Winchester was kind enough to furnish some ammunition for me to review in both .223 Remington, 5.56x45mm NATO and 7.62x39mm Russian. The .223 load was their 69 grain Match round while the 77 grain one was the 5.56mm Match load. All of the rounds were tested for accuracy, and it was a very pleasing experience.
I should point out that while .223 and 5.56 look like the same round, the military 5.56 chamber is slightly different and can handle more pressure, so 5.56 ammunition should not be used in .223 chambers. It is acceptable, however, to use the lower pressure .223 rounds in a chamber marked for 5.56. This means, of course, that 5.56 ammunition generally offers more velocity and hits harder than .223 ammo.
The .223 and 5.56 ammo was tested in two AR’s. The first is a Lewis Machine and Tool (LMT) Defender. LMT is a brand usually considered in the top tier of AR quality. It has a standard M4 barrel profile, which means it is .750 inches in diameter from the gas port to the muzzle and reduced to .650 inches under the handguards to save weight. This one also has the cut for the M203 Grenade Launcher, which isn’t of much use to most of us. It is chrome lined and has a 1:7 twist rate to stabilize heavy bullets, like the 77 grain one being tested. The barrel is 16 inches long, however, unlike the M4 which has a 14.5 inch barrel. This is to meet federal regulations on short-barreled rifles without having to pin or solder the muzzle device on. You also get slightly more velocity.
The other AR is a home-built with a Bravo Company upper receiver and bolt carrier group and a Daniel Defense 16-inch Light Weight barrel that is .650 inches in diameter for its full length. It is also chrome lined and has a 1:7 twist rate. The thinner barrel is cold hammer forged, which many consider a superior method of barrel making, though there is much argument over the issue. LMT didn’t specify how their barrels were made at the time this carbine was manufactured.
I have grown to really like lighter barrels as they are far handier than the heavier ones. The difference is only a few ounces, but it feels like more. The only drawback to the lighter barrel would be if you are shooting a lot in a short time frame, as you might with an automatic weapon in a firefight. Since very few of us have automatic AR’s, that’s not likely to be an issue unless we work hard at it.
Neither AR has a free floated barrel, which usually but not always improves accuracy. The biggest advantage of free floating the AR barrel may be the fact that you can use a tight sling or rest the handguard on a support without causing barrel deflection.
Both carbines are capable of reliably shooting close to 1 minute of angle (MOA) groups using the right ammunition and a Leupold Vari-X 3.5-10x50mm scope. This is not, of course, going to win a bullseye match, but it is very respectable accuracy from short-barreled defensive weapons.
The 7.62×39 was used in a Century Arms C39V2, a U.S.-made AK-47 I reviewed recently, and a CMMG Mutant, which is a U.S.-made rifle I will be reviewing shortly. The Mutant is a very fascinating design based on the AR platform upsized for the Russian cartridge and using AK magazines. Both weapons have 16-inch barrels.
The .223 cartridge started life with bullets in the 55 grain range, but as shooters tweaked it for accuracy they experimented with heavier bullets with higher ballistic coefficients (BC). The higher the BC, the less a bullet is slowed by drag from air as well as the less it is affected by wind. A light bullet with a low BC may start fast; however, like the tortoise and hare fable, the heavy bullet with a high BC can win the race by retaining velocity and not being pushed off course by a cross wind.
Competitors still like the light bullets for shorter range matches, but as they go past 300 yards or so they began to see big advantages with 69 grain bullets. The Sierra MatchKing 69 grain bullet has turned out to be something of a gold standard for accuracy in rifles with the right barrel, which means having a 1:9 or faster twist rate.
Dabbling further, past 500 yards, shooters began trying 77 grain and heavier bullets with excellent results. The 77’s, however, are the heaviest that they have been able to get to work in AR magazines. Heavier ones are simply too long to fit, so they are used for hand fed single shots in slow fire or in bolt guns with longer magazines.
The Winchester Match 69 grain load uses the storied Sierra MatchKing bullet, while the 77 grain one uses the well regarded Nosler Custom Competition bullet. The 77 grain load appears to have the primers sealed with lacquer, while the 69 grain does not. The primers on both appear to have a slight circular crimp applied but nothing like the heavily-staked crimp found on most military ammo. That makes the brass better for reloading, but AR’s sometime have issues with primers popping out, hence the staking on military ammo.
When I pulled the bullets, I found the cartridge case is heavily crimped into the 77 grain bullet, while there is just a hint of a crimp on the 69 grain one. The 77 grain bullet has what appears to be a black asphalt sealant on it, so the 77 grain load should be far more weather resistant, and weather resistance is a feature that should be of interest to preppers.
I had 40 rounds of each load, and all functioned perfectly with no failures. Muzzle blast and flash were typical of .223 ammunition fired from this sort of rifle. The testing was done in an indoor range, and flash was well contained by the Yankee Hill flash suppressors mounted on both weapons. I would have liked to try a few rounds in total darkness, but I don’t have access to a range at night at the moment.
The 69 grain load has the following ballistics, according to Winchester:
I got an average of 2,735 feet per second at the muzzle out of the 16-inch barreled AR’s, which makes me think Winchester used a longer barrel for their figures.
The 77 grain load ballistics from Winchester are:
With this load, I got a 2,732 feet per second average, which impressed me. A Winchester spokesperson said they measured these with 16-inch barrels, and that jives with what I got. That makes this a much hotter load than the 69 grain one.
Accuracy with both loads was good, though I was a bit frustrated with the LMT. It has yet to like a 77 grain bullet, though it has always done well with anything with a 69 grain MatchKing. The homebuilt AR with the Daniel Defense barrel, on the other hand, seems less finicky and shoots well with both bullets, though not as well with either as the LMT does with a 69 grain bullet.
The groups were shot at 100 yards at an indoor range, and the targets were analyzed with OnTarget, a $12 program that allows you to scan targets, input the bullet holes, and let it compute a very useful array of data. This is far easier than playing with a ruler and calculator, and it allows easy archiving of information.
The center to center (CTC) figure is what most of us traditionally measure as group size. It is the distance from the center of the two holes that are the farthest apart.
The average to center of group (ATC) figure may be more useful, however, as it gives us the average distance from the aiming point that a bullet will hit. This is actually what we want to know, how close our shot will come to the aiming point, but the problem with this measurement is that you could have a load and weapon combination that produces a flyer in every group. In other words, you could have several shots go through one hole but one that hits 10 inches out. The average might look okay, but if there are consistent fliers you will have trouble.
I like looking at both CTC and ATC as CTC will warn you about fliers while ATC lets you predict how close your shot will likely fall. The group width and height can give you an idea of which way the groups spread. I often find patterns, and if you know what they are it might help get a hit someday.
I shot five shot groups and used the data from the worst group with each rifle and load. While I’m not the best shot, sometimes I get lucky. I figure it is better to assume worst case than run with the best case. With these loads, the groups were pretty consistent. Ten shot groups are a better idea, but I usually am more consistent with shorter strings, and I like to let barrels cool a bit between groups.
Some of you may be wondering why I am interested in match loads, since this is a prepper site and not a match one. One reason is that I think it is important to have a known, consistent load for each rifle. This would be one that tells us all something is wrong if it won’t shoot well. The sights or action screws could be loose or something else has gone wrong. It also might be that we are just having a bad day. I have spent a fair amount of time testing things only to discover there was a problem I would have caught if I had only started and finished with my known good load.
The next thing is that we may need to make a precise shot at long distance, and having some primo high-grade ammo can help us make it.
A final reason is that the 77 grain match loads have turned out to be very effective rounds for self-defense use. All the work by competitors with them paid off when the US Special Ops troops wanted something capable of greater range and accuracy than their standard AR’s and developed the AR-based MK 12 Special Purpose Rifle. Black Hills Ammunition came up with the Mk 262 match grade round, using 77 grain open tip match (OTM) bullets, that allowed troops to make the best of the new rifle.
The rifle and round came in very handy as troops deployed to the open terrain of Iraq and Afghanistan and discovered that their lighter bullets weren’t delivering the desired performance in accuracy or stopping power. Soldiers equipped with the MK 12 rifle and MK 262 ammunition, however, had much better results. As well as superb accuracy, the 77 grain match bullets also delivered excellent wound ballistics– far better than the standard M855 round. Not only did it work better in the 18-inch barreled MK 12 rifle, but it also worked better in the 14.5 inch barrel M4, making it a very popular item on the front lines.
The one deficiency that I’ve seen noted with it is when there are intermediate barriers, such as auto glass between the shooter and target. Dr. Gary Roberts is a Navy reserve lieutenant commander who studied at the Army Wound Ballistics Research Laboratory and serves on the staff of Stanford University Medical Center. He also consults with federal, military, and law enforcement on wound ballistics and has done extensive research on .223 ammunition. He feels that the 77 grain bullet is not the best choice for getting through barriers in front of the target, even though it performs very well otherwise. It is, on the other hand, a great choice when one is concerned about over penetration.
The end point of this discussion on the MK 262 is that the Winchester 77 grain Match load should be very close to the same round. While the current version of the MK 262 uses a Sierra bullet, there were versions that used the Nosler found in the Winchester round. The velocity is essentially the same as the MK 262, thus the Winchester should make an excellent defensive round.
The 69 grain bullet, however, according to Roberts, does not match its heavier sibling in regard to wound ballistics, so it isn’t a good choice for defensive use. It should be relegated for accuracy testing.
The 7.62x39mm ammunition also worked flawlessly in both rifles. I had 60 rounds of the PowerPoint and 100 rounds of the FMJ. I followed the same procedures as I did with the .223 ammo with the Mutant, but since I did not have a mount to use optics on the C39V2, I had to use its open sights; its groups were not as good as they could have been.
The PowerPoint was clearly the winner in the accuracy category and would be the choice for self-defense as well. Roberts has tested this cartridge, and it is one of the loads he picks for 7.62×39. He notes that it also performs well through auto glass and should make an excellent round for hunting. I was especially impressed with PowerPoint in the Mutant. Many of us have discounted 7.62×39 as being inaccurate, but it is clear that you can get good accuracy with it in the right gun using the right load.
I didn’t find any information on how the Winchester FMJ round might work for defensive use, but Roberts notes a lot of variation in the performance of FMJ loads. Some yaw quickly in flesh and cause a lot of damage, while others simply sail through leaving a small wound. It is clearly a decent round for practice and plinking and, unlike the cheap imported stuff, it offers the advantage of quality reloadable brass, if you want to reload your ammunition.
I didn’t see any evidence of primer sealing on either load, nor did I find any sealant on the bullets. The bullets were both crimped into the case, but the primers didn’t have any noticeable crimping.
Personally, if I were using a 7.62×39 for defense, I would lay in a stock of the PowerPoints for serious use and use the FMJ for practice. One nice thing I noted is that the two rounds shot pretty close to the same point in both guns.
The PowerPoint and Mutant combination have made me think far better of this cartridge. Watch for the Mutant review, which should be up next.
– SurvivalBlog Field Gear Editor, Scot Frank Eire