Before my eyes went, I was a competitive Metallic Silhouette shooter. My bolt action pistol is chambered for .308. I know that a .308 round will blow right through 3/8" hot rolled, yet the bullet would not even leave a mark on the T1.
The targets were purchased and all anyone knew was that they were "T1 armor plate". I also know that the welds where the feet attached were very weak and frequently broke.
Anyone have any idea what this alloy is?
Thanks, John John DeArmond
Tellico Plains, Occupied TN See website for email address
T-1 is US Steel's old trade name for A514 high-strength, low-alloy (HSLA) structural steel. HSLA steels -- there are several -- are formulated to have fairly high strength (typically twice the strength of common low-carbon, hot-rolled or cold-rolled steel) at low cost, relative to traditional alloy steels. Most HSLA grades also are designed to have fair-to-good ductility, allowing them to be bent and formed without tearing. Auto-body sheet steel is of this type today, and has been since the early '80s, although there are even more advanced types now than common HSLA.
Armor plate is one of the common uses for A514. If you want to see the specific alloy makeup, it's available here:
There are specific instructions for welding A514. You can find them on the big welding-equipment manufacturers' websites, or other welding websites.
Some other high-strength steels you might be able to buy locally in small quantities are RQC and AR400 thru 500. They are used to repair worn construction equipment. Truck leaf springs are good stuff too. You need a chop saw, plasma cutter or acetylene torch to cut them, they ruin a metal-cutting bandsaw blade.
RQC tends to be warped. I found out the hard way that welding high-strength steel can harm the properties of the heated metal beside the weld, such as make it extremely brittle.
I am a 'retired' target maker. Gave it up and then got calls...
A500 series is really tough stuff. A400 is spec by NRA and IHMSA for Big Bore rifle and pistol.
A500 is even better than 400 - BHN numbers ... 308 at 50' dimples 500, but 400 it dents.
I use A500 material for Double Buck, big bore pistol and hot rifle. I normally get AR500F and AR500.
AR500 / AR500F AR500 and AR500F are quenched & tempered through hardened wear resistant grades of abrasion resistant steel plate used for severe impact and abrasion. Chapel Steel's premium grade of these products are Chapalloy
500 and Chapalloy 500F. Chapel Steel recommends the ?F? chemistry in applications where there will be forming or higher impact.
Mechanical Properties: Tensile: 247 ksi TYPICAL ? NOT INTENDED FOR STRUCTURAL USE Yield: 187 ksi TYPICAL ? NOT INTENDED FOR STRUCTURAL USE Elongation: 11.1% in 8? Brinell: 450 min / 500 nominal
A514 Picture of a excavator. A quenched and tempered high strength steel used in structural applications where high strength and low weight are critical. We stock this material in Grades B, H, F & Q.
Mechanical Properties: Tensile: up to 2.5? 110 to 130 ksi over 2.5? to 6? 100 to 130 Yield: up to 2.5? 100 ksi min over 2.5? to 6? 90 ksi min Elongation: up to 2.5? 18% in 2? over 2.5? to 6? 16% in 2? Brinell: 235?293 is typical, but it is not usually indicated on the MTR?s
Grade: Grade B: Up to and including 1-1/4? Grade: H: Over 1.25? to 2? inclusive Grade F: Over 2? to 2.5? inclusive Grade Q: Over 2.5? to 6?
T1 is lightweight compared to 500's. T1 is T1-321/360
Mart> Before my eyes went, I was a competitive Metallic Silhouette shooter.