First Impressions: Without Warning – Tuner Muzzle Brake (TMB)

Disclaimer: As always when reviewing products I remain impartial. I have not been paid for this article. However; I did receive the TMB from Without Warning in a deal where I loaned two other brakes to BJ so he could compare them side by side with his product. The product I have been provided is a prototype and I will be given a production model when available.

Earlier this year while browsing around on Snipers Hide I came across a thread on rifle barrel tuners. I had heard of these devices before however I didn’t look into them much further; I figured they were more for the bench rest crowd. However looking further into it, I came across the Tuner Muzzle Brake or TMB by a bloke called BJ who just happened to be from Melbourne, Australia. Being a fellow Aussie it piqued my interest and I had a further look into it. The idea appeared sound to me: A muzzle brake and Tuner all in the one device.

Being a fellow Precision Rifle Shooter, BJ and I had actually chatted over social media before. We got to talking about the TMB and I knew I had to have one when the production models came out where I was happy to buy one myself. As luck would have it a deal was struck where I would get my own TMB in return for the loan of my Area 419 Sidewinder and Terminator TT brakes. As I was due to shoot a national level PRS match in Mildura, BJ offered to temporally send me one of his prototypes to test and use in the match. Obviously It would get his product some exposure as well. Once I received the TMB I set about coming up with a load to use with the TMB to test it.

Due to some time constraints I had mainly been shooting factory Hornady 6.5 Creedmoor 140gr American Gunner ammunition in my Accuracy International AX. I had started some load development using Hornady 130gr ELD-M projectles, ADI AR2209 (H4350 for our American friends), Lapua Small Rifle Primer brass and CCI 450 small rifle magnum primers. Up to this point I had run a pressure test and OCW test in order to find a flat spot in velocity I was comfortable with. I decided to settle on 43.0gr of the AR2209 giving me an average muzzle velocity of 2870fps over 10 shot strings. This was repeatable giving me SD’s of 5.3fps, 7.9fps and 5.9fps over three 10 shot groups. This was a load I was extremely happy with which I achieved without too much work and it should give me decent barrel life.

This took me to the TMB itself. When compared to some other brakes on market it looks like a rather large unit; and you know what? It is. But then you look at adding a tuner to your current brake and it is quite comparable. The  TMB comes in three pieces. it has the brake portion, a locking collar and the tuner part with two grub screws. I won’t go into the details of installing the TMB as BJ has already done a fine video on this, but let me assure you it is quite simple and you shouldn’t have too much difficulty with the installation process.

Following the instructions detailed in BJ’s video I set about firing groups at the various settings moving in 2 click increments on the tuner collar. You can see some of these groups below. What I found quite interesting is I could watch the groups on the paper be extremely repeatable with their shot pattern.

After firing groups at settings 0, 2, 4, 6, 8, 10, 12, 14 and 16 I decided go back and test setting 2 and setting 10 again. Where I eventually settled on setting 10 giving me a 5 shot group measuring 0.205 MOA measured using the Ballistic-X app on my phone. This was achieved on my very next group on this setting. Since then I have achieved similar results with a 5 shot group no bigger than 0.304 MOA. This load and the TMB together in my rifle produce excellent results. I have also seen similar results from BJ himself using various of his own rifles.

Setting 10 produced this 0.205 MOA group on the next try. This was repeatable with multiple groups.

So what is the “so what” of all of this? I am a convert. The TMB is going to save me quite a bit of time in load development time and components. For the factory ammunition shooter it will allow you to get the most out of that ammunition in your rifle. It really does tune you barrel harmonics with the load you have chosen. With careful preparation and good shooting fundamentals you will be able to achieve similar results. I am that pleased with the TMB I have ordered myself a second one for another barrel and I am also in talks the BJ for a .338 version for my Lapua Magnum. For a full-time working parent and competition shooter and hunter I am a firm believer in the ability of the TMB to save me time, help me achieve the smallest groups possible with my ammo and rifle and as a bonus I think it looks cool too.

If you want your own you can go to BJ’s site www.strikewithoutwarning.com . They currently retail for USD$325 and ship from Texas for North American customers and from Melbourne, Australia for the rest of the world. They are designed right here in Australia; however, they are made in the USA as that is his biggest market.