I posted this is rifles uppers lowers barrels etc. But then i thought "wait a min, this would go better here!"

I am currently in possession of a Criterion Hybrid Barrel that has been straight jacketed by teludyne tech.

The product is a very interesting piece of kit. For those unfamiliar with the item:

The Straight Jacket system was applied over a criterion chrome lined hybrid profile barrel. The barrel is turned down to a pencil profile and then a sleeve and media was put between the sleeve and the barrel. This media is claimed to wick heat away from the thin steel barrel and extend barrel life by keeping the steel cooler. A typical test TT asks a shooter to do is to put their finger in the chamber. Indeed I was able to put my pinky finger in the chamber after a 40 round string.

Supposedly, it is 600% IIRC stiffer than a conventional barrel and offers around 7x the life of a conventional barrel IIRC.

I have a grouping which is interesting, but nothing conclusive at the moment. In short, I believe I am the weakest link in the barrels potential performance. Those flyers, If excluded, equate to a 7 round group of .62 MOA. As is necessary I included the data for the full 10 round group.

The load used is my reference load. 55 grain Hornady V Max with 25 grains of varget for 2900 fps and a sd of 9 fps.

The ridle currently sits with a fixed power 10x, but a 15x optic would have been nice for the testing, but I do not have such glass available at the moment. A machine rest would be ideal for additional testing.




The six round group above fits inside of a dime with room to spare. The whole ten round group with my outliers is still 1.1 moa.

The CEO literally said I could turn around and use this as a LMG type rifle, and then shoot it as a SPR without any change to the configuration. The barrel won't burn according to TT. Needless to say this will be the hardest thing to test as I don't have an unlimited supply of XM193 to test the claims of 7x the barrel life.  

Cal Zant noted some interesting heat characteristics in Litz' modern advancments vol 2 and under FLIR it did indeed remain the coolest barrel tested. Cold to warm bore drift was also minimal.

Just wanted to share some early info on the kit. I am going to obtain a thermocouple and probe to measure heat in the bore and external to the bore and we will compare to a modern barrel.

Im writing up a full review on it, but i want additional data before publishing.

It truly intrigues me. This barrel is chrome lined with match accuracy and super extended barrel life according to TT.

Every time I read of review of their products, it's glowing.

Curious...how much does that run?

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Picture of a three round group I shot with my straight jacket barreled AR10.  This thing will shoot!  I just reload with that recipie and shoot lights out!

In my experience, accurate barrel life directly correlates to erosion/torching of the throat.  How would wrapping anything around the outside of a barrel do anything to mitigate that issue?  I understand the heat dissipation idea, but it doesn't change the way the hot gasses and bullets act in the throat.

So in Modern Advancements vol 2 Cal Zant interviewd Alan of Teludyne

What he said in a nutshell is that the bore in the throat and foreward of the throat begins to work harden from the heat, pressure, and friction while the material around the bore begins to slowly heat up and cool down resulting in a softening of the metal surrounding the bore. As the barrel heats up it is basically floating a work hardneden surface on a softer metal.

According to TT this is where accuracy degredation comes from.

I have no way of testing this mind you, because if their claims of 7x barrel life are true i dont have enough ammo to test it.

However, are their any tests you would like to see with the barrel from a precision standpoint?

I have been testing the barrel for a few weeks and now need some ideas about what the precision community wants to see.

I have about 800 rounds of 77 grain reloads, 200 xm193, another 400 rounds of 55 grain ammo vmax reloads (my test bullet) and a 10x optic.

I am going to get with a freind to borrow a higher magnification optic to really see what this product can do.

Of note one of my loads with varget was 30fps faster than when i last chronod it. From 2650 avg 10 shot string up in PA at around 65 degrees to 2680 here in south texas after the barrel was jacketed in 90 degree weather.

Is that a typical velocity swing for Varget? Same load. 24 grains of varget on a 75 grain HPBT cci primer.

I have a bolt action with a tt straight jacket.  I found that for me it took three round groups from .75 to .25 and t rounds from an moa to a .5 moa.

Probably the biggest change is that it is extremely consistent with surplus/cheap ammo.  I've yet to find NATO surplus too
And or federal white box that wouldbt shoot into an moa now.

For the price I am not impressed

The actual test results don't seem worthy of the praise.
https://store.appliedballisticsllc.com/ProductDetails.asp?ProductCode=0008


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I agree the price of entry isnt for everyone. However, if the claims of 7x the barrel life are true, how would that affect your perceived value?

Also note on a cold bore it was, however slight, the most accurate barrel tested.

Weight is also less than a heavy palma, but not quite as light as the carbon barrels.

So that aside... If i were to make a video of this barrel, how many rounds down the bore would you like to see before I then shoot it for groups again? What would you guys consider "torture" on a semi auto precision barrel? Right now its grouping pretty well.

I have no dog in this fight as far as emotional investment. Barrel cost me nothing but shipping. I am reviewing the product and would like some ideas from the precision community for additional testing.  

Another company will be bore scoping the barrel at some point in the future. Criterion offered to evaluate it after testing. I am keeping a log of round count.

This should be fun.

If 7 times the life were true then it would be well worth the money but I would have to call BS on that claim. I have not seem such a claim of 7 times. I have seen that it can bring back some life to old barrels.

I have to make a correction:  i recently saw a thread where David Bailey noted 5x barrel life not 7x.

Heat kills barrels via throat erosion.

If you want to test it, you can do aimed fire for 500 rounds, 1 shot every 3-5 seconds.  Test for accuracy before and after.

To turn it up some, you could mag dump for 2k rds as fast as you can pull the trigger. Test for accuracy.

SJBS is claiming it is pressure damage and that is what their system is addressing.

As to throat erosion, does that really make the barrel lose accuracy or does it just make a particular load no longer accurate?

If I rework the load to be the same distance to the lands and bump up the powder charge to get velocity back can't I make it accurate again provided the rest of the bore and crown is fine?

I won't pretend to be a barrel genius or a metallurgist, but I'd always heard/been told that heat and friction caused throat erosion.

The rifling is missing from the eroded area.  It's just gone.  If it's "pressure" as the STBS folks claim, then their product should do an excellent job in preventing throat erosion.  

Throat erosion effects?  loss of accuracy.  I suppose you could reload to a longer OAL to get the projectile to the lands/grooves, but I don't know if it would work.

They are saying they are two different issues, I don't think they are claiming it slows throat erosion. They are claiming in the quote throat erosion isn't the problem on many of the used rifles they have done, they had pressure damage.

Something about the bore work hardening but the metal around the bore annealing causing an unstable barrel. The jacket is suppose to tame erratic whip.

Shot Semi Auto Today:



10 rounds of Hornady 53 ELD loaded to magazine length, 25 grains of Varget, and shot semi-auto from the mag. 100 yards.

Shot this ten rounder the other day.

My question is... What if the flyers are me? 8/10 rounds were one ragged hole.

I would like to see your groups with a 5.56mm match round pushing a 69 grain SMK or 77 grain SMK... My rifle in .308 is doing VERY well with FGMM, FGMM reloaded clones, and 165 grain SGK and SST with same powder charge.

Is this factory ammo, why are they crimped?

What if they are what it shoots? What if they are you?
Doesn't really matter, still good.

Since you are shooting 10 round groups,  I  wouldn't concern myself with those two shots.
It make zero sense to analyze a 10 shot group based on only 20% of the shots. More groups will tell you more.

If 80-90% of your shots are .6moa everytime well that gives you a better idea of want you can expect.

A better way to judge a group if groups is to use average to center, that kind of eliminates a bad pull or bad round.
If I shoot a 1 moa 99 shot group and the 100th round make it 3moa that doesn't mean the system is 3moa, it's still 1moa.

... .Of course for bragging on the internet you have to go by extreme spread.

Its vmax with cannelure. I ordered the wrong component. I reloaded it to magazine length and accuracy was nothing like above. When i loaded it to the crimp, and crimped it... Accuracy was as above. Big improvment suprisingly.

I will do the federal gold medal match for a reference load.

I have shot this barrel lots. I have one more test before i publish my data but it appears to be immune to heat related precision degredation. Round 41-50 was still sub-moa with another round of hornady ELD match. No cooldown between groups.

Accuracy wise i beleive i am getting some POI shift, but i need another range trip to eval that.

I understand you have to ship them your entire upper if you want the process done on an AR platform rifle.

I'm guessing the gas block is proprietary?  I know the gas tube they provide is straight.

I've become accustomed to adjustable gas blocks.  Do they offer an adjustable?

Box stock its an adjustible gas block via a setscrew on the side.

So the straight jacket application is left off of the gas journal on the barrel then?  You just need to send your gas block for them to install before the straight jacket is added?


Sorry, just trying to understand how this works.  The bolt action is simple, with a semi-auto...not so much.

No they give you a custom gas block that matches the 1.5 od of the barrel. Its permanent once its in place because its trapped by the composite jacket on both sides.

On my AR10 they provided a turnkey solution and sold me a complete upper receiver.

A buddy of mine is sectioning one.  He doesn't buy into it.

He's an engineer who works with exotic alloys on-call for medical device companies mainly.

Super cerebral guy, who also loves machining things, put himself through 2 different gunsmithing schools between cycle breaks in his engineering program.

It will be interesting to see his analysis of it.

They have to attach the gas blocks on AR barrels using a permanent solution as mentioned above.

I finished my first article on the SJ testing.

Teludyne Tech Straight Jacket part 1

So i also found out that Teludynes build is quite different from the Dracos barrel system.

The dracos barrel system is compatible with standard rail systems, standard barrel nuts, and the gas block os removable.

My Straight Jacket is married to the M4E1 system and while it can be seperated it is only usable with my Aero Build.

The dracos system is compatible with .308 DPMS and standard 5.56 upper receivers / rail systems.

Dracos also uses a "expansion chamber" to delay bolt unlocking in their AR 15 / 10 systems.

So while the dracos shares the SJ patent, it is not the same exact product.  

Any questions please feel free. I will follow up with part two later this year.

I shot with FGMM but that day was miserable and I struggled to group well. I am saving penies for a dedicated load workup optic around 24x.

Suggestions?

Don't know your budget.

I have had good luck with vortex scope.

Can you run a can on it?

I'm going with Proof Research.

The various rags that do articles on them have a shooter that knows how to shoot:

A)  under a quarter [0.250" @ 100yds] is the rule with industry match fodder  

B)  in the da-da-damn teens [<0.200" @ 100yds] with a particular industry load

Yeah, dagnabit to all hell, some articles are 3 shots per group BUTT!!! others go with the 5 rounds per group rule.

Yes you can but I dont have one at the moment.

Also good news.

This november I am arranging something with another blog so we can go full auto with this thing and then resume accuracy testing.

Very interesting read!   Nice wright up!

So, I take it this is same company that makes Dracos barrels, and am I correct in thinking Falkor Defense bought this company out or invested in it to make the barrels for the Falkor firearms and now are selling stand alone barrels to the public in the name of Dracos Barrels?

IMO, you have just backed up what Dracos test results claim on their website. I guess if they wasn't sure, they also wouldn't offer a lifetime warranty.

Dracos liscenses the straight jacket portion of the system and then refined the gas block with their own design.

Tagging this thread. I'm seriously considering DOJ dracos barrels.

I like the concept and the custom colors but what has my interest the most is the extended barrel life, I'm really itching for a 300 Norma mag build but barrel life is a concern. If the hype is true that may push me over the edge.

How much is a barrel? Maybe we can crowd fund this test. @jaqufrost  

Update.

I put 180 rounds down the pipe rapid fire. Got it on video.

Smoke and steam all over the jacket. Im not sure if that counts as precision barrel abuse, but that was all the ammo I was willing to dump at this time.

I wanted the brass. :D

Still maintains a 2 inch POI shift down when it gets hot just as before. Groups opened up a bit, but the barrel needs a good cleaning before I will call it one way or another.

To combat the shift down i bedded the barrel extension into the receiver with rockset and removed the heavy muzzle device that came equipped from the factory.

So now I am waiting on a good copper cleaner from brownells to give it a good cleaning and then I will retest for accuracy.

Was the Straight Jacket capped with the muzzle device when you removed it?

There is a seperate cap over the system seperate from the muzzle device.

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Just having some fun times with my 16” SJBS AR10 upper at the range.  Was having fun last Sunday stretching the range out to 600 yards with 168 grain FGMM and my reload clones.  Shot some IMI Razorcore 168 too with great results at 600.

This is a 3 shot grouping with 175 SMK over Varget that I am going to confirm at 100 and 200 yards today.  Used my Magnitospeed V3 and confirmed my muzzle velocity with my 168 SMK FGMM clones and I am getting 2460 FPS with single digit variation in 5round strings.

I’m having a lot of fun with this setup and want to shoot 800 yards ASAP!