Having never shot at steel plates before, or even seen one for that matter, I was wondering what type of steel I would need for 300-400 yard plates. I would be shooting them with a 7mm RM loaded with either Hornady 139gr SST's or Nosler 140gr BT's, both at about 3200-3300 fps.
I was thinking of maybe six or eight inch round plates to simulate the kill zone of a whitetail (Southern Alabama whitetail deer that is. Kinda small. Maybe should be three to six inch plates...hmmm)
Regardless, if anyone could share their knowledge on this, I would be grateful.
The steel I shoot is 3/8" Brinnel 500 rated. A steel shop should be able to get AR400 or AR500 steel for you. AR = Abrasion Resistant and the nuber rating as I understand it is the hardness rating.
The problem is going to be the velocity from the 7mm RM, high velocity rounds go through some pretty hard steel so you may need to move the steel further out or shoot a heavier bullet.
With the 3/8" 500 Brinnel steel we can shoot for years with 308's and 168's & 175's or use the big magnums and heavy bullets and never burn through BUT a hot loaded 300 Win mag with 180's will burn through at 250 yards. A hot loaded 338 Lapua with 200 Ballistic Tips will burn through at 350 yards.
Mild steel give a less resounding "gong", hard steel a little nicer in the reply and can be heard better from further distances or on windy days.
Ian M reports that by angling the steel so that the round strikes an deflects into the ground helps prevent burn through (and shrapnel too I'd imagine).
Have you ever tried welding 3 3/8's thick plates together? Ive shot at mild steel that was a 1.25 thick and with a 7mm STW. Of course at 100 yards youll do some impressive damage but when you get out to 500 yards its a nice SMACK sound. Give it a shot and see if your loads do any damage to it.
Well, leaving them out in the field isn't an option, as their are vandels and thieves living within driving distance of the area where I would be shooting. That was part of the reason that I want them to be somewhat small. Also, I don't have a trailer to haul with either, but that idea of hanging them off of a sawhorse sounds good, because I could fit a disassembled saw horse in the back of my truck (Bronco 2, fairly small if you've never seen one,).
What I may try is welding a couple of pieces of 1/4 together and angling them a little like Ian M. suggests, and just seeing what happens. I think I can get a few scrap pieces of 1/4 for free, so if they act like wet paper, all I would be out is a little acetalyne.
Thanks for the info everyone, when I finally get it done I'll let you know how it turns out.
We shoot two different sizes of steel for two different purposes. The smaller square plates, ranging from 6x6 to 15x15 inches are just plain to hit out at 700 and longer and they are about the size of the vital area of a critter or smaller. The big 40x40, 24x48's and others are nice for getting initial drop settings as we can walk the group into the center of the plate for a zero. Bullet impact location is easy to see at long range through the scope or a spotter. They are also used for shooting groups as we can get a rough measurement from the center of the bullet splat, there is always a neat black spot at impact. Not as good as paper but still good enough to tell a 5" group from a 6" group out there.
You could pick up some cheap sawhorse hinges and five pieces of 2"x4" (four legs and a center piece) and some chain or poly rope, that is all you need. We use "S" hooks through two 1/4 or 1/2 inch holes at the top of the plate to hang them with. Shrapnell will cut polyrope, light chain is better and get extra because you will eventually cut the chain with a bullet.
I would even try to hang two or three pieces of steel one behind the other without welding them, should be quite a commotion happening when you hit the front one.
First, there are two considerations. Are the plates left on the range or field or do you have to remove them and travel with them. Obviously traveling with big sheets of 1/2" plate is ugly. We have to do that and have started to use a wheeled dolley to move them with, saves the back. Have an old boat trailer to haul all the damn steel on. Can even drag it out in a pasture if necessary if we can't drive off trails.
I shoot steel a lot and have changed my attitude towards my steel plates. I have some big plates for long range, 1/2 mild steel cut 30x30 inches and even bigger. Also have some .375" mild steel at 40x40 which is nice for catching bullets. Now I am leaning towards 2x4 foot pieces of 1/4 inch steel. Much easier to handle but they get beat up and perforated. Nice to keep them in good shape, don't dimple, gouge or punch them but what the hell, steel is NOT expensive and so what if you blow some holes through it or bend it into a bow.
We are using either old swing sets or simple saw-horses made with old 2x4's and 5 dollar saw-horse clamps to hold the steel - both are light and dirt cheap. My buddy just bought a pretty good swingset at a yardsale for $1.00.
I believe our next "test" will be hanging two or three pieces of 1/4" or 3/8" plate in tandem to see how much noise they make when hit. Also know some guys who are shooting old discer blades.
If you don't mind it being all dimpled up good, the 308 win at 300yds 2600MV with Failsafes left pretty good goosebumps on the backside of 1/2" mild steel and a little bigger on the 3/8".
I would get T-1 steel if using it that close or with higher power cartridges. I just got a 15"x20" remnant of T-1 last week and am going out tomarrow with the 300WM at 300yds with the new Nightforce to sight in. They said it was WAY harder. They didn't even want to put the 4' long piece in the shear so I could fit it in the car but he did. He said it would dull the blades if they did it too many times so they don't. I don't know what hardness it is though.