Question about using steel as a backstop?

[KQguy]

I got a hold of a piece of 1/4'' steel plate from a friend of mine,I am planning on using it as a backstop(it will be angled down so the bullets deflect into the ground).The other day I shot my 300 win. mag with 110gr. V max's at it from 100 yds,and it went through it like it wasn't even there!How far away can I use 1/4'' steel without the bullet going all the way through?I know the bullet probably doesn't go much farther after it goes through the steel,but I don't want to ruin my steel plate.

 

[NYLES]

My 270AM goes through 3/8 straight on at min 500! You need bigger steel! 1/2" (that prolly wont work at a 100) min plus that was a lil bullet think about hitting it a 180 grain!

 

[KQguy]

My 270AM goes through 3/8 straight on at min 500! You need bigger steel! 1/2" (that prolly wont work at a 100) min plus that was a lil bullet think about hitting it a 180 grain!

Yeah,I know.That's why I was so surprised that the Vmax went right through it,I thought they were suppose to come apart on impact.

 

[Reno]

My .308 will chew through 1/2 inch steel that is NOT armor plated at ranges up to about 600 yards, depending on the bullet I am using. If you want steel to stop a heavy bullet, it must be armor plated or extremely THICK, I currently use 1 inch thick steel and have no problems with it. I use old scrap steel I find in my travels. For a good backer, It'd have to be a armor plated steel I think to even have a chance of not passing through a 1/4" piece at less than 500, and I think that wouldn't quite be enough personally.

 

[Captn C]

7mmRM with 140gr Nosler BT's will burn though 1/2" out to 500. Those plates were hanging from chains though. Not sure if that would make difference.

 

[long ranger]

Velocity of the bullet and angle of the plate are the biggest determining factors.
We used 3/8 T1 plate for a backstop at a 100 yard range I built many years ago and it would handle almost every rifle caliber ammo except those with AP bullets, the angle was long, as in 30 degrees from the floor upwards , at the end of the plate was about a 16" curl back, so the bullets would slide up the plate and be spun back into it once most of the energy was dissipated, then the spent bullet slid back down into a trough for easy cleaning.