Welding AR500 Steel Plates

[esrice]

To weld or not to weld, that is the question!

This issue was discussed recently in another related thread ( https://www.indianagunowners.com/forums/shooting_sports/103903-homemade_steel_targets.html ), so I thought I would bring the discussion over here.

It appears that there is some controversy over whether or not welding AR500 plates adversely affects their integrity.

Now, I am not a steel worker, and have no practical knowledge of its properties. I do, however, have some experience in shooting AR500 targets.

While researching various targets in the past I've commonly read on manufacturer's websites that welding AR500 is not recommended due to the heat involved in the process, which would 'weaken' the steel, and reduce its hardness.

Here is an example: MGM Targets | FAQ

One of the most misunderstood, or overlooked factors impacting target life is heat. Virtually all target steels in use today are "quenched and tempered", meaning that at the time they are rolled (at the mill) they are heat treated. The chemical content of the steel certainly plays a big roll in target life, but any heat applied after the mill heat treatment will adversely affect the life of your targets. This stuff isn't mild steel, so you can't treat it as such.

There are some manufacturing processes that affect hardened steel during fabrication. The first thing that comes to mind is the cutting process. The hardened steels cut nicely with an oxy-acetylene torch, but the heat that is put into them when the torch travels at 30-40 inches per minute is great. We cut all of our steel with a high definition plasma, laser, or water-jet. The heat affected zone is minimal, basically only at the extreme edge of the target. You'll never notice it under pistol fire, but it can be seen to an extent when you begin to hit the edges with high power rifle rounds.

When you weld on any heat treated material, use multiple small, hot beads, rather than a large one. The object is to limit the amount of heat you put into the steel as much as possible. Let the first weld get cold enough to touch before you make the second pass, or before you make a pass on the other side. This will minimize what is technically called the "heat affected zone", and consequently minimize the amount of temper that is removed from the parent material. Heat on mild steel has very little effect on it, but it is critical when you are working with heat hardened steel.

I'm curious what other INGOers think, especially those who may be involved in the steel industry. Personally I wish it was able to be welded, because this would solve some of the issues with hanging our steel targets. However, with the warnings against it by the manufacturers, I don't feel confident in going ahead with it.

 

[bigcraig]

I think it depends on where on the target you are wanting to weld.

For example, if you want to make a popper type target you will only need to weld on the very bottom to affix the hinge type of your choosing. And if you take the advice from your second quoted paragraph and only use quick small hits with your welding device and wait between beads or spots you should be GTG.

What method are you wanting to use to hang your AR500 targets, or a better question, where on the target are you wanting to attach your attachments?

 

[groovatron]

Spot welding on the back of an AR500 target is fine IMO. It may not be the best way, but it can and has been done. I'm sure "overdoing" the weld will have a more negligable affect. This isn't a structural weld and you don't need 5 passes. The guy that welded his target in the thread where this conversation began, had no idea what he was doing. As your quote suggests, if you are going to weld on AR500 and want minimal stress, spot weld it. I would be curious to do an actual test on these plates. I have only shot steel and have no experience with it's longevity, maintenence, and durability. Definitely an interesting topic. I would bet that the manufacturer puts this disclaimer on their product for warranty and liability. Just like gun manufacturers state to never carry a loaded gun in their pamphlets lol.

As far as my qualifications.........I am a professional welder. I specialize in GTAW, mailnly aluminum. I mostly work with custom light duty fab jobs. My current job does not require AWS certification, but I have been in the past and have also completed college level programs.

 

[downzero]

Welding AR500 plate defeats the purpose of using it. I would drill it and tap it if I had to, but under no circumstances would I make any weld of any serious size on a piece of armored plate unless I intended to have it heat treated again.

It's not mild steel.

 

[esrice]

What method are you wanting to use to hang your AR500 targets, or a better question, where on the target are you wanting to attach your attachments?

Haven't got that entirely figured out yet.

Plan is to have a few stands made to hold the small IPSC plates at 30 degrees, similar to this:

Another possible configuration would be a dueling tree.

 

[cornfused]

It looks to me that you could make those stands in a way that you could slide the target down into a couple pieces of C-channel or angle and have them hold it in place (both sides and bottom). That would make it easier to brake down and not require any welding on the ar500.

 

[esrice]

It looks to me that you could make those stands in a way that you could slide the target down into a couple pieces of C-channel or angle and have them hold it in place (both sides and bottom). That would make it easier to brake down and not require any welding on the ar500.

You've probably got the right idea.

The part where welding would come in handy would be for the dueling tree.

 

[IndyMonkey]

Weld them, shoot them in the welded area. Report back.

How hard is that?

 

[esrice]

How hard is that?

So easy a monkey could do it.

 

[IndyMonkey]

So easy a monkey could do it.

I will too if you want me to on Monday.

Let me know

 

[Field King]

If u are welding around the edge u probably will not need to worry, while these areas are hit with shots they do not take the most hits, heat does affect the steel target, that is why AR500 armor is used, it is designed to withstand more abuse than mild steel! The impact of the projectile is what ultimately affects the steel, including the heat created by the impact which will eventually deteriorate the surface from repeated hits! Some manufactures may overstate the impact of welding AR plate in an attempt to warn users of the dangers involved as welding will advance the deteriorating process in the area of the weld. This is mostly due to the fact that milder steel is usually used to weld to the AR as frame supports, stands etc. As a side note, the acronym "AR" stands for "abrasion resistant" and not "armor" so one must understand that the material is only "more" resistant to impact as compared to milder grades of steel, there is another grade being used currently with great results that I am sure will be appearing soon on the wider market that surpasses AR plate in durability for steel target use! I hope I have not added confusion but will part in saying safety is of the utmost importance with the use of safety shooting glasses, safe/predictable splatter zone and safe distances being a few that come to mind!

 

[mwilson]

Haven't got that entirely figured out yet.

Plan is to have a few stands made to hold the small IPSC plates at 30 degrees, similar to this:

Another possible configuration would be a dueling tree.

if you mount them solid like this will the target be effected in anyway? with them hanging it seems like the target swing will absorb some of the shock. or will the bullet from a .308 just splatter when impacting the steel when mounted solid.

 

[esrice]

if you mount them solid like this will the target be effected in anyway? with them hanging it seems like the target swing will absorb some of the shock. or will the bullet from a .308 just splatter when impacting the steel when mounted solid.

In the pictured design, you want the steel semi-static and to remain at a constant 30 degrees-- that way you have a consistent downward splatter.

I just posted the pictures to help answer bigcraig's question. The main point to this thread was whether or not INGOers thought anything should be welded to AR500.

 

[Field King]

In the pictured design, you want the steel semi-static and to remain at a constant 30 degrees-- that way you have a consistent downward splatter.

I just posted the pictures to help answer bigcraig's question. The main point to this thread was whether or not INGOers thought anything should be welded to AR500.

esrice, what is your objective? To determine the durability of the target after welding? The safety of continuing to use the target after welding? Or?

 

[ReadnFool]

I checked a while back and the AR150 steel had almost twice the manganese (added for toughness) as the AR500. AR500 also had higher carbon. AR500 is quench and temper while AR150 was not. This tells me that the bulk of the toughness in the AR500 is solely because of the heat treating. This means that even small amounts of heat can turn it back into mild steel in the area heated.

 

[esrice]

esrice, what is your objective? To determine the durability of the target after welding? The safety of continuing to use the target after welding? Or?

Reading the link in the OP might help with some background.

Basically, a guy welded a hollow pipe to the back of a piece of AR500, to aid in mounting it to his stand. I've always heard that welding anything to AR500 was not recommended. Some folks didn't agree, so I thought I'd bring the question here to its own thread, to get a broader sample of answers.

I am curious if welding would affect the overall integrity of the plate to the point where it became less durable or unsafe.

 

[cornfused]

I have used something similar to this and it might help in your case also.

HOT STOP SPRAY 16OZ [MTS7100EACH] - $11.47 : Auto Tool Source, Your source for tools


The guy that demonstrated it to us held a 7/16 x 4" bolt on one end, sprayed this stuff in the middle and heated the other end with a torch until it was glowing red! So it would help minimize the affected area for you. But I do think that welding on the edge would be my only option.

 

[Field King]

Reading the link in the OP might help with some background.

Basically, a guy welded a hollow pipe to the back of a piece of AR500, to aid in mounting it to his stand. I've always heard that welding anything to AR500 was not recommended. Some folks didn't agree, so I thought I'd bring the question here to its own thread, to get a broader sample of answers.

I am curious if welding would affect the overall integrity of the plate to the point where it became less durable or unsafe.

I would say it will be less durable in the welded area, the weld will not be hot enough to re-treat the whole target unless it is a very small target, then again there are so many variables such as the "Brinell" hardness has been reduced in the welded area but not overall etc. I would first follow basic safety rules that would be used for any steel target regardless of durability, such as a predcitable splatter zone, high quailty back stop, safety gear worn by shooters and bystanders, now with that said we are into the simple durability factor which affects cost of targets, length of life/use etc. Remember these targets are usually plasma or flame cut which are very high heat cutting processes themselves, very few if any are water jet cut! This in itself may be the hint we are looking for?

 

[groovatron]

Interesting article relating to this topic.

Welding's effect on strengthening steel - Metals/Materials Tech Cell - TheFabricator.com

 

[esrice]

Interesting article relating to this topic.

Welding's effect on strengthening steel - Metals/Materials Tech Cell - TheFabricator.com

Thanks for the link!

Looks like it was recommending a post-weld heat treat if one were inclined to weld at all, due to possible damage to the "heat affected zone".