Bullet Strikes Brake

[Hawk in WY]

I have read of suppressor strikes but never a brake.

Happened with my Dakota rifle in 7 mm Dakota. Load was on the warm side with Barnes 145 gr LRX.

Lilja Barrel. Not sure of twist but asking Dakota for the twist rate.

No damage to rifle, but part of the brake went down range.

Replacing brake but wish to avoid recurrence.

Only theory I can think of is an unstable bullet. The 145 LRX is particularly long for weight.

Only other observation is brass was slightly undersized and needed more than usual caming with the bolt.

Plan to properly size brass next time and use a TTSX bullet.

Other theories welcomed.

 

[PinesAndProjectiles]

My guess is the threads on the muzzle weren't concentric with the threads on the brake.

Was this the first shot fired after the brake was installed?

 

[Hawk in WY]

Around 300 rounds with same bullet fired through the brake before strike.

Rifle is back at Dakota. I will ask them to confirm concentricity.

 

[10ring1]

Maybe the bullet came apart coming out of the barrel? I'm sure any bullet maker has potential of making a defective one from time to time. Did u shoot any others of the same load?.

 

[Hawk in WY]

Bullet coming apart is a possibility, but Barnes bullets are all copper.

I shot the remaining ten from that lot without the brake with nothing unusual.

Carbon buildup in the brake seems unlikely but I suppose that’s possible.

Dakota’s brake design is pretty but same diameter as the barrel with multiple holes.

Not very effective.

 

[Rocketvapor]

Got a picture of the Broken Break?

 

[Milo 2.5]

Be nice to figure what caused it, my guess is the exit hole wasn't big enough and something clogged it. Suppressors extend out to 8", a brake barely over 2", it'd take a wildly errant bullet to wreck most brakes. All the baffle strikes I've seen or heard of, the can stayed on the gun or together.

 

[Hawk in WY]

Got a picture of the Broken Break?

I don’t. All that was left on the barrel were the threads and up to the first row of holes. Looked faintly like a bullet strike mark at 6 o’clock. The front end was launched downrange into two feet of snow. I will find it in the Spring.

 

[Hawk in WY]

Be nice to figure what caused it, my guess is the exit hole wasn't big enough and something clogged it. Suppressors extend out to 8", a brake barely over 2", it'd take a wildly errant bullet to wreck most brakes. All the baffle strikes I've seen or heard of, the can stayed on the gun or together.

That sounds right. I can’t imagine what might cause the brake to be clogged.

A squib would do it but I would have noticed that for sure.

I can’t believe carbon fouling would cause this since I clean through the barrel and brake with the same pass.

It sure would be nice to figure this out before I shoot it again.

 

[Milo 2.5]

I don’t. All that was left on the barrel were the threads and up to the first row of holes. Looked faintly like a bullet strike mark at 6 o’clock. The front end was launched downrange into two feet of snow. I will find it in the Spring.

Does the break mark have carbon built up like it was cracked for some time? At least it didn't ruin the thread job.

 

[Hawk in WY]

Does the break mark have carbon built up like it was cracked for some time? At least it didn't ruin the thread job.

Threads were undamaged.

Back end of the brake shows no cracks or carbon ring.

 

[Milo 2.5]

Threads were undamaged.

Back end of the brake shows no cracks or carbon ring.

Threads were undamaged.

Back end of the brake shows no cracks or carbon ring.

I meant where it sheared off, any buildup?

 

[Rocketvapor]

Might have just cracked then obstructed the bore.

 

[Hawk in WY]

I meant where it sheared off, any buildup?

Nope. By back end I meant what remained on the rifle.

It broke cleanly between the first row of holes.

That’s the weakest part of the design but there was still a fair bit of steel between the holes.

A glancing blow would not have sheared it off cleanly.

I would love to see the the front end but it’s somewhere under two feet of snow up to 100 yards away.

 

[Hawk in WY]

Might have just cracked then obstructed the bore.

That seems likely. Fairly certain there was a bullet strike at 6 o’clock which could have been the cause of the brake to fail, but I have no idea what might have caused the Bullet to strike the brake in the first place.

 

[Lucky Se7en]

How was the rifle shooting for the first 300 rounds and did you get any muzzle velocities?

 

[Hawk in WY]

Velocity just over 3,100 FPS from memory. I’m away from my log book.

Accuracy was around one moa out to 800 yards, maybe a bit better

Test target from factory was shot with TTSX 150 gr right around half moa

I could never get the LRX bullet to shoot that well.

 

[Rocketvapor]

I was commenting on the Brake cracking first, distorting, then obstructing.
Muzzle devices sometimes just crack.

 

[Sean the Nailer]

Shooting too fast, and you got 'heat sag'? Like they monitor and adjust for, on tanks?



I'm just glad that no-one was hurt here. Good luck on finding the answer. I am curious as to what the 'downrange' part looks like, but Spring is a fair-ways off yet.

 

[Deleted member 10043]

Never would have happened without a brake. Seen that right off. Try not to put somebody in ER and get sued. Negligence on somebody's part is my theory. Not necessarily you but you did pull the trigger.

 

[Hawk in WY]

I was commenting on the Brake cracking first, distorting, then obstructing.
Muzzle devices sometimes just crack.

This sounds like a reasonable explanation.

Design is pretty but looked a bit fragile from day one.

 

[Hawk in WY]

Shooting too fast, and you got 'heat sag'? Like they monitor and adjust for, on tanks?



I'm just glad that no-one was hurt here. Good luck on finding the answer. I am curious as to what the 'downrange' part looks like, but Spring is a fair-ways off yet.

This happened during very slow fire on a 20 degree day. Unlikely it got hot enough to sag.

The missing piece probably does hold the answer.

 

[Hawk in WY]

Never would have happened without a brake. Seen that right off. Try not to put somebody in ER and get sued. Negligence on somebody's part is my theory. Not necessarily you but you did pull the trigger.

Negligence? Really?

Shooting a rifle with a brake is not negligent

I may be missing the sarcasm.

I have heard of suppressor strikes but never a brake.

 

[MtnCreek]

I wouldn’t assume the threads are ok. They could be stretched out of spec.

 

[Hawk in WY]

Excellent point. The rifle is back at Dakota. I will have them run a thread cutting die over the threads.

 

[Deleted member 10043]

I didnt say shooting with a brake was negligent. I said shooting with a brake that a bullet struck was negligent on somebody. You would have found that out if somebody or yourself was injured. There would have been a lot of long talks and questions.

 

[Hawk in WY]

I didnt say shooting with a brake was negligent. I said shooting with a brake that a bullet struck was negligent on somebody. You would have found that out if somebody or yourself was injured. There would have been a lot of long talks and questions.

In many cases, yes.

In this case, the brake separated cleanly. There was no obstruction of the bore.

Sorry if I misunderstood your post.

 

[bax]

Too much speculation. The missing link is the piece of steel that is down-range. An inexpensive metal detector should find it pretty quickly. I lost keys in a snowbank, bought a cheap metal detector and found them in about a minute. You might ask around to see if you can find someone who has a good one. Maybe they will help.

 

[Lucky Se7en]

I was commenting on the Brake cracking first, distorting, then obstructing.
Muzzle devices sometimes just crack.

That’s what I was thinking too and was wondering if it could have just been slightly glancing off for the first however many times it was shot then one time the fatigue caused a brittle failure or a plastic deformation resulting in an obstruction in front of the desired trajectory. I’d think unexplained inconsistencies in velocity before the failure could point to this

 

[Hawk in WY]

That’s what I was thinking too and was wondering if it could have just been slightly glancing off for the first however many times it was shot then one time the fatigue caused a brittle failure or a plastic deformation resulting in an obstruction in front of the desired trajectory. I’d think unexplained inconsistencies in velocity before the failure could point to this

Sounds right to me.

I will ask Dakota to check alignment of the brake with the bore which was mentioned early on.

Thank you all for sharing your collective experience and knowledge.

Much appreciated and a huge relief to have a few things to have Dakota check.