Muzzel Brakes to be tested.

[Atomicdog]

oldmanjeffers - when you say you had the Ross brake opened up to BM specs, what were/are those specs. I understand the threads are 11/16X24...but what is the bore diameter? did you have your brake over bored?

thanks in advance!

[oldmanjeffers]

Atomicdog, Yes 11/16x24 on the threads and I believe the ID is .472, I'm not at home at the moment but will post what Ross had bored it to when I get back tonight.

He makes these for many different calibers so I just asked for the plain Jane brake for the 450 bushmaster and he sent out my beauty directly!

[Atomicdog]

Thanks for the info. I'm happy to hear that ordering it was that easy for you and you're obviously pleased with the work. Let me know your thoughts on its effectiveness vs. the brake supplied by BM. I'm definitely interested in the results. Thanks again.

[wildcatter]

Rule-of-Thumb is, .012" over the dia of the intended bullet..t

[slash2]

I tried out my new Ross brake Sunday. First off, Ross is great to deal with, the brake is beautifully machined and he had it to me within a couple of days of placing my order.

Now back to trying it out. I took the first three shot with the Izzy brake in place just to calibrate my shoulder, then I switched to Ross's brake. I notice a somewhat softer shove to the shoulder and a ton more muzzle blast to the sides. The folks on either side of me noticed the change too! I can't really say whether the rise was much different or not, I suspect not.

The biggest surprise to me was that my point of impact was 8" lower at 100 yards than the first three shots with the Izzy brake. I was shooting 240 gr XTP/MAG with 38 grs of lilgun. Three shots, Ross brake, nice group for open sites, all about 8" low. So I switched back to the Izzy, 3 shots, back up with the first three.

I don't understand why there would be such a difference in POI between the brakes. I wish now that I had fired off three with the barrel naked, no brakes, just to compare.

[Hoot]

I have muzzle brakes on all my heavy caliber rifles. Every functional muzzle brake I ever used resulted in lower POI's.

In the case of Ross' brake, it adds weight to the end of the gun, possibly changing the harmonics and reduces the tendency to flip. An interesting comparison would have been to also shoot without either brake in place for a control. Real brakes divert gas. That's how they reduce the rocket effect. If a brake does not divert gas, it will not significantly reduce recoil or flip. That having been said. Fat bore rifles with fast burning powder are probably at the bottom of the list for rifle types that benefit most from a brake. So in the case of the 450b, if it works at all, that's a strong testimony to it's effectiveness.

I'm not ripping on Bushmaster for no good reason. They make a great rifle. I just resent putting accessories on guns for the sake of eye candy. All they had to do to that flash hider was weld a flat washer on the end with a hole ~.010 over bore and it would have made a good brake. Folks with flash hiders have been doing that for a while to turn them into a brake.


Flash Hider:


Izzy:


Brake:


You be the judge...

The closer the size of the hole on the end to the bullet's diameter, the more effective a brake will be as it lets the bullet pass without gasses leaking around it until it's clear of the hole. Those microseconds from when it enters the hole until it clears the hole is the time when the path of least resistance for the gas is sideways. That's also why brakes with multiple constriction chambers or baffles are more effective. Each transition through a choke point diverts more gas. If like in a flash hider, there is no resistance to the gas blowing past the bullet during the time when the sideways exit is available, not much gas will go sideways. Some will, but most just continues forward with the bullet. There is a lot of good reference material on this subject available online, including hyper-speed photography showing what I just said.

Hoot

[MOUNTIN DU]

Pulled my forward gas block & izzy comp today. they both came off with no effort at all. i'm gonna have a blank (thread protector) made to replace the izzy comp during hunting season. i dont have a prollum with the recoil so a flash hider/comp is really not necessary and a comp tends to intensify the flash vertically which in low light hunting conditions can be a detrement to a fast followup shot

i might have the washer added while its off; as mentioned above by Hoot, just to see if it makes a difference

[gunnut]

I don't think the IZZY brake was intended to reduce recoil at all. It does an excellent job of reducing muzzel climb. Our tests proved that. Putting a washer on the end of the IZZY would only reduce muzzel climb more, Which is not really needed. You would be coming back UP to get on target. In order for a brake to reduce recoil it would have to redirect the gas to the rear. The IZZY can not do this. The POF did a very good job of this. But,was a good bit louder! Redirecting the gas at 90 and 360 around the muzzel does little for recoil or muzzel climb.
just my 2 cents worth.

[MOUNTIN DU]

so-o-o-o... i'm not thinkin' too far "out the box" by removing it for hunting purposes and reinstalling it again in the off season?
i'm even more curious about POI change with the gas block & izzy removed. just wondering

[bushmeister]

:? so-o-o-o... i'm not thinkin' too far "out the box" by removing it for hunting purposes and reinstalling it again in the off season?
i'm even more curious about POI change with the gas block & izzy removed. just wondering

From what I remember, the POI did not change at all between the Izzy, and nothing... and no, you wouldn't be thinking too far out. The sound levels were slightly lower w/o the izzy as well. You should definitely cover the threads as you mentioned so they don't get buggered up by all those antlers when you drag em out .