Gunner Quinn
(Continued from Part 4.)
Barrel Length and Effectiveness
The M4 Carbine with military 14.5-inch barrels and civilian 16-inch barrels were practical for the kind of police action tactics used in the Middle East where troops regularly deployed out of vehicles and in an environment where clearing buildings was necessary. And so their gear and weapons evolved to better suit those tactics. They did however discover that when in the open in the deserts of Iraq or shooting across canyons in Afghanistan their carbines were woefully inadequate. I will justify this opinion further and later in this article.
The 20-inch barrel makes the AR-15 much more lethal at all ranges as compared to the 16-inch (or less) barrel. Using a 20-inch barrel in CQB is perhaps less than optimal, But the higher velocities produced will make it possible for a 55-grain FMJ to penetrate Level 3 body armor. The higher velocity produced is more significant as a mechanism for killing in small caliber cartridges as higher velocities are needed to impart hydrostatic shock and to improve penetration.
If the range is 200 yards and less, and If we are using the more expensive soft point or 75/77 grain open tip match (OTM) ammunition that expands and fragments, then barrel length is not so critical. However, FMJ projectiles need high velocities to be as effective as they might be. Regardless, FMJ bullets will be much less effective than expanding bullets, typically soft point or polymer tipped bullets designed for hunting, or soft lead core bullets with thin copper jackets with a hollow point that are designed for rifle match or target shooting a long range. Such are the 75/77 grain OTM bullets.
FMJ projectiles are used by the military for penetrating barriers and because they feed reliably in a variety of rifles, or most rifles, and because the Hague Convention prohibits the use of expanding projectiles that are more lethal. Polymer-tipped bullets that are typically designed for hunting can be as reliable as FMJ bullets. For barrels less than 14 inches in length, I would be using a polymer-tipped bullet that is designed to expand to compensate for the lower velocities produced. FMJ out of short barrels typically do little damage to flesh as they pass through without tumbling or fragmenting.
The 20-inch barrel produces a muzzle velocity that is generally 200 fps faster than from a 16-inch barrel. For example, the 55-grain ammunition from a 16-inch carbine barrel is generally speaking is about 2,950 fps at best, and out of 20 inches barrel the muzzle velocity can be around 3,150 fps. The 77-grain OTM ammunition is typically around 2,550 fps out of a 16-inch barrel. The 20-inch barrel produces 2,750 fps using the same ammunition. That is a significant difference as it translates into energy on target, flatter trajectories, and a better ability to buck the wind. These attributes are of practical significance on targets past 300 yards. And the length of the 77-grain OTM bullet when it tumbles and its ability to expand and fragment at all ranges from the muzzle onward make it a much more lethal projectile. It is best projectile choice for the AR-15 in barrels that are 16 inches or longer.
I suggest training with the 55-grain ammunition and using it for suppressive fire only. Defend yourself with the 75/75 grain projectiles. I’ve concluded that the 75/77 grain match ammunition is a good choice in all AR-15s including pistol-length barrels. But there could be a better choice for very short-barreled ARs.
AR-15 Pistol Length Barrels
Ounces turn into pounds and for an aging person like myself (a short old balding fat man), weight is a serious consideration especially if one is not physically fit. If we can find an upper with a pencil barrel, that would help to reduce the overall weight. Shorter barrels also reduce weight and are faster-handling.
While AR pistols are attractive, because of the greatly reduced velocity of the ammunition shot out of these very short barrels, instead of using FMJ ammunition exclusively I would use the best ammunition that I could afford. That might be .223 Remington ammunition that has the V-max projectiles manufactured by Hornady to to increase the effectiveness of the pistol-length AR platform. These projectiles have a red in color polymer tip on the front end of the bullet that also promotes reliable feeding and expands at the lower velocities created by a short barrel.
Although Hornady’s suggested application of this ammunition is for long-range shooting of varmints using full-length barrels, at the lower muzzle velocities produced by a short barrel AR pistol, the penetration and expansion or fragmentation of the V-max bullet is suitable for two-legged critters. Federal 55 grain soft point ammunition or 77 grain OTM ammunition would be a good second choice. Here is a link to Hornady’s site and the .223 Remington V- Max ammunition.
In pistol-length barrels from 50 to 55 grain varmint hunting ammunition is the best choice. I would have at least one magazine loaded with these projectiles. Another way to get the most from pistol-length barrels is to alternate FMJ with hunting ammunition. (A 50-50 mix in each magazine.) The FMJ can penetrate barriers, and the hunting ammunition will better stop the assailant. However, we could standardize on the 75/77 grain match ammunition for all our AR-15s. Here is another excellent Paul Harrell video that demonstrates the effectiveness of hunting ammunition or expanding ammunition in both 20-inch and 10.5-inch AR-15 barrels. In this video he uses 77-grain match ammunition in both barrels: AR Platforms: 10.5″ vs 20″ Barrel at 200 Yards
Paul Harrell Videos on the AR-15
The old saying is true, “Garbage in/Garbage out.” Feed the brain the best information possible before feeding the rifle and save tons of ammo and time, and be more effective. What can not be demonstrated on paper, the late, great Paul Harrell does so well to demonstrate and discuss so well here. I would pay close attention to the monologues at the end of these videos.
Videos of particular interest and value from Paul Harrell:
Because of the proliferation of the 5.56 ammunition and AR-15/M4 rifles inside of the U.S., and given the low cost to purchase and parts availability, it a “Must Have” rifle. Given my understanding of this rifle and its ammunition, I must say that in the hands of the average shooter, its strength is in its ability to provide suppressive fire.
Unfortunately, unlike the military, the citizen defender is not prepared to maneuver and can not call in an air strike. We should understand the AR-15’s relative strengths and weaknesses. The best way to compensate for its weak round is to use 75/77 grain ammunition that greatly improves its capability. “Accuracy by volume fire” is a technique that will be used by all too many people who will quickly run out of ammunition — and there will be no resupply. Every round will have to count. The 75/77 grain ammunition out of a 20-inch barrel is the most cost-effective combination that greatly improves the performance of the AR-15 platform. This combination would reduce the number of rounds that need to be fired to get the job done.
75/77 grain match ammunition is well worth the additional cost. I would only use 55-grain ammunition for suppressive fire, such as when I plan on breaking contact. M855 green-tipped 62 grain is better than M193 ball (55 grain). But I would use 75/77 grain OTM for everything else. Considering that 75/77 grain ammunition is only just slightly lower in cost than 7.62 NATO, it is my preferred ammunition for the AR-15. It needs all the help it can get to be truly effective. I much prefer a .30 caliber rounds over .223/5.56. and will use an AKM (AK-47 variant) loaded with FMJ and soft point ammunition out to 200 yards. The AKM is ideal for my terrain and wooded environment. The .300 Blackout is a better choice for ranges of 200 yards or less. But sadly the ammunition is expensive and not widely available.
7.62mm NATO is far more versatile and effective at all ranges and circumstances. Its ammunitionis the second most widely available after 5.56 NATO (.223 Remington). The lowest-priced AR-10s at Palmetto State Armory can be in the $700 to $800 range. Yes, the magazines are more than twice the price of AR-15 mags. But if I had a fire team, I would want to have at least one AR-10 or other rifle chambered in 7.62 NATO, or some other .30 caliber rifle on the team.
The Ruger Mini-14, MIni-30 and Mini-300 Blackout
The Ruger Mini rifle was the darling back in the 1980s and prior to the advent and proliferation of inexpensive AR-15s that have now flooded the market. The Ruger Mini-14 was once standard issue for law enforcement agencies that was literally in the same locked rack in patrol vehicles alongside Mossberg, and Remington 870 12 gauge pump action shotguns. I once handled one daily. These rifles have been overshadowed by the AR-15, yet they still have a place in certain states that severely restrict the AR-15.
In restrictive states, the Mini-14 is particularly important and deserves more than a brief mention. I’ll squeeze the topic into this article and suggest those who find themselves “behind enemy lines” should learn more about this handy carbine. I will say that the rifle is a scaled-down version of the M14 and shares some of it attributes. It is reliable if the factory-made magazines or other high-quality magazines are used. It is more tolerant of a lack of maintenance and is a better ‘truck gun’ than the AR-15. It is not as accurate generally speaking, but then it is plenty “battlefield accurate” and will get the job done within typical ranges that it was designed for.
The Mini-14 is apropos for the common man who has no training in maintaining the AR-15. It is a more suitable and a good rifle for self-defense, especially in states that restrict the magazine capacity of AR-15 rifles. The Ruger Mini is no longer widely known in this day and age and is overlooked as a viable arm for just about every situation the AR-15 would typically be used. With its wooden stock, it is not perceived as a ‘Black Rifle’. But, again, it can be used in the same role. Prying eyes and small minds would be less likely to be triggered if they discovered that this rifle was owned by their neighbor. And even a liberal judge would have less justification to throw the book at an owner who used one in self-defense.
The added expense of good quality Mini-14 magazines is well worth it. And I would buy additional magazines in a quantity that exceeds my minimum magazine requirement as the magazines for this rifle a much harder to come by and because bent or dented steel or alloy magazines are the primary reason a rifle may fail to feed a round into its chamber. I would trust the Mini with my life and probably shall. I know I can hit an 8″x10″ target with open sight at 200 yards with boring regularity. It certainly qualifies as a suitable rifle for infantry work.
Personally, I would choose the Mini-30 variant chambered in 7.62×39 because of my current deep stock of that ammunition. But most others would be better off choosing one in 5.56 NATO and use the M193 or M855 ammunition as the barrel twist rate of most Mini-14s will not stabilize projectiles heavier than 69 grains. The Mini will also fire soft-point ammunition reliably. This is a plus and I would use Federal 55-grain soft points, or better yet modern ammunition that uses a polymer tip that will be become deformed while stored and carried in a magazine. The Mini-14 will reliably consume soft points with deformed soft points tips and probably just about any 5.56/.223 within its capability of a 1:9 twist-rate barrel. Further reading about the Ruger Mini can be found in this 2015 SurvivalBlog review:
Ruger Mini-14, .300 AAC Blackout Tactical Rifle, by Pat Cascio
Here is a quote:
“When the Mini-30 first came out, I snapped one up. However, back then, there wasn’t much in the way of 7.62X39 ammo to be had. Additionally, the gun only came with a 5-rd detachable magazine, and everyone wanted 20 or 30-round magazines. Some aftermarket magazine makers came out with higher capacity magazines, but none were very reliable. The Mini-30 languished for a lot of years. The gun was superb in all respects, and many people don’t realize that the 7.62X39 round is very accurate in the right guns. The AK-47 doesn’t allow you to squeeze the accuracy out of this round. It was my friend and famous gun writer, the late Chuck Karwan, who told me how accurate the 7.62X39 round was, and then he demonstrated it to me in a bolt action rifle he had…”
(To be concluded tomorrow, in Part 6.)
Read the full article here