Muzzle brake for 300 Weatherby Mark V

[VenatusDominus]

I am having trouble deciding what the correct move is for a muzzle brake for my 300 Weatherby Magnum, Mark V, bought circa 1980. To start with, the outside diameter of the barrel at the tip is .610. I believe this means that I need to find something with a 1/2 by 28 thread. Otherwise I would have to shorten the barrel to a point where a 5/8x28 would work which was the recommendation from a local gunsmith.
.
Secondly, Weatherby only cells one type of break with portholes around the entire diameter, which makes it difficult for prone shooting if you don't like a mouthful of dirt. I have also heard of CSR brakes but don't know much about them. I have questions on whether a 1/2x28 is safe to use or not. Does anybody have experience with adding a break to a Weatherby?.

I have a 300 Weatherby Mark V synthetic stock with a slim 24" barrel I purchased new in 1991. In Dec 2020 I sent it to the factory to have the muzzle threaded for a brake (total cost with shipping was $241.92, that included the factory brake and a screw-on thread cover for use when the brake is off the gun). The slim barrel required 1/2x28 threads. I had to purchase the factory radial brake to not void the factory accuracy warranty. As soon as I received the rifle back from the factory, I swapped the factory brake with the PA Hypertap below. The Weatherby break is rated at 54% recoil reduction and the PA Hypertap is rated at 84% recoil reduction.

​ 1 x Precision Armament HYPERTAP Muzzle Brake Slim 7.62mm/.308Cal, 1/2-28, Black, 7.62mm/.308, A04614​

I spent 6 months working up hand loads for the gun and could never get it to group less than 1.5" at 100 yards with the Hypertap. The felt recoil reduction was in the range they claimed at 84%. I put the factory brake back on and the felt recoil was greater, but about what Weatherby claimed at 54%. Yeah, the radial brake is not ideal when shooting prone, but with the factory brake the gun regularly shoots 0.3" groups at 100 yards, providing I do my part. The Hypertap brake is definitely better at mitigating recoil, but the loss in accuracy was not an acceptable trade-off for me. With the Weatherby brake, the gun is now enjoyable to shoot and still very accurate. Plus the factory brake matches my blued barrel perfectly in diameter and finish, and unless you look very closely, you would think the barrel is ported and not that there is a screw-on brake attached. I think the size/weight of the Hypertap was just too much mass at the end of a very slim barrel, causing it to amplify barrel harmonics and whip about, adversely affecting accuracy.

 

[WYO300RUM]

I am having trouble deciding what the correct move is for a muzzle brake for my 300 Weatherby Magnum, Mark V, bought circa 1980. To start with, the outside diameter of the barrel at the tip is .610. I believe this means that I need to find something with a 1/2 by 28 thread. Otherwise I would have to shorten the barrel to a point where a 5/8x28 would work which was the recommendation from a local gunsmith.
.
Secondly, Weatherby only cells one type of break with portholes around the entire diameter, which makes it difficult for prone shooting if you don't like a mouthful of dirt. I have also heard of CSR brakes but don't know much about them. I have questions on whether a 1/2x28 is safe to use or not. Does anybody have experience with adding a break to a Weatherby?.

I have APA micro basterd on 3 sporter diameter barrels. They are 1/2x28 self timing.They aren't most recoil reduction muzzle breaks out there but they are just a little bigger than barrel diameter. I have on a 7mmRM, 300 WM, 257 Weatherby and even on a 300 RUM w/a varmint contour barrel . 9/16x24 micro .It's same diameter of barrel end.
Just a thought.

 

[WYO300RUM]

Hey, I also had a Gen 1 APA in 1/2 by 24 put on my original 300 Wby barrel. The recoil reduction was great. Barrel was toast about four years ago and it was replaced with a carbon 6 in 300 Wby. New brake is a gen 3 five port APA. Recoil reduction is awesome
Take Care

I had my original gen. 1 APA micro basterd on 300 RUM blew a peice out of the web between ports. They sent me a new gen. 2. He said the had problems with being to thin there. My other 3 at Gen 2 also. No problems. Their customer service is great . also.

 

[woodsman1991]

I'll also recommend getting one of the factory brakes, they did a decent job designing them.

 

[coueskiller43]

I agree with other posts about the factory brakes. They greatly reduce recoil but are obscenely loud (seem to be louder than a side port brake). If you want a gunsmith to install it send it to Karl at Kampfeld customs. His brakes are very similar to a factory weatherby brake. He does excellent work. It's difficult to see the seam between the barrel and brake when he's done with it.

 

[Idaho Lefty]

Patriot Valley Arms ( PVA ) did my "Sporter" barreled, Tikka, T-3 with, 9/16" X 24 tpi and Recrowned the Muzzle for $135.00 and I put their, Back Country 3 Port, Jet Blast Brake ( $125.00 ) on it to AVOID,.. the Concussion / BLAST to, the Shooter ! We now have 4 of them, in My Family !
Amazing,.. Recoil reduction and LOW amount of Muzzle "Jump", on my son's 7 PRC shooting 180 gr., ELD-M's at almost,.. 3,000 FPS !
My 13 y/o grandson is shooting My old, .270 WSM with, 140 gr Bergers, clocking almost, 3,200 FPS and can easily shoot, a Box of Ammo at Steel !
My son and I DID, a LOT of Research, before choosing, PVA Brakes. Yes, you might LOSE, 5 % of the total Recoil, reduction "Capabilities", BUT it's, Worth It, NOT to Hear, ALL, the "Concussion" at,.. the Shooter !!
The "Blast" is, "Re-Directed" thoughtfully at, a much BETTER,.. Angle !

 

[asd9055]

Here are three radial brakes. First two are custom made/installed by my local gunsmith. Last is WBY Factory. They all shoot great. I can handle the recoil, but why, if I have a choice?

 

[Window]

I am having trouble deciding what the correct move is for a muzzle brake for my 300 Weatherby Magnum, Mark V, bought circa 1980. To start with, the outside diameter of the barrel at the tip is .610. I believe this means that I need to find something with a 1/2 by 28 thread. Otherwise I would have to shorten the barrel to a point where a 5/8x28 would work which was the recommendation from a local gunsmith.
.
Secondly, Weatherby only cells one type of break with portholes around the entire diameter, which makes it difficult for prone shooting if you don't like a mouthful of dirt. I have also heard of CSR brakes but don't know much about them. I have questions on whether a 1/2x28 is safe to use or not. Does anybody have experience with adding a break to a Weatherby?.

Funny this post just pooped up. I shot with an old friend this morning who I was helping load for a new 30-378 Accumark however he brought his old 300wby vanguard to shoot as well. Our furthest target was at 670 and he was centering an eight inch plate with ease with his new rifle and has never pulled the trigger on anything past 200. He pulls out the old 300 wby vanguard and attempts to shoot the 250yd target with dismal results, so I ask him to let me shoot it and he spot the shots. Needless to say, I shot it once and handed it back to him stating there's no one who could shoot this accurately long range without it having a break on it. I have brakes on all my rifles and enjoy spotting my own shots and don't mind shooting with the best hearing protection I can afford. I also love shooting with cans, but I'm old school and don't have a tube under 26"s and they're not practical to use while hunting.

 

[2HuntinAK]

Funny this post just pooped up. I shot with an old friend this morning who I was helping load for a new 30-378 Accumark however he brought his old 300wby vanguard to shoot as well. Our furthest target was at 670 and he was centering an eight inch plate with ease with his new rifle and has never pulled the trigger on anything past 200. He pulls out the old 300 wby vanguard and attempts to shoot the 250yd target with dismal results, so I ask him to let me shoot it and he spot the shots. Needless to say, I shot it once and handed it back to him stating there's no one who could shoot this accurately long range without it having a break on it. I have brakes on all my rifles and enjoy spotting my own shots and don't mind shooting with the best hearing protection I can afford. I also love shooting with cans, but I'm old school and don't have a tube under 26"s and they're not practical to use while hunting.

Hello Sir, I was perusing the forum and noticed you had mentioned that you have some experience with .30-378 Weatherby loads. I would like to PM you to discuss but I don't have enough posts. If possible can you text or email? I can be reached at 907-575-5900. Thank-you for your time!

 

[A/1-61]

Funny this post just pooped up. I shot with an old friend this morning who I was helping load for a new 30-378 Accumark however he brought his old 300wby vanguard to shoot as well. Our furthest target was at 670 and he was centering an eight inch plate with ease with his new rifle and has never pulled the trigger on anything past 200. He pulls out the old 300 wby vanguard and attempts to shoot the 250yd target with dismal results, so I ask him to let me shoot it and he spot the shots. Needless to say, I shot it once and handed it back to him stating there's no one who could shoot this accurately long range without it having a break on it. I have brakes on all my rifles and enjoy spotting my own shots and don't mind shooting with the best hearing protection I can afford. I also love shooting with cans, but I'm old school and don't have a tube under 26"s and they're not practical to use while hunting.

Well let me give you an update. I purchased a radial muzzle brake directly from Weatherby, half by 28 thread and had a local gunsmith threaded the barrel. I reblued the barrel with a three steps process and it looks like the muzzle break was always part of the rifle . I have only put 12 shots through it and I'm getting 9/16 MOA groups. Prior to putting the brake on, I was lucky to get two or 3 in MOA groups. I believe I have eliminated 75% of the recoil. Now the next step is to get my Swarovski 3.5x18x44P (ballistic turret) tuned for my Utah hunt. My plan is a 340 yard zero. 53 clicks of adjustment should get me out to 910 yd. I have a 650 range on my Maine property and I'm heading up there next week to test this setup. I love when a plan comes together.

Funny this post just pooped up. I shot with an old friend this morning who I was helping load for a new 30-378 Accumark however he brought his old 300wby vanguard to shoot as well. Our furthest target was at 670 and he was centering an eight inch plate with ease with his new rifle and has never pulled the trigger on anything past 200. He pulls out the old 300 wby vanguard and attempts to shoot the 250yd target with dismal results, so I ask him to let me shoot it and he spot the shots. Needless to say, I shot it once and handed it back to him stating there's no one who could shoot this accurately long range without it having a break on it. I have brakes on all my rifles and enjoy spotting my own shots and don't mind shooting with the best hearing protection I can afford. I also love shooting with cans, but I'm old school and don't have a tube under 26"s and they're not practical to use while hunting.

 

[A/1-61]

Here is another update, the last and final one how about my 300 Weatherby Mark V. I've made a few changes and have found an even better node. I substituted my Winchester 9.5M primers for Federal 215 Magnums which I recently found at Cabela's. I just returned from the range. It is a bluebird day here, bright with the sun to my back, target crisp and clear at 100 yd, The five shot group below, calculates to a .397 inch group at 100 yd. It looks like two shots did (barely )hit paper at the left portion of the group. Again, I am using a 212 grain ELD- x with a COAL of 3.700. H1 000, 84.1 grains. 2994 FPS. The node is one thing, but the muzzle brake made the difference, controlled anticipation, without the negative expectation. First time I ever shot that rifle in a short sleeve shirt. Thank you to everyone that helped me out with this project. I am in awe of the wealth of knowledge that is conveyed in this forum.

 

[A/1-61]

 

[asd9055]

Nice work.

 

[AZShooter]

I am not going along with the other's suggestions in this discussion. I felt I should share what I found on this subject

I recently made a 338 RUM. I tried it without a brake and decided that this 10 lb rifle's recoil is a bit much. I began researching muzzle brakes.

I discovered that the barrel can actually enlarge its inside diameter if it is machined too thin for the threads.

Barrel End Threading — Bigger Diameter is Better « Daily Bulletin

Our friend Robert Whitley of ARX Enterprises LLC has learned, through careful measurement and testing, that some barrels threaded 5/8 x 24 TPI at the muzzle may not deliver optimal accuracy.

bulletin.accurateshooter.com

================

In addition to this there is a safety factor to consider.

Thanks for the advice from JE Custom:

There seems to be a lot of varying opinions on what size of barrel can or can't have a muzzle brake installed.

I am sure some will disagree and that's all right, so here goes.

After talking to barrel makers and engineers and using their recommendations for MINIMUM wall thickness I found that this was a rule that most were not willing to break 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.

Be safe

JE Custom

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After reading the two articles posted above, I decided my 338 barrel was too thin to thread. I did research into the Witt custom clamp on brake. I ordered one to fit my barrel's taper and an aircraft mechanic friend suggested I use Locktite 660 on the barrel instead of Witt's suggestion I use blue locktite. I did use blue locktite on clamp screws. The larger outside diameter with its five side ports on each side removed the unpleasant recoil. The clamp has not moved and I am happy with the results. It is not as elegant as some brakes but just like my trail horse beauty is as beauty does. My 338 RUM with 300 gr bullets is pleasant to shoot. In addition to this the price was reasonable and it was easy to install.

Custom Clamp-On Muzzle Brake - Witt Machine

Make your rifle more fun to shoot!!! Our Clamp on Muzzle Brakes are precision machined to YOUR exact barrel specs. Tapered, Straight, or Stepped, we machine brakes for them all. Because these brakes are custom cut to Your dimensions we can hold tighter tolerances on both the bore and bullet exit...

wittmachine.net