What steel for a 308 muzzle break?

[Tokarev]

I am designing a break for M14 that will be finished in parkerizing or blued.
What steel rods should I order? Are the breaks heat treated?

I have some FN-FAL breaks, they are most likely stainless painted black. So no help from them :???:

[Ronbo256]

I see no one has answered, I would probably use 4140 or 4340 chome-moly steel. 8620 would be good also. I would not bother to heat treat a muzzle brake.

[KCSO]

I use 4140 and don't heat treat.

[Lefty SRH]

4140 and no reason to heat treat.

[John Taylor]

I use 4140 annealed with no heat treat. 416 for SS brakes

[Nobade]

I use 12L14 or 1144 for blued brakes. They don't need to be hard, they hold up just fine. Aluminum doesn't last very long though.

[MtGun44]

Muzzle BRAKE. ;-)

4130 is readily available from aircraft suppliers like Wicks Aircraft in Highland, Ill. near St. Louis.

Great choice, heat treat not required.

Bill

[Moondawg]

Why not use an old chrome moly barrel. get an old shot out varmit weight barrel, so that you have some extra metal to play with. You have enough metal to make several brakes. You know the metal is proper barrel steel, you already have a straight hole through it, and you can probably get such a barrel for free or almost so from any gunsmith that does barrel work. I have made barrel tuners from old shot out BR barrels and a buddy has made muzzle brakes and flash supressors from old barrels.

[Nobade]

Sure, it works fine. Whenever I need a large diameter brake I use the cut-off back end of a barrel blank since I have tons of them laying around and don't have to buy a big chunk of steel to do it.

4140 or other chrome moly is fine if you are making just one brake. It takes too long to machine and is too hard on cutters if you are running off a batch of several hundred at a time.

[jmsj]

Tokarev,
I have used 1018 to make a "Miculek pattern" muzzle break for my daughter's mini-14 and it has held up well. I would imagine the harder steels would be more resistant to getting scratches and such but the 1018 is easier to machine.
Good luck.

[jimwill48]

12l14

[Tokarev]

Muzzle BRAKE. ;-)

I know, but my fingers type faster than brain thinks. Took typing course at high school.

[Jeff Michel]

12L14 Leaded steel, machines like butter, excellent finish and hot blues perfect. And cheap, just a bit more than 1018

[MtGun44]

Me too. ;-)

Bill

[John in WI]

I've never built a muzzle brake, but 4140 is whats often used for forklift forks. I built an anvil from a chunk of it once, and even un-heat treated the amount of abuse it can handle is amazing.

[Tokarev]

Now that I can't find my old thread about M14 hider thread size, I'll ask it here.

What is the drill diameter for .595 or 19/32-32tpi thread? Can't seem to find it anywhere.

[Reverend Recoil]

Use a main bearing cap bolt from a HD gasoline truck engine. They are made of tough material. You may have play around with tool bit geometry, cutting steeds, and coolant to get a good surface finish.