porting and muzzle brakes

[Heavyhaul]

Can someone tell me the difference?  My understanding is that one is removable the other not.?  I also heard something about an "expansion chamber".  What might that be?  Till this is over, Graybeard will be charging me.

[KN]

To my way of thinking they both serve the same function basically. Porting is done to the barrel itself while a break is attached to the barrel. Some breaks are adjustable in that they can close or choke the ports such as the boss system that is suposed to reduce harmonics in the barrel. Where ports are to reduce upward muzzle flip. They do not reduce recoil but rather redirect it.   Hope this makes sense.   KN

[gunnut69]

Muzzle brakes have ports and barrel porting acts as a muzzle brake. Ports are simply put holes in the barrel or muzzle brake. They release high pressure gases in a jet to redirect or slow the recoil of a weapon. Muzzle brakes usually mean a device affixed to the end of a barrel using ports to reduce the recol effect. The brakes cut into the barrel itself do muddy the waters some. Most such as the MagnaPort are recoil reducers.. Some shotgun porting and 22 rimfire porting (and brakes) are really poor at recoil reduction and are more often a means to lower gas pressures at the muzzle which can disrupt the bullet or charge. There are other devices which can be attached to a muzzle that also manipulate cartridge gases. These are the flash hiders. As the name indicates their purpose is different. They try to alter gas flows to narrow or minimize the flash of the weapons firing. The expansion chamber you spoke of is usually found in muzzle brakes/flash hiders attached to the front of a barrel. They are simply enlarged areas the bullet passes thru that allow the propellant gases to expand. Since the pressure is thus lowered the gas pressure is reduced at the muzzle. This reduces dissruptions of the projectile as it transitions from the barrel to free flight. These chambers (numbers vary from 1 to several) also allow gas to escape and that which is not vented is greatly slowed.  The ports on those brakes with expansion chambers are usually much larger as the gas pressure is much less than it would be if not allowed to expand. These seem to me the most effective of the muzzle brakes and extreme versions are found on weapons that truly have to be braked such as the various 50BMG rifles and large cannons.

[Heavyhaul]

I guess that I had pretty much the right idea behind it all.  Thanks.  Gunnut mentioned the 50 BMG.  I shot a custom 50, I don't recall the manufacturer, but it was a single shot, "Shorty" model.  I was testing loads for my 30-06 and 243 that day, and the owner asked if I would like to give the spinner at 200 yards a couple of whacks.  Well, you know.  That gun had LESS recoil than my Rem 700 243.  Awsome brake.

[KN]

I took a 15" Encore barrel in 45/70 and cut it down to 10" for a project and with full power loads I could not hit the side of a barn with it because the recoil/muzzle jump was so bad. The barrel would literally "brush" my hair when  fired it. I added two sets of ports at the last 1-1/2" of barrel, one row at 45deg from top, the second set at 90deg from top and angled back 10deg. These were 3/16" holes a total of 18. Nine on each side. Now I get almost no muzzle jump to speak of, but it does redirect the recoil into the palm of your hand. I can now shoot about 5" group at 50meters with open sites. Whch is pretty good for me.   KN