The average MIG gun for use with solid wire & gas will run smaller diameter F/C wires. A bigger diameter wire will require the use of a larger amperage rated gun, or just by increasing the liner size of the gas ready gun, providing it can handle the size you want to run. Lincoln uses a specific size input lug & can be purchased on a Magnum gun made by Lincoln, as well as many others. Tweco, Tregaskiss, etc. I would suggest looking on ebay for one, just measure the diameter of the socket the gun end fits into, so you can be sure of the right size on the gun you want to buy. Getting one from your local weld supply will most likely be expensive. I would look online first.

Good luck. S.W.

Hello fireboss108, I would only add a couple of other small items to Steve's great response. If you already have an extra gun from some other application they do make adapters that can be installed into the LN-25 and adapt it to other manufacturers guns. Certainly consider the amperage limitations of whatever gun you use or select. If you have or select a gun that is designed for use with gas it can double for the self-shielded as well as shielded wires, if it is designed to operate with self-shielded specifically you can't adapt it to use gas. Also consider wire sizes and liner sizes, you typically don't want to use a gun with a liner designed to run a large diameter wire with small diameter wire, in an extreme instance the small diameter wire can actually fold over itself inside of the liner and leave you in a real bind. Check with your local welding supplier to see what the various combinations are that can be used and make your best choice. There are relatively clean ways to adapt systems for guns on LN25's and there are certainly some real Lu Lu's. If you currently have a wire machine in your shop that you use on occasion and the LN25 that you got falls under that same sort of category then using an adapter might be a decent way to go. If you use both these relatively often and don't want to have to worry about taking the extra time to disconnect and restring the gun then finding another gun is probably the way to go. Good luck and best regards, aevald

The only problem with one gun for every thing is that mig guns in the 300-400 amp range only go up to .045 wire.  If you are going to run big flux-core wire .068-5/64 then get a flux-core gun they have a heat shield for you hand and a mig gun does have a long enough nick and will not stand up to the heat.  Been there done that.  Ram welding Supplies www.ramweldingsupply.com  has Tweco 400 amp mig guns for 152.00 at you door.  The part number should be "TWEWMK40153545L" but bubble check to make sure.  I got one last month and only difference between it and the 280.00 one at my local welding supply is the color.