Anyone else using a .350 Legend AR-15 for home/self defense . . . or considering it?
I'm well aware the .350 Legend was developed as a straight wall medium game hunting cartridge, notably for deer in mostly mid-west flatland states that have straight wall rifle cartridge hunting laws to limit effective range, and designed to be used in an AR-15 platform with an AR-15 lower, upper (baarreled and chambered for it), and bolt. Magazines are another matter. Apparently Indiana is a mix depending on land ownership . . . private vs public . . . from what I've read on it.
This isn't about hunting, though. It's about using a 16" mid-length AR-15 chambered in .350 Legend for self and home defense, which shouldn't need more than about 50 yards absolute max. I'm thinking the 160 grain Winchester Defender with its bonded, protected hollow point would be the most likely candidate in 20-round C-Product (aka Duramag) steel magazines. Haven't seen anything like it from the other ammo companies -- they (along with Winchester) are pursuing the hunting market.
Muzzle Velocity and Energy: 2225 fps and 1759 ft-lb
50 yard Velocity and Energy: 1976 fps and 1388 ft-lb with 0.3 inch rise (100 yard battle sight zero).
I'm not a huge fan of Muzzle Energy as an evaluation of cartridge efficacy. It goes up with the square of velocity. A very light bullet with huge velocity has enormous energy that belies observed efficacy. Momentum, however, is equally linear with mass and velocity (essentially co-equal in effect). Ran it through the Stopping Power Calculator, an iPhone and Android App, to see what it came up with. Taylor TKOF and Thorniley SP aren't very applicable as they're made for big bore rifles and huge, dangerous game. However, the Hatcher RSP and RSP expanded (for hollow point), created for evaluating small arms military rounds were quite good, especially compared to 64 grain .223 ammo (Winchester Silvertip Defense Tip).
Hatcher RSP = 87; expanded (expanding soft point / or hollow point) = 107
Higher score is better; Hatcher considered anything over 50 a reliable 90% man-stopper with a center of mass thoracic hit.
By comparison, for the 64 grain .223 Winchester Silvertip Defense Tip (not the hunting round):
Hatcher RSP = 15; expanded = 20
According to Hatcher, below 30 has a 30% one-shot stop and 30-49 a 50% probability. That is an interesting result, perhaps due to not considering other terminal ballistics characteristics such as very high velocity tumbling and yaw, which weren't as well known in the mid-1930's. Nevertheless, the reduced effectiveness of the 5.56x45 NATO round was immediately noted in the Sand Box when the 20" M16A2 was replaced by the 14.5" M4A1. This has prompted DoD evaluating a replacement for it, such as the Sig Fury (currently outrageously expensive). The .458 SOCOM (or .450 Bushmaster) would also be a Big Thumper, but very expensive, and building AR's with it seems to have run its course. Don't need 300 meters unless TEOTWAWKI Apocalypse occurs. For that there's the 5.56x45mm in plentiful quantity.
Thoughts on .350 Legend Self/Home Defense use?
Notes on Hatcher RSP:
Created by Major General Hatcher (US Army) in the mid-1930's in the Ordnance Department at Aberdeen Proving Ground for evaluating cartridge effectiveness against enemy personnel. Uses bullet mass, velocity, projectile frontal area (a function of caliber), and bullet form factor (shape) to account for spitzer vs round nose, hollow point, etc. High energy with low mass and bullet diameter don't fare well with TKOF, Thorniley SP or Hatcher's formulas. Hatcher favors the larger bores, such as .45 Colt, .45 ACP and .44 Magnum, and expanding bullets versus FMJ.
For the geeks, discussion about Hatcher's formula and his development of it is here:
http://firearmshistory.blogspot.com/2012/12/measuring-effectiveness-of-cartridges_28.html
I'm well aware the .350 Legend was developed as a straight wall medium game hunting cartridge, notably for deer in mostly mid-west flatland states that have straight wall rifle cartridge hunting laws to limit effective range, and designed to be used in an AR-15 platform with an AR-15 lower, upper (baarreled and chambered for it), and bolt. Magazines are another matter. Apparently Indiana is a mix depending on land ownership . . . private vs public . . . from what I've read on it.
This isn't about hunting, though. It's about using a 16" mid-length AR-15 chambered in .350 Legend for self and home defense, which shouldn't need more than about 50 yards absolute max. I'm thinking the 160 grain Winchester Defender with its bonded, protected hollow point would be the most likely candidate in 20-round C-Product (aka Duramag) steel magazines. Haven't seen anything like it from the other ammo companies -- they (along with Winchester) are pursuing the hunting market.
Muzzle Velocity and Energy: 2225 fps and 1759 ft-lb
50 yard Velocity and Energy: 1976 fps and 1388 ft-lb with 0.3 inch rise (100 yard battle sight zero).
I'm not a huge fan of Muzzle Energy as an evaluation of cartridge efficacy. It goes up with the square of velocity. A very light bullet with huge velocity has enormous energy that belies observed efficacy. Momentum, however, is equally linear with mass and velocity (essentially co-equal in effect). Ran it through the Stopping Power Calculator, an iPhone and Android App, to see what it came up with. Taylor TKOF and Thorniley SP aren't very applicable as they're made for big bore rifles and huge, dangerous game. However, the Hatcher RSP and RSP expanded (for hollow point), created for evaluating small arms military rounds were quite good, especially compared to 64 grain .223 ammo (Winchester Silvertip Defense Tip).
Hatcher RSP = 87; expanded (expanding soft point / or hollow point) = 107
Higher score is better; Hatcher considered anything over 50 a reliable 90% man-stopper with a center of mass thoracic hit.
By comparison, for the 64 grain .223 Winchester Silvertip Defense Tip (not the hunting round):
Hatcher RSP = 15; expanded = 20
According to Hatcher, below 30 has a 30% one-shot stop and 30-49 a 50% probability. That is an interesting result, perhaps due to not considering other terminal ballistics characteristics such as very high velocity tumbling and yaw, which weren't as well known in the mid-1930's. Nevertheless, the reduced effectiveness of the 5.56x45 NATO round was immediately noted in the Sand Box when the 20" M16A2 was replaced by the 14.5" M4A1. This has prompted DoD evaluating a replacement for it, such as the Sig Fury (currently outrageously expensive). The .458 SOCOM (or .450 Bushmaster) would also be a Big Thumper, but very expensive, and building AR's with it seems to have run its course. Don't need 300 meters unless TEOTWAWKI Apocalypse occurs. For that there's the 5.56x45mm in plentiful quantity.
Thoughts on .350 Legend Self/Home Defense use?
Notes on Hatcher RSP:
Created by Major General Hatcher (US Army) in the mid-1930's in the Ordnance Department at Aberdeen Proving Ground for evaluating cartridge effectiveness against enemy personnel. Uses bullet mass, velocity, projectile frontal area (a function of caliber), and bullet form factor (shape) to account for spitzer vs round nose, hollow point, etc. High energy with low mass and bullet diameter don't fare well with TKOF, Thorniley SP or Hatcher's formulas. Hatcher favors the larger bores, such as .45 Colt, .45 ACP and .44 Magnum, and expanding bullets versus FMJ.
For the geeks, discussion about Hatcher's formula and his development of it is here:
http://firearmshistory.blogspot.com/2012/12/measuring-effectiveness-of-cartridges_28.html