What grade of steel would I need to stop Magnum rifle rounds on the range? I know they exist, just don't want to pay that for completed targets....want to try and build them myself...

I know there are some metal experts like USMC and others on here.... help needed

Not steel but I've seen two walls of railroad ties 6 feet apart with sand in the middle work real well. Maybe a sign out front that says Clean fill dirt wanted too? What do you plan on placing in front of the steel to shoot through? Post what you decide to do, I'd like to know for future reference. Most leases I've been on didn't have a suitable place to shoot so it would be great to build something to check zero etc...

Regular carbon, but AR grade is what the military was using 10 years ago on the light weight vehicles. At 100 yards, a 7 mag will go through 1/4" though.

Here is what one target company says:

We Offer the Highest Quality Steel Targets Available
Most of our competitors only offer targets suitable for rimfire, but here at Metal Spinning Targets, we offer a full selection of targets including rimfire, centerfire handgun (magnum) and rifle grade (high-velocity). Our rifle grade high velocity targets are laser-cut from 500 Brinell grade steel to withstand centerfire rifle calibers, as well as lesser calibers, like .22 and handgun loads. Our targets are made of the same grade of steel used in dump truck beds and armored Hummers. This virtually indestructible steel when used properly will ensure you can continue using your targets for years to come.

http://www.metaltargets.com/AboutOurTargets/TargetRatings.htm

Our Guarantee
If you shoot any caliber closer then 25 yards you may be hit with bullet splatter.
If you shoot any rifle calibers closer then 100 yards the target will be damaged.
If you use steel core ammo or belted magnum rifle calibers the target will be damaged.
If you do not paint and lubricate your target's moving parts it will rust and will stop functioning properly.

Steel selection: The A.R. steel is 3/8” thick, rated at 500 Brinnell, and will withstand all handgun rounds. The Armor Plate is also 3/8” thick and is recommended for long guns at ranges exceeding 100 yards. If the long guns are to be used inside of 100 yards, 5/8” Armor Plate is recommended.

http://www.targets.net/html/steel_targets.html

Thanks guys... I am looking to build some reactionary targets, pop-ups and plates and the like for the new training range...

O.K. thanks I misunderstood, thought you were looking for a backstop. Shoulda known knowing you it would be more tactical. Sounds cool.

Thanks man! Actually have just got a dozer guy to redo backstop and add a new one, hence the need to do as much as possible ourselves....

Vernon 3/8" steel is what I use for mine. I use 6" angle for handgun and plate for rifle. I believe 3/8" is supposed to stand up to a belted magnum or a 22 center fire, which are supposed to be the cartridge class that punch thru regular 1/4" targets.

Look in to Mil-A-12560 or Mil-A-46100.
I have been building sub components for armored vehicles for the D.O.D. and these are the grades I have been using.
Thicknesses I have used range from 1/4" to 1/2".

http://www.chapelsteel.com/

look at what they offer - they do plasma cutting. I buy from them from time to time. AR500 is hard to come by right now. From what I here the goverment has most of it tied up with the military.