Hornady Critical Defense 308 155gr FTX – Commanding Rifle Load

Description

The Hornady Critical Defense 308 155gr FTX is the biggest thing in the Critical Defense line, and it works from a different starting point than the handgun loads. A 155 grain FTX at 2785 fps carries about 2669 ft-lbs, so energy was never the problem. The engineering goes into making the bullet behave predictably however short the barrel it leaves.

• Hornady Critical Defense 308 155gr FTX Overview
• 308 Home Defense Ammo Ballistics
• Why The 155 Grain FTX Bullet Opens At Low Velocity
• Specifications
• Rifles That Suit This Short Barrel 308 Defensive Load

Hornady Critical Defense 308 155gr FTX Overview

Hornady item 80920 loads a 155 grain FTX bullet to a nominal 2785 fps, producing roughly 2669 ft-lbs at the muzzle. Twenty rounds per box.

Hornady publishes the curve from a 24 inch test barrel: 2785 fps and 2669 ft-lbs at the muzzle, 2499 fps and 2150 ft-lbs at a hundred yards, 2231 fps and 1713 ft-lbs at two hundred, and 1980 fps and 1349 ft-lbs at three hundred.

Most 308 rifles kept for defence wear a 16 or 18 inch barrel rather than 24. Expect roughly a hundred to two hundred feet per second below the published numbers, which is exactly the case the Flex Tip is designed to cover.

One thing worth saying plainly: a 308 indoors is a great deal of cartridge. It penetrates interior walls readily, the muzzle blast in a confined space is punishing, and for most people a 223 carbine or a shotgun is the better house gun. This load makes most sense in a rifle kept for a property rather than a bedroom.

308 Home Defense Ammo Ballistics

At 2785 fps a 155 grain bullet produces about 2669 ft-lbs, from grains times velocity squared divided by 450437. That is more than double what the 223 versions of this load generate and roughly seven times a service pistol cartridge.

Energy retention is excellent. Still carrying 1349 ft-lbs at three hundred yards means the round is nowhere near the edge of its envelope at any distance a defensive situation occurs at.

The trajectory is flat and the recoil is real. A 308 is a full power rifle cartridge, and in a light carbine the muzzle rise costs you time between shots in a way a 223 does not.

Hornady also loads low flash propellant. A full power rifle cartridge fired in the dark produces a substantial fireball with ordinary powder, and 308 home defense ammo that blinds you at the moment you need to see is worse than useless.

Why The 155 Grain FTX Bullet Opens At Low Velocity

The Flex Tip does two jobs. The first is familiar: a conventional hollow point driven through heavy clothing can pack its cavity with fabric and then behave like a solid, passing through without opening. A polymer filled cavity cannot pack.

The second is about velocity, and in a rifle it is the more important of the two. A short barrelled 308 and a very close target are both situations where a hunting bullet can arrive outside the window it was designed for. Hornady states that the Flex Tip helps the bullet expand at low velocities, and that is what separates this from a deer load in a different box.

The FTX is a spitzer with a boat tail, so it is not giving up ballistic performance to get there. The polymer tip actually improves the ballistic coefficient over an exposed lead nose, which is why the energy retention figures hold up so well.

The trade against a dedicated hunting bullet is penetration on heavy game. A controlled expansion hunting bullet built to drive through an elk shoulder is a different design brief, and Hornady sells those separately.

Nickel plated cases round it out. They resist corrosion in long term storage, and the bright case mouths make a loaded chamber easier to confirm by eye in poor light.

So the brief for a short barrel 308 defensive load is narrow and the 155 grain FTX bullet meets it: open reliably at whatever velocity it arrives, and do it without giving up the trajectory the cartridge is known for.

Specifications

Rifles That Suit This Short Barrel 308 Defensive Load

Any rifle chambered in 308 Winchester in sound working order will fire this load, and that includes rifles chambered in 7.62x51mm NATO. The two are dimensionally compatible, though a 308 chamber is the tighter specification of the pair.

Practically that covers the AR-10 pattern rifles, the Springfield M1A, the Ruger Scout and American, the Remington 700, the Savage 110, the Tikka T3x and the many bolt actions built for the cartridge.

Twist rate is a non-issue. Every 308 barrel made is 1:10, 1:11 or 1:12, and all three stabilise a 155 grain bullet comfortably.

Sight in with the load you intend to keep in the rifle. A high energy rifle defense ammunition load at 155 grains prints differently from the 168 and 175 grain match bullets many 308 owners zero with.

High Energy Rifle Defense Ammunition Availability

This Hornady Critical Defense 308 155gr FTX is in stock and ships from our Collegeville, Pennsylvania shop. MAG5 Firearms is a family owned FFL dealer, and orders of this high energy rifle defense ammunition normally leave within one business day.

In a smaller rifle calibre see the Hornady Critical Defense 223 Rem 73gr FTX or the Hornady Critical Defense 223 55gr FTX. For a handgun, the Hornady Critical Duty 45 ACP FlexLock is built on the same thinking. Full ballistics are published by Hornady.