accuracy with most grain weight bullets.


• 1/7 twist:  Typically more accurate with higher grain weight bullets, but may lose some accuracy with lower weight grain bullets.

Assuming my understanding above is correct:

So, if I'm looking for a general purpose rifle barrel, it seems I would want to be investing in at least a 1/8 twist barrel.  However, I'm noting the trend seems to be a 1/7 twist barrel.  

How much of a difference in accuracy is there really between a 1/8 vs 1/7 twist barrel?

Thank you in advance.

Twist rate is more about stabilizing different bullet weights. Faster twists should stabilize heavier bullets, 1/9 should be good up to 75 or 77grains depending on the specific barrel. Unless you are shooting heavy bullets, you should be fine with a 1/7, 1/8, or a 1/9 twist.

Twist rates are driven by bullet length, the military uses 1:7 because the tracer rounds are longer than the standard 62 grain NATO rounds, the weight is the same but they are longer.
If you want to limit yourself to standard ball ammo a 1:9 will do fine. Now if you want to use 77 grain ammo you likely want a 1;7 twist.

1:9 is an anachronism from the '80s-90s.

1:8 is ideal for the greatest variety of factory ammo.

1:7 negligibly less precise with shorter bullets (55gr FMJ) and stabilizes long-for-weight bullets (62gr M855A1, 77gr TMK). Can "poof" some thin jacketed bullets - typically Hornady SX Varmint and some bad Lots of 75gr BTHP.

Most of the less expensive barrels are button rifled, the twists of which in my experience are "slower" than stamped (8 = 8.3, 7 = 7.7, etc). If two barrels are of similar features and quality, differing as 8 and 7 twist, I err with the 7, but it's not likely to be a noticeable difference.

55 Grain FMJ Ammunition Fired From AR-15s With 1:9” and 1:7” Twist Barrels


The Internet Commando: "55 grain FMJ bullets are unstable/overstabilized/inaccurate/less-lethal when fired from an AR-15 with a 1:7” twist barrel."

Statements such as the one above always seem to be proclaimed by the Internet Commando, without posting any valid, statistically significant data to support that these effects occur, or that if they do occur, that they do so to any degree that has any significant effect on the accuracy/precision spectrum involved with AR-15s firing M193-type ammunition out to distances of 100 yards.

By definition, an “unstable” bullet will have a gyroscopic stability factor of less than 1.0 at the muzzle.  A typical 55 grain FMJ bullet loaded in M193-type ammunition will have a gyroscopic stability factor of approximately 4.27 when fired from a 20” barrel with a 1:7” twist.

[CaptainObvious] 4.27 is not less than 1.0. [/CaptainObvious]


The following demonstration compares the results of firing four, 10-shot groups of the same lot of 55 grain Prvi Partizan M193 ammunition from two different AR-15 barrels; one barrel with a 1:9” twist, the other barrel with a 1:7” twist.  When chronographed from a 20” Colt M16A2 barrel, the muzzle velocity of this lot of PPU M193 was 3219 FPS with a standard deviation of 35 FPS.

The accuracy specification for M193 cited in MIL-C-9963F is as follows:
The average of the mean radii of all targets of the sample cartridges, fired at 200 yards, shall not exceed 2.0 inches.
These averages are from 10-shot groups fired from machine rested, bolt-actioned test barrels.  All things being equal (which of course they seldom are) this specification equates to a mean radius of 1 inch at 100 yards.









The first barrel used in testing was a 16” Colt HBAR with chrome-lining, a NATO chamber and a 1:9” twist.  This is the barrel found on the Colt 6721.  All of my free-floated Colt 6721 barrels have turned in sub-MOA 10-shot groups at 100 yards when using match-grade hand-loads.

The second barrel used in testing was a 20” Colt HBAR, also with chrome-lining, a NATO chamber and of course a 1:7” twist.  I've owned three of these barrels and they have all turned in 10-shot groups at 100 yards that hover just above one MOA when free-floated and shooting match grade handloads.  I purposely selected the shorter barrel with a 1:9" twist and the longer barrel with the 1:7" twist in order to exacerbate any possible statistically significant influence that the differing twist rates and intendent muzzle velocities might have on the precision of M193-type ammunition when fired at a distance of 100 yards.


Colt 16” HBAR




Colt 20” HBAR






Accuracy (technically, precision) testing was conducted from a distance of 100 yards following my usual protocol. The barrels were free-floated during testing.  The fore-ends of the weapons rested in a Sinclair Windage Benchrest and the butt-stock rode in a Protektor rear-bag. Sighting was accomplished via a Leupold VARI-X III set at 25X magnification and adjusted to be parallax-free at 100 yards. A mirage shade was used. The wind conditions on the range were continuously monitored using a Wind Probe. The set-up was very similar to that pictured below.





The Wind Probe . . .




Four 10-shot groups of the PPU M193 were fired from the 1:9” twist barrel. Those groups were over-layed on each other using RSI Shooting Lab to form a 40-shot composite group. The mean radius of that composite group was 1.08”.
As with the 1:9” twist, four 10-shot groups were fired from the 1:7” twist barrel.  Those groups were also over-layed on each other to form a 40-shot composite group; the results were nearly identical to those obtained from the 1:9” twist barrel.  The  composite group had a mean radius of 1.01”. The two composite groups are shown side by side for comparison.






The entire test as described above was also conducted using a second 16" chrome-lined, NATO chambered Colt HBAR with a 1:9" twist and a second 20" chrome-lined, NATO chambered Colt HBAR with a 1:7" twist.  The ammunition used in this test was all from the same lot of Wolf 55 grain FMJ "Performance Ammunition."  

As before, four 10-shot groups fired from each barrel at 100 yards were over-layed on each other using RSI Shooting Lab and just as before, the mean radii for these 40-shot composite groups showed no statistically significant difference.







Quality, modern lightweight bullets of copper-jacket/lead-core construction can shoot superbly from AR-15s with fast twist barrels. Typical 55 grain FMJ bullets found in M193-type ammunition do not fall into the quality category.

The 10-shot group pictured below was fired at a distance of 100 yards using 55 grain Sierra BlitzKings from one of my Krieger barreled AR-15s.  The barrel has a 1:7.7” twist.  The group has an extreme spread of 0.439 MOA.








……

From Dr. G.K. Roberts . . .

"The U.S. Army Wound Ballistic Research Laboratory conducted terminal performance testing using 5.56 mm 55 gr M193 FMJ ammunition fired in 20” barrels of 1/14, 1/12, 1/9, and 1/7 twist rates. No difference in terminal performance was noted between shots made with the different twists. Similar testing was conducted with 5.56 mm 62 gr M855 FMJ ammunition fired in 1/9 and 1/7 twist barrels. Again, no difference in terminal performance was noted."

.........


An Accuracy Comparison of M855 When Fired From AR-15s With 1:9” Twist and 1:7” Twist Barrels.







This test will compare the accuracy (technically, precision) of IMI M855 at a distance of 100 yards, when fired from an AR-15 with a chrome-lined, NATO chambered barrel with a 1:9” twist and an AR-15 with a chrome-lined, NATO chambered barrel with a 1:7” twist.  The IMI M855 is one of the most accurate and consistent loadings of all the M855 clones that I have tested.

IMI M855 is loaded with a 62 grain FMJ bullet with a cannelure. It also has a steel penetrator seated in the ogive portion of the projectile. This makes the projectile unusually long for its weight, as well as giving it a lower specific gravity. The ammunition is charged with "ball powder". The primers are sealed and crimped in placed. The bullet is also crimped in place and the case mouth is sealed with an asphalt sealant.





Chronograph data for the IMI M855 was obtained using an Oehler 35P with "proof screen" technology. All velocities listed are muzzle velocities as calculated from instrumental velocities using Oehler's Ballistic Explorer software program. All strings of fire consisted of 10 shots each.





This accuracy evaluation used statistically significant shot-group sizes and every single shot in a fired group was included in the measurements. There was absolutely no use of any group reduction techniques (e.g. fliers, target movement, Butterfly Shots).

The shooting set-up will be described in detail below. As many of the significant variables as was practicable were controlled for. All shooting was conducted from a concrete bench-rest from a distance of 100 yards (confirmed with a laser rangefinder.) The barrels used in the evaluation were free-floated. The free-float handguard of the rifle rested in a Sinclair Windage Benchrest with the aid of a Sinclair fore-arm adaptor, while the stock of the rifle rested in a Protektor bunny-ear rear bag. Sighting was accomplished via a Leupold VARI-X III set at 25X magnification and adjusted to be parallax-free at 100 yards. A mirage shade was used.  Wind conditions on the shooting range were continuously monitored using a Wind Probe. All rounds were fired from the magazine. Each upper was fired using the same lower.


The barrels used in this evaluation were both Colt HBARs with NATO chambers and chrome lining. The 1:7” twist barrel was 20” in length and the 1:9” twist barrel was 16” in length. I purposely selected the shorter barrel with a 1:9" twist and the longer barrel with the 1:7" twist in order to exacerbate any possible statistically significant influence that the differing twist rates and intendent muzzle velocities might have on the precision of the M855 ammunition.

The first barrel used in testing was 16” Colt HBAR with chrome-lining, a NATO chamber and a 1:9” twist. This is the barrel found on the Colt 6721. All of my free-floated Colt 6721 barrels have turned in sub-MOA 10-shot groups at 100 yards when using match-grade hand-loads.

The second barrel used in testing was a 20” Colt HBAR, also with chrome-lining, a NATO chamber and of course a 1:7” twist. I've owned three of these barrels and they have all turned in 10-shot groups at 100 yards that hover just above one MOA when free-floated and shooting match grade handloads.



Three 10-shot groups were fired from the upper with the 1:9” twist barrel in the manner described above. The extreme spreads for those groups measured:

2.72”
2.19”
2.24”

for a 10-shot group average of 2.38”. The three 10-shot groups were over-layed on each other using RSI Shooting Lab to form a 30-shot composite group. The mean radius for the composite group was 0.76”.



In the same manner as above, three 10-shot groups were fired from the upper with the 1:7” twist barrel. The extreme spreads of those groups measured:

2.14”
3.01”
1.71”

for a 10-shot group average of 2.29”. As before, the three 10-shot groups were over-layed on each other using RSI Shooting Lab to form a 30-shot composite group. The mean radius for this composite group was 0.68”.





...

So much not knowing what you're talking about in this thread (excepting molon who posted brilliantly accurate but slightly unhelpfully verbose information).

Calling a 9 twist an anachronism is ignorant to say the least. 1:9 is meant for mid-weight bullets in full length barrels, that's all. A 9 twist will stabilize 77gr Berger OTM from a 24" barrel but you lose a bit of BC with a Sg of ~1.3 but it works just fine.

At .223rem velocities 9 twist is optimal for 68-70gr HPBT bullets but can do much lighter or much heavier bullets. Inside the useful range of the average AR-15 it's almost the ideal compromise as long as it's not a carbine. More twist is better as barrel length gets any shorter than 20" or as bullets get longer than the 77gr Berger OTM or both.

8 twist is optimized for a different set of barrel lengths and bullet lengths, so is 7 twist. You cannot consider only the bullet length in isolation to the barrel length since barrel length is related to a point to velocity thought it's not indicative of velocity and bullet weight is related but not indicative of bullet length. Bullet length and velocity taken together is what really matters the most to selecting the best twist rate. If you plan on varminting with extremely light and fragile varmint bullets you'll want a much slower twist so you don't turn bullets into grey puffs of smoke out of the muzzle. If you're just going to mag dump 55gr FMJ into dirt then it doesn't matter a lick what you choose.

Lots of great info above. Bookmark for future reference once you have more experience with ARs.

I would suggest getting a 1:8 barrel, 16" - 18" length, to start because (if a good barrel) it will work at least ok for most commercial rounds most of the time for most things you might want to do with it.

I would then also learn how to swap barrels and handguards - it's not hard at all - and after you have some time with ARs, upgrade to a different barrel and handguard once you have refined what you want to use the rifle for.  (Or not, if you're happy with what you have.)

Thank you to everyone for their responses.  The responses have been helpful.

@Molon - I truly appreciate the effort and detail you went to with describing the precision comparison.  Plus, I love seeing technical data.  


Based on the responses, I feel a little better in my initial thoughts which was starting with a 1:8 barrel 16" in length from PSA.  I had also looked at a few other companies as well as complete package options including a Sig Sauer Tread 400 (RM400-16B-TRD) which I liked.  However, my LGS has the Sig priced at $995 at the moment which is outside my budget for now by the time I add sights.  Plus, it seems buying in pieces may potentially have a more economical advantage while allowing me the option to do some early initial build customization.  Always good to have options.

After being here for a long time, I have learned whatever @Molon says is the right answer....period

1:8 and 1:7 will shoot 52 grains up to 80 grains really well.

1:9 is not as useful to me.

basic understanding:

the twist rate stabilizes the bullet.

stability depends on bullet weight, length, and speed.

speed usually isn't a factor. length isn't so much either, but it does make a difference when the bullet is really long or really short.

ideal twist rates:

1/14, 40 grain
1/12, 55 grain
1/9, 62 grain
1/8, 69 grain
1/7, 77 grain

sure you can use the wrong grain bullet. accuracy will suffer. in some combinations the bullet will keyhole a few hundred yards downrange or even at 100 yards.

that was a basic understanding.

there is a LOT to learn about twist rate and bullets. there are equations you can use to calcualte the right twist you need for a bullet, or the right bullet for a twist, and long range stuff such as stability factor, spin drift, how it affects ballistic coefficient, on and on.

I've heard that a fast twist can impart so much gyroscopic stability, that at long distance when the bullet starts to drop substantially, it does not "nose down" but rather maintains its upward pitch. Thus it is no longer flying straight through the air and retaining its ballistic coefficient.

If this is true, you may not see any difference in accuracy at 100 yards (comparing fast twist to slow twist), but you could see a big difference at something like 500 yards.

Anyone know if there is truth to this?

Testing performed by C.E. Harris at Aberdeen Proving Ground and later at Sturm-Ruger has shown that the “overstabilization” claim is largely nonsense. The testing showed that “overspinning” quality light-weight bullets from a fast twist barrel does not become an issue unless you have a gyroscopic stability factor greater than 5.0 (which would require something along the lines of a 1:6” twist barrel launching a 55 grain bullet at over 3500 fps) or unless firing at an angle greater than 85 degrees.

After the U.S. Military adopted the 1:7” twist for the M16A2, C.E. Harris conducted testing comparing the accuracy of light-weight bullets fired from 1:10” twist barrels and 1:7” twist barrels using 52 grain Sierra MatchKings. The accuracy testing was done from 200 yards, (well into the downward slope of the trajectory where the Internet Commando claims that all manner of evil befalls the “overstabilzied” bullet), and the accuracy results from the two different twist barrels were nearly identical.

Very interesting thanks!

yep I heard that too. and the bullet is slowing down greatly at long range, so it's dropping quickly. making the angle steep. with the nose still pointing up it can hit the target at a 30 degree angle. happens at like 700 yards or whatever.

also you get excessive spin drift.

you can get away with a lot of overstabilization, but you can't get away with understabilization.

a stabilization factor of 0.84 will keyhole 100% of the time at 25 yards.

it depends on what weight of bullets you are going to shoot.

I can't tell if 1/7 barrels are selling more because everyone wants to shoot 77 grain or because that's what the manufacturers are pushing regardless of what people want.

a general purpose barrel would be 1/9 twist. if you are shooting mostly 69 grain then get a 1/8. if you are shooting mostly 77 grain then get a 1/7.

77 grain sucks for short range shooting. if you are doing 500 yards and less you want 55-62 grain and a 1/9 barrel.

Ya think?

...

Your mouth is talkin'.  You might wanna look to that.











...

This is inaccurate for many reasons.

terminal performance.

what are the reasons

When you find yourself in a hole, the first thing to do is stop digging.

....

A lot longer and have a lower specific gravity.








....

Must disagree.  It is bullet length not weight.  Length and velocity.  For instance long for weight bullets (all copper monolithic bullets come to mind) may require faster twist than jacketed lead core bullets of the same weight.

A 70 grain copper Barnes TSX bullet is longer than a 77 grain Sierra Match King (SMK).  I have a particular older 1:9 twist 16" barrel that can shoot 70-75 grain lead core bullets with great accuracy.  It will shoot 77 SMKs well if pushed fast enough.  But it badly keyholes the longer but lighter 70 TSX bullets.  They hit sideways often missing tbe target entirely at 100, but shoot beautifully from 1:8 twist 16" barrels.

Of course, 1:8 well-stabilizes any commercially available .223/5.56 ammo that can cycle through an AR15 magazine regardless of bullet weight.

I have very fast 35 grain Hornady Superformance varmint .223 ammo that shoots very accurately from even 1:7 twist barrels.  As others have stated, its difficult to over stabilize a bullet, but you certainly can under stabilize very long ones.

In my experience 77 grain SMK or Berger 77 OTM match bullets DO shoot sub MOA from match barrels at 100 yards.  While a 52-53 grain flat based match bullet may shoot tighter groups at 100-200 yards where wind deflection is less an issue, the longer match match grade 77s are still very accurate at short distances.

FWIW, my 52gr Berger FB handloads in Lapua Match cases are sub 1/2 MOA capable at 100 yards from a Lilja 16" 1:8 twist match barrel when I don't screw up.  77gr Berger OTMs in the came cases are a little less accurate at 100, but still well under 1 MOA.  These are all carefully worked up handloaded match grade component ammo.

1. I know that. was trying to keeping it simple. if you want the full pizza go to http://nuke.42web.io/ar15w.html and read sections

4.3.4 THE MECHANICS OF TWIST AND BULLETS
4.3.5 TWIST RATE TABLES FOR .223/5.56
4.3.6 TWIST RATE EQUATIONS

2. I'll say it a second time, 77 grain sucks for short range shooting BECAUSE OF TERMINAL EFFECTS.

3. that 35 grain varmint bullet in a 1/7 twist is the most likely thing to explode or prematurely fragment upon impact (too shallow penetration) varmint bullets have a thin jacket.

You can regurgitate your Internet Commando BS as many time as you want, but it's still BS.
The 77 grain Nosler OTM performs extremely well at short ditances.




....

shut up, goofball

Muzzle velocity is very important.  The RPM the bullet revolves at is the source of gyroscopic force that stabilize the bullet, and that is the twist (in revolution per inch) X the muzzle velocity (in feet per second) X 720.

Also, 55 gr FMJ have a better stability margin if used in 1:10

I agree with 1:10 vs 1:12.

Disagree with the importance of velocity.

55gr/0.750" bullet, 3200fps, 1:12, 60*F at sea level - SG 1.31.
3000fps - SG 1.28
2800fps - SG 1.25
3000fps, 1:10 - SG 1.85

M193
weight: 54.9 grains
length: 0.760"

M855
weight: 61.7 grains
length: 0.906"

SF= [(30*M)/(T^2*d^3*L*(1+L^2))] * (V/2800)^(1/3)

where
SF= stabilization factor
M= bullet weight in grains
T= barrel twist in calibers per turn (not inches!)
d= diameter of bullet (= caliber)
L= length of bullet in calibers (a 0.750" long M193 is .750/.224=3.35)
V= velocity in ft/s

M193 SF at range, 20" bbl
yds>__0____100___200___300___400___500___600
ft/s>_3240__2836__2468__2128__1817__1539__1305
1/7___3.71__3.55__3.39___3.23__3.06___2.90__2.74
1/8___2.84__2.72__2.59___2.47__2.34___2.22__2.1
1/9___2.24__2.15__2.05___1.95__1.85___1.75__1.66
1/10__1.82__1.74__1.66___1.58__1.50___1.42__1.34
1/11__1.5___1.44__1.37___1.31__1.24___1.17__1.11
1/12__1.26__1.21__1.15___1.10__1.04___0.99__0.93
1/14__0.93__0.89__0.85___0.81__0.77___0.72__0.69

M855 SF at range, 20" bbl
yds>___0___100___200___300___400___500___600
ft/s>_3020__2712__2422__2149__1893__1654__1432
1/7__2.46___2.38__2.29___2.20__2.11___2.02__1.92
1/8__1.89___1.82__1.75___1.68__1.61___1.54__1.47
1/9__1.49___1.44__1.38___1.33__1.28___1.22__1.16
1/10_1.21___1.16__1.12___1.08__1.03___0.99__0.94

these show that barrel twist has more of an effect on SF than a relatively small change in velocity.

velocity can be ignored for rough estimations. there is a seperate equation for that which does not include velocity. it is, however, important when considering the range over which you are shooting.

these tables show that 1/12 is optimal twist for M193 out to 450 yds (as intended for that ammo) and 1/9 is optimal twist for M855 out to 600 yds on this table, out to 1100+ yds when you see the full table.

This comes up all the time. For bullets 52 grains and up, 1:8 and 1:7 are what you need.

1:9 just won’t match the faster twists.

100% this, down to every last word.

And the 22er posting false information continues to shit in a tech thread.


….

1:9 IS a faster twist!

The original AR-15's were 1:14!

Later changed to 1:12 for better stabilization in blow zero arctic conditions.

The only thing 1:9 won't do is stabilize super long for caliber 75-80gr bullets that didn't even exist when the 1:9 was adopted as the de facto commercial standard.

It does everything else including 69gr SMK's just fine.

My particular 1:9 barrels even shoot the 77gr bullets fine, but that's not a guaranteed outcome in the "Slow Twist" 1:9 barrels.

yeah right. show me how anything I said is false. prove it to me. come on, you have to convince me otherwise you're wrong.

hop to it! if you don't answer I must be right and you are vanquished! hahahaaa

Have you ever killed anything with 77gr ?

I have, it works very well.

.
.
.

OP, 1:8 or 1:7 is good to go.

1:9 usually won't stabilize 77gr. ( it will shoot, but not accurately )

yeah, no. OP if you are using mostly 69 grain you want 1/8, if you are using 77 grain you want 1/7, and for general purpose you want 1/9.

and 77 grain sucks for short range. within 300 yards you want 55 grain. or 35-45 grain varmint bullets for the woodchucks.

77gr is so awful people are using it to kill big game.

Every post of yours is wrong, trashy, or trolling. Mods, please remove this retread.

and now they're killing elephants with it.

sorry, you aren't convincing me. and quit trolling.

22er, put some respek on this board.

you take a look at the posts above, and see if any respect was given to me.

do you see any?

then take another look and tell me if disrespect was given  to me.

13'er

Hello everyone

I thought I'd drop back here to say I did eventually end up buying my first AR-15.  I actually picked up a SW M&P15 Sport II (SKU 10305) from my local gun shop.  I ended up going with the 1/9 twist since most of the ammo I would be shooting would be more general purpose in nature for now.  I figured start with the basics, but also buy a complete setup that should be a reliable setup from a respectable manufacturer.
Thank you to everyone for their input.

Great choice!

Like I said earlier you will be good to go with any ammo up to 69 grains.

You can pick 1/8, 1/7.7, or 1/7 and not tell a hill of beans in difference. Do not think twist of some level = accuracy. A well made barrel = accuracy regardless of twist. A 1/7 is a better choice IMO for shooting the preferred 77 grain ammo. The 77 grain ammo is preferred even for short barrels because the 77 grain ammo performs better terminally and to a longer distance due to lower velocity threshold. The only exception being bonded soft point bullets or all copper bullets that do better with a lighter 62 grain-ish bullet. This is all a very .223/5.56 specific thing and is not a general rule. Lighter .223 bullets under penetrate if they fragment unless fragmentation is delayed. It is a limitation of mass due to caliber when shooting deer, pig, or human sized things.

1/7 is also my choice for 300 BLK due to shooting heavy subs and still allowing 1 MOA groups with supersonic 110s.

Generally, I prefer slightly faster twist when given a choice. It allows more choices of high BC modern bullets. The negatives are minimal to not noticeable for me.

77 grain Sierra SMK and 75 Hornady OTM produce the largest wounds in yawing .223/5.56 bullets.

77 TMK produces the largest wounds in .223/5.56 bullets.

This holds true if you need to reach the 12" minimum FBI penetration lower limit for human, deer, or pig sized living things.

If you just shoot small rodents, lighter is indeed better terminally because ot is faster and more violent for the 6-10" the lighter ballistic tips penetrate.

For bullets that yaw to fragment like 55 or 62 grain FMJ, those have a thicker jacket and/or the shorter length requires a higher velocity to fragment, thus they fragment less, stop fragmenting at shorter ranges, and can have a delay to yaw enough to fragment. They are worse in every way terminally compared to 75/77 grain match bullets, which have faster yaw, larger wounds, and perform at further ranges.

Hope that adequately covers why you are wrong.

QFT

that's a good carbine, you will love it.

put a quality red dot on it, and a good sling, I like the VTAC


Remember, you can buy other uppers and swap them out.

after a while you'll visit your FFL, and buy another lower for your extra upper

then you will buy another upper, maybe in 6.8SPC, 6.5G, or 300BK

another trip to the dealer, and WOW, lowers are on sale.

this is how black rifle disease begins.

. . . the cure is a bigger safe

You can shoot anything you can fit in an AR magazine in a 1/7 and it won’t lose BC or accuracy for lack of stability. You can’t say that even with 1/8 twists.