There seems to be a lot of varying opinions on what size of barrel can or can't have a muzzle brake
I am sure some will disagree and that's all right, so hear goes.
After talking to barrel makers and engineers and using there recommendations for MINIMUM wall thickness I found that this was a rule that most were not willing to brake for safety reasons.
After doing all of the calculations using this information this is what I came up with and use for all of my brake installations.
It is based on the caliber of the barrel and safe wall thickness remaining after threading. these dimensions at the muzzle of the barrel are "MINIMUM" for safely installing a muzzle brake.
.224 bore = .563 muzzle diameter
.244 bore = .584 muzzle diameter
.257 bore = .597 muzzle diameter
.264 bore = .604 muzzle diameter
.277 bore = .617 muzzle diameter
.284 bore = .624 muzzle diameter
.308 bore = .648 muzzle diameter
.323 bore = .663 muzzle diameter
.338 bore = .678 muzzle diameter
.350 bore = .690 muzzle diameter
.375 bore = .715 muzzle diameter
.400 bore = .740 muzzle diameter
.416 bore = .756 muzzle diameter
.425 bore = .765 muzzle diameter
.458 bore = .798 muzzle diameter
.470 bore = .810 muzzle diameter
.510 bore = .850 muzzle diameter
.570 bore = .910 muzzle diameter
.600 bore = .940 muzzle diameter
These dimensions are also minimum recommended wall thickness after fluting (Bottom of flute to bore).
There is some support from the muzzle brake depending on the quality of the threads, but I don't recommend relying on the brake to make up the minimum wall thickness. on very small barrels finer thread pitches are normally used because on thread height (The finer the thread the shorter the thread height, using less of the barrel wall thickness.
Also, as bore diameters increase more stress is placed on the barrel because of the larger surface
of the barrel wall.
This post is not intended to be the last word, it is just a guide line to help decide if it is possible to install a muzzle brake safely on your barrel.
J E CUSTOM