Yup when you were lined up next to other shooters you had to time shots between the neighbor’s shots.
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JP Tank Brake (Recoil Eliminator) for PRS Tactical .308
- Thread starter MidRangeCrisis
- Start date
Yup when you were lined up next to other shooters you had to time shots between the neighbor’s shots.
The lineup will be:
Bare muzzle
Gemtech HVT
JP Recoil Eliminator
JP Standard Compensator
"Mike" Brake (Buddy made it. Sort of a Hawkins Tank brake with a single top port)
MBM 4 port Beast
APA Fat Bastard Gen 3
419 Sidewinder
PVA Jet Blast
Load will be 175 grain Barnes Match Burners at 2650+/- FPS pushed by IMR-4166 because it's a bullet and powder I have a lot of. I will verify velocity with a Magnetospeed V3.
Rifle is a Tikka T3 LA in a composite stock with a 24" 1:10" Proof CF Sendero profile barrel. Magazines are modified for the SA cartridge loaded long.
Shooting should be off a bipod prone or benched in 40-50 degree weather in Middle TN at the Montgomery County Shooting Complex in mid January. I'll try to replicate the target deviation test performed by PRB aaaaall the way back in 2015 and see what happens.
Bare muzzle
Gemtech HVT
JP Recoil Eliminator
JP Standard Compensator
"Mike" Brake (Buddy made it. Sort of a Hawkins Tank brake with a single top port)
MBM 4 port Beast
APA Fat Bastard Gen 3
419 Sidewinder
PVA Jet Blast
Load will be 175 grain Barnes Match Burners at 2650+/- FPS pushed by IMR-4166 because it's a bullet and powder I have a lot of. I will verify velocity with a Magnetospeed V3.
Rifle is a Tikka T3 LA in a composite stock with a 24" 1:10" Proof CF Sendero profile barrel. Magazines are modified for the SA cartridge loaded long.
Shooting should be off a bipod prone or benched in 40-50 degree weather in Middle TN at the Montgomery County Shooting Complex in mid January. I'll try to replicate the target deviation test performed by PRB aaaaall the way back in 2015 and see what happens.
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i'd recommend a phoneskope in slo-mo
would be interesting to see not only the reticle moving but also speed/length of the recoil too
would be interesting to see not only the reticle moving but also speed/length of the recoil too
I figured on using a time synched 240 FPS camera on target with colimated laser, a very fast perpendicular camera at the shooting position, and a slo-mo phoneskope as you suggest.
I want to try port tuning the FB brake besides and seeing which ports are firing and dialing it in to track the target will be key in an evaluation. Hell I payed for the feature, might as well right?
sounds like you have a good gameplan. look forward to seeing your data
I have a JP tank brake on my 308. It works fine, I got it timed by my gunsmith which is convenient. I didn't snag it on anything in the few years I used it.
It's not any better or worse than others I've tried. These days it's best to get a self timing brake. I've got a Hellfire brake that works well, but does direct some blast back to the shooter. That's normal for the most effective brakes I've seen though.
I do want to try the Hawkins Precision Tank self timing brake. Once it's set up taking it on and off is the same as having a brake timed by a gunsmith. It's annoying taking the Hellfire on and off.
It's not any better or worse than others I've tried. These days it's best to get a self timing brake. I've got a Hellfire brake that works well, but does direct some blast back to the shooter. That's normal for the most effective brakes I've seen though.
I do want to try the Hawkins Precision Tank self timing brake. Once it's set up taking it on and off is the same as having a brake timed by a gunsmith. It's annoying taking the Hellfire on and off.
Lots of negativity on here. The brake is extremely effective, but maybe not for all scenarios. I have one. I love it, but it's recently been replaced by a Killer Invocations Killer B. Can we sell stuff on here? If so, and your still interested, I'll sell mine cheap with a JP double sided lock washer and jam nut. The brake is cool, just not what I need and I don't need $$ sitting on sitting in my parts kit.
It's. 30cal with .875 OD
It's. 30cal with .875 OD
PM me separately to avert the perception of a sale post in the wrong forum. I've hot one ordered from JP but I suspect I'll have use for another soon.
Stay tuned for results from the test too. I'm not promising anything but I have a hunch...
SJC Titan is the king of 5.56 brakes. also fantastic on .300 BO supersonic. The Titan beat out the Precision Armament M4-72, which had won the previous two test runs.
www.thetruthaboutguns.com
for .308 brakes, the Precision Armament’s M4-72 Severe-Duty Compensator won, but the SJC Titan was not tested. I have no doubt that the Titan would be right there in the running like it is in the 5.56 tests.
For those who say that they're all the same...science doesn't lie.
www.thetruthaboutguns.com
AR-15 Muzzle Brake Shootout #3 - The Truth About Guns
Welcome to the third installment of our 5.56 muzzle brake testing series. This time around we’ve put 42 new muzzle devices to the test, measuring the recoil reduction performance of each. Recoil Testing The procedure for this test was the same as the previous brake tests. You can find the first...
www.thetruthaboutguns.com
for .308 brakes, the Precision Armament’s M4-72 Severe-Duty Compensator won, but the SJC Titan was not tested. I have no doubt that the Titan would be right there in the running like it is in the 5.56 tests.
For those who say that they're all the same...science doesn't lie.
.30 Caliber Muzzle Brake Shootout - The Truth About Guns
◀Previous Post Next Post▶ In response to popular demand, we’ve scaled it up a notch and have taken the 5.56 muzzle brake testing to 7.62. Specifically, 24 muzzle devices threaded 5/8-24 for use with .30 caliber cartridges joined in the fun, all of them getting tested for recoil reduction...
www.thetruthaboutguns.com
I've been shooting these breaks since 2009. The Tank break works well on .308, 6.5 CR, 6 CR, 6 BRA, and .223 rem. I've been shooting Tac matches since 2012 and at no point ever did I "catch it on a barricade". Honestly, WTF are you all doing with your muzzles that that would be an option? If you are putting it in a hole too small for the barrel that it would become caught then you likely wouldn't be able to look through the scope to see your target.
Also, it's loud... like all of the rest of the breaks that work. It is a consequence of redirecting gas.
Also, it's loud... like all of the rest of the breaks that work. It is a consequence of redirecting gas.
i can already tell you the results of your test without you ever firing a round but ill be curious to hear what you come up with.
any brake with angled ports is going to reduce recoil noticeably more than a straight port design and is why just about everyone making brakes has gone to that design.
ive been doing this testing and will finish with the brakes im testing this weekend....i just got the harrels this monday(they are straight ports)and my smith got them opened up tuesday night....i dont have a fancy sled or cameras i lay down shoot 5-10 rounds to get a good feel then get up swap the brake right there and shoot another 5-10 rounds.
as i said in post #27 i shot the 419 and the hawkins brakes side by side last weekend(i also shot the JP tank and the 419 side by side years ago when i switched to the 419)and the 419 has noticeably less recoil than the hawkins and JP but the 419 also had noticeably more muzzle blast so thats going to be the trade off here...if you dont mind the muzzle blast then the angled port brakes are the best at recoil reduction.
I'm sure you're right as the common sense physics of it all makes sense. I was particularly interested repeating the test methodology aimed at determining which brake helped most to keep the target in the scope during the shot. Thus all the newfangled camera stuff.
The 2015 test showed that a lot of brakes with perceived and measured recoil reduction weren't necessarily tracking very well, though better than bare muzzle or suppressed for sure. Since my test rig is a lightweight in the first place, both attributes should be amplified considerably and I'll be happy to find the brake that empirically performs its task best in my case.
gotcha...i can tell you this...the hawkins stays on target slightly better than the 419...i have 2 419s and both want to go left the hawkins moves straight back...and dont get me wrong its not like the 419 jumps WAY left it does stay on target even with a light hold but ALWAYS ends up on the left side regardless of the hold on the rifle.
Done. I found the recoil reduction form the JP impressive. It's odd. Takes all the snappyness (not sure that's a word) out of my little. 270 Win and turned the recoil into a soft push. I did find, that if I'm not careful, that muzzle flip is still a thing when I get lazy with my positioning.
so yesterday i went out and shot all the brakes ive been playing with side by side...in hide site i wish ida taken some pictures....50 rounds total...id shoot 5 then swap to another brake then shoot 5...after shooting these like this ive found that no matter the grip on the gun they all want to go left...not uncontrollably so but none the less left...i know i said the hawkins was straight but it to moves left.
heres my thoughts for what their worth...keep in mind im looking for the most effect brake with the least amount of muzzle blast directed towards me....
area 419...of the brakes i shot yesterday this is hands down the best at reducing felt recoil but the worst for muzzle blast towards the shooter also with a light hold jumps left more than the others
hawkins precision...this one stays on target just a tiny bit better even with a light hold and zero back blast but does not reduce recoil as well as any of the others i shot...the difference is slight and probably only noticeable if shooting side by side like i did
harrels 4 port...this is a very nice brake...only slightly more left jump than the hawkins but reduces recoil better and zero back blast...down side you have to have your smith bore the hole out to the appropriate size for the caliber your shooting...im not sure if harrels will open the hole up might be worth a call.
harrels 3 post tactical...this is the new love of my life here LOL!!...this brake is awesome as it does the best at what i want my brake to do.
noticeably less rocoil but slightly more left jump than the hawkins...slightly less recoil and slightly less left jump than the harrels 4 port and by slightly here i mean i really had to pay attention with the 2 harrels...i shot 5 swapped to the 4 port shot 5 then swapped back to the 3 port then back to the 4 port then back to the 3 port.
down side again you have to have your smith bore the hole out to the appropriate size for the caliber your shooting as with all or most harrels brakes but at $45 bucks IMHO these are a steel!
heres my thoughts for what their worth...keep in mind im looking for the most effect brake with the least amount of muzzle blast directed towards me....
area 419...of the brakes i shot yesterday this is hands down the best at reducing felt recoil but the worst for muzzle blast towards the shooter also with a light hold jumps left more than the others
hawkins precision...this one stays on target just a tiny bit better even with a light hold and zero back blast but does not reduce recoil as well as any of the others i shot...the difference is slight and probably only noticeable if shooting side by side like i did
harrels 4 port...this is a very nice brake...only slightly more left jump than the hawkins but reduces recoil better and zero back blast...down side you have to have your smith bore the hole out to the appropriate size for the caliber your shooting...im not sure if harrels will open the hole up might be worth a call.
harrels 3 post tactical...this is the new love of my life here LOL!!...this brake is awesome as it does the best at what i want my brake to do.
noticeably less rocoil but slightly more left jump than the hawkins...slightly less recoil and slightly less left jump than the harrels 4 port and by slightly here i mean i really had to pay attention with the 2 harrels...i shot 5 swapped to the 4 port shot 5 then swapped back to the 3 port then back to the 4 port then back to the 3 port.
down side again you have to have your smith bore the hole out to the appropriate size for the caliber your shooting as with all or most harrels brakes but at $45 bucks IMHO these are a steel!
So the three port beat the four port Harrels in your evaluation? Interesting. Is the port configuration the same? I've heard of such and it has the math behind it once you get used to the idea that the projectile acts as a plug of sorts if only momentarily.
Still waiting on all these brakes I ordered to run my evaluation. What caliber dud you use? 6.5CM right?
the 3 port does not have the open chamber in the first port its basically just a hole if that makes sense...i can pull it and take pic if you want.
6BRA 109 hybrids at 2875ish.
No I get it. That's even more interesting though. Be neat to see what's going on there on camera with each configuration
@MidRangeCrisis sorry for jackin your thread i just figured since you were aleady looking at brakes.....
@Stoweit
the 3 port top 4 port bottom...note the small hole in the 3 port at the first(closest to right)port then note on the 4 port you can see the threads that screw on to the muzzle.
looking at the first chamber on the 4 port notice its the same size as the muzzle threads 5/8"
looking at the first chamber on the 3 port notice the first chamber is tapered and has a small exit hole.
im going to play with these a bit more today and make sure which one i feels best.
@Stoweit
the 3 port top 4 port bottom...note the small hole in the 3 port at the first(closest to right)port then note on the 4 port you can see the threads that screw on to the muzzle.
looking at the first chamber on the 4 port notice its the same size as the muzzle threads 5/8"
looking at the first chamber on the 3 port notice the first chamber is tapered and has a small exit hole.
im going to play with these a bit more today and make sure which one i feels best.
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so im going to have to back track and eat a little crow....after shooting 40 rounds through the 3 port yesterday i went out this morning and shot 5 rounds with no brake then put the 3 port on and shot 5 then put the 4 port on and shot 50 rounds through it.
i think the recoil is the same just a little different or maybe slightly better with the 3 port but after shooting 25-30 through the 3 port yesterday and 50 through the 4 port today i like the 4 port a little better...i like the look of the 3 port better but the 4 port just seems a tiny bit better after shooting a larger sample with it.
i think the recoil is the same just a little different or maybe slightly better with the 3 port but after shooting 25-30 through the 3 port yesterday and 50 through the 4 port today i like the 4 port a little better...i like the look of the 3 port better but the 4 port just seems a tiny bit better after shooting a larger sample with it.
Me too. This should be a good little experiment. I'll see if I can write it up with findings and graphics to support but for the most part I'll just post it here.
I've got the green laser module, phoneskope, and offset rail mount on order. I'll see about a video time-synch app for the phones involved here shortly. Might just have to use the spotting scope and another phoneskope or something if I cannot put a camera at the target.
I'm thinking I will apply a FOV deviation ring overlay to the results. It will be calculated of course but I'd appreciate input on what most of you are using for FOV size relative to distance. Most targets are 1 to 2 MOA in PRS right? Maybe a .25" or .50" dot on 1" grids at 25 yards will work. I'll just interpolate the results at various distances based on the measured angular deviation in close.
So, what magnification and FOV are you guys running at 100, 300, 500, and 1000 yards?
I've got the green laser module, phoneskope, and offset rail mount on order. I'll see about a video time-synch app for the phones involved here shortly. Might just have to use the spotting scope and another phoneskope or something if I cannot put a camera at the target.
I'm thinking I will apply a FOV deviation ring overlay to the results. It will be calculated of course but I'd appreciate input on what most of you are using for FOV size relative to distance. Most targets are 1 to 2 MOA in PRS right? Maybe a .25" or .50" dot on 1" grids at 25 yards will work. I'll just interpolate the results at various distances based on the measured angular deviation in close.
So, what magnification and FOV are you guys running at 100, 300, 500, and 1000 yards?
I think most of us are somewhere between 15-20 all the time. Though I've heard of some other shooters staying almost maxed out in magnification.
i run 18-23 during practice and matches and 28-30 during load development...depending on mirage.
Some people don't like data because it contradicts their opinions.
Contrarily, shooting success relies a great deal on shooter confidence and the perception that what they are foing/using is "right" so it follows that there should be a little territoriality to opinions.
I am by no means a new shooter but PRS is a new game for me so I am novice in that respect. I enter with full appreciation of my shortcomings as a shooter and look forward to improving them relative to the nuances of this game. One thing I have learned though us that "solving" or preempting unknown problems with a new gun or gear is a pastime invented by gun makers and match sponsors.
This test will be done primarily to satisfy my need to adjust my rig in one very specific way as well as I can in order to address one critical aspect of the game for new shooters who have not yet become transcendent in their faith in their gear: staying on target in the scope in a lightweight rig that I have on hand. I'll try and learn the game better over time as a shooter so that if I ever drop the coin on a purpose built PRS rig, I'll have skills and habits that make the most of its peculiarities.
I may add a test event to replicate more closely the behavior of lighter bullets shot from heavier guns at gas volumes approximating their respective cartridges. I could add weight to the gun and dial down the load to more closely represent 6 Dasher, 6 CM, 6.5 CM or nearly any other reasonable cartridge. At least this way some folks besides the oddballs like me can infer some relevance on this muzzle brake test.
Anyone want to see that?
Looks like 15-25× FOV calculation would serve the most shooters. Since I run a fixed 10X on some guns, 16x on others, and a new (to me) 5-20x50mm SWFA SS HD FFP scope just came my way I will do the math on shots for 10x, 15x, and 20x FOV. I can barely read the reticle below 10x on this scope anyway do I doubt I would use anything less in a match.
I'm interested in how you plan to quantify that result. Unless I misunderstand what you're trying to do, creating a measurable way to express how well you can "stay on target in the scope" as you change system inputs is the key to the whole thing.
I wouldn't mind seeing every brake tested using the same load/velocity/brake muzzle size.
What are you going to do to make sure the ports on the brakes are level?
Can't he record each shot and watch where the rifle pointed when it was the farthest off target? Its good data if the brake makes the rifle consistently recoil in one direction and distance from the center of the target.
Basically I am going to repeat this test for the brakes I have on hand with my gun and match load.
Muzzle Brakes: Ability To Stay On Target
One important aspect of a muzzle brake is helping the rifle stay on target. In fact, I was discussin...
precisionrifleblog.com
Grid Target at 25 yards, collimated laser dot on sight center, time synched slow-motion cameras on the target to track deviation from the dot throughout the shot with side view camera and scope camera to provide correlating feedback. I'm putting the laser module between the scope and barrel and offset slightly from the left. At the distance it should not skew the deviation much but I realize it's not perfect.
My rifle is a lightweight (proof cf barrel--about 10 lbs) Tikka T3 tactical .308 shooting 175 grain bullets at 2650 fps with 95.7% of the powder burning out in the barrel and a muzzle port pressure of ~480 BAR as the bulet leaves the barrel (calculated by Quickload 3.9).
I will only use my rifle configuration at this point with my standard match load as a control. 175s at 2650 in my rig. The brakes will be the only thing that changes.
I could see loading up some recoil/gas generation surrogate loads and/or adding weight to represent lighter loads or heavier guns. I have bullets down to 110 grain and powders that can get them up to speeds like you see in 6 Dasher (etc) at similar gas volumes through the brake. Adding weight is easy enough. It would not be perfect but it could be useful to see brake performance related to more conventional PRS configurations.
I will check level on the ports both laterally and vertically after installation with a bubble level and the bipod/bag adjusted to get the crosshair and laser on the dot and the bore axis and ports oriented as close to perpendicular to the target as possible.
Just do 20x. Itll be easiest. Set to max and hit record. Hard to screw that up.
Trying to scale fov shit to compare against scopes is really really tough. Here is my attempt at using apparent field of view as my baseline but Im not certain it makes any sense. Suffice to say that we (I) really only care about how far off target the muzzle goes in a muzzle brake test relative to the other brakes, not what else you can see through various scopes which is an entirely different problem.
Min and Max Linear FOV are published
I converted some from meter@100m to feet@100 yards, most are published with feet and yards though. S&B 5-25 is 5.3 meters fov @ 100 meters at 5x. Thats 5.3*3.28=17.3885' at 100 meters, multiply it by .9144 to get it to yards and you end up with 15.9'@100yards. 25x is 1.5 meters, thats 4.9 feet@ 100 meters x .9144=4.48'@ 100 yards.
Angular FOV is derived from this article https://www.opticsden.com/what-is-field-of-view/ which claims that 1 angular degree is equal to 52.5'@1000 yards, a tenth of that gets you to 5.25'@100 yards.
Apparent FOV is magnification*real FOV
Apparent FOV @ 20x to get them all to the same baseline I took the a max magnification and divided it by 20 to scale all of it to the same level and then multiplied it against the apparent FOV at max magnification.
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Whew that's some data right there. Yeah I was more thinking of a rough range based on what I have on hand. My scopes are pretty plain-Jane compared to others but I figure being able to say at 'x' FOV/magnification I should stay on target at 'y' distance using 'this' brake. Sort of a way to see how much it really matters.
It will just be a math exercise and no additional shooting would be required.
Couple pictures of the brakes I have so far. More arrive today so I will update as able.
"Mike" Brake: angled three port bored to .338 with a single straight up vent on top. Should be a pretty good middle of the road solution.
JP Enterprises Standard Brake: two port design with wide aperture and a hybrid rear side half angled front port and two lateral vents drilled at opposing relative angles to produce what appears to be 90 degrees of separation between left and right. Vertex of the 90 seems to be at the radius of the forward end and ceiling of the brake in each window. I expect moderate recoil reduction and probably a good amount of semi tunable lateral stability based on venting on top.
"Mike" Brake: angled three port bored to .338 with a single straight up vent on top. Should be a pretty good middle of the road solution.
JP Enterprises Standard Brake: two port design with wide aperture and a hybrid rear side half angled front port and two lateral vents drilled at opposing relative angles to produce what appears to be 90 degrees of separation between left and right. Vertex of the 90 seems to be at the radius of the forward end and ceiling of the brake in each window. I expect moderate recoil reduction and probably a good amount of semi tunable lateral stability based on venting on top.
Its funny this thread has been so popular at this time. I have been working on some CFD analysis to optimize brake design.
if you what to make/design an optimal brake design one that reduces recoil as well as the angled port brakes but with straight ports.
Nerd.
But seriously I am impressed. There is more of this on the YouTube for already made designs and reference.
I think you'd appreciate these two papers done over the last several years on the subject. I don't have the tools to assess the JP Tank or other brakes on hand but I dig the math behind the madness.
Computer aided design and analysis of a tunable muzzle brake
This research work deals with the design of a tunable muzzle brake [10] for a rifle chambered in 5.56 × 45 NATO ammunition. It proposes to solve the p…
www.sciencedirect.com
Numerical Simulation and Experiment on Impulse Noise in a Small Caliber Rifle with Muzzle Brake
Blast waves generated from the muzzles of weapons may exert negative effects, such as shock waves and impulse noise. If the weapon is fired with a muzzle brake, these effects are recognized to be more severe. This paper discusses the influence of the muzzle brake on certain aeroacoustic noise...
That and the CFD solidworks model of the JP Tank I was referring to.
Just to add one last plug for the JP Recoil Eliminator (Tank Break). I like to think this video says it all.
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