Tapered Shoulder Barrels

[Clint]

No doubt many have seen or heard of the Sig/Q style barrels with the tapered shoulder instead of the traditional square shoulder.

https://dqzrr9k4bjpzk.cloudfront.net/images/812059/812250528.jpg
L to R 1/2-28, 5/8-24, 5/8-24 Taper

This design has numerous technical benefits when used with a compatible muzzle device.

These benefits include better alignment/concentricity, stronger connection with a larger bearing surface and a self locking design that doesn't shoot loose.

This is especially important for suppressor mount applications and prevents loss of accuracy from mis-alignment.

The biggest drawback is the relative lack of choices for compatible muzzle devices.

However with the addition of a simple adapter ring that converts the shoulder back to square, any legacy muzzle device can be used.

Clocking or indexing is generally not possible, so muzzle devices are either a symmetrical design or accomplish clocking with a different set of threads.

We are considering incorporating this feature into our OPTIMUM barrels and offering a taper mount version of our Covert Comp 7.62.

All that said,
I'm looking for feedback on whether this feature a compelling reason to buy a barrel or a reason to avoid it?

[HammeredSole]

I think you already identified the biggest issue, which is limited selection of muzzle devices that are compatible. I have an MPX with the 13.5x1mm taper shoulder barrel. I am using a Griffin Armament 3 lug adapter, and that works fine. I am unaware of the particulars of shoulder alignment on this part, but it appears to be manufactured well and bore alignment is good with my suppressors. However, running a pistol caliber I am slightly less concerned with bore concentricity than I am on a rifle. I think I would be hesitant to get a taper shoulder rifle barrel if I know I will need to use an adapter to mount my muzzle device (I happen to use rugged MD's for their silencers). The way I see it, I can be certain of repeatable concentricity when I'm only using a barrel/shim/muzzle device arrangement. Adding in extra layers to the muzzle would be less than ideal IMHO, if only for my perception of potential issues. However, if you offered compatible muzzle devices which interface with popular silencer mount standards (Keymo, ASR, etc), you might have a winner. I can appreciate advancement of the state of the art and product improvements, but only find them useful when they are not really niche, or require additional parts to make them cross compatible.

This kind of reminds me of the KAC e3 system, and the SR15 mod2 gas system. While there is no doubt of it's superior engineering and function, a proprietary design and single source of replacement parts really limits what you can integrate into the total system. For me, I ditched my SR15 upper in favor of standard barrel extensions, gas tubes, buffer compatibility, and use the LMT E-bolt (which I consider to be just as good, if not better than the E3). While I know there "has never been a documented E3 bolt failure", I have piece of mind that I can swap, replace, and procure parts at a moments notice. Which incidentally, is more important to me than the theoretical superiority of a particular part.

[cynical]

Definitely, the limited availability of muzzle devices is going to kill this if it can't be overcome. An adapter eliminates any advantages of the design while introducing an additional layer of tolerance stacking that could potentially cause problems. If someone has to use an adapter (at further additional cost) to turn this into a conventionally designed barrel, why not just use a conventional barrel to begin with?

That said, I really like the idea and hope that MDs become available. Hopefully there aren't any licensing fees associated with producing compatible devices.

[Clint]

The taper spec has been open sourced, so muzzle device manufacturers are free make compatible versions.

[NongShim]

I’m overflowing with barrels right now, so this is not a commitment to order...

I think this is a move in the right direction though. All good QD mounts use a taper to index the can, putting it on the barrel too just makes sense. Proof is already doing the “Q” taper. I think the taper on my MCX is awesome. My next centerfire can will likely be a Trash Panda. After getting that, I’ll eventually have a Proof bolt gun barrel with that taper.

Seriously, if I didn’t have too many ARs at this point, I’d jump all over these barrels if you made them. I can’t justify rebarreling each and every one, but I’m sure I’d build a new 556 gun just to have one. I think the concept has tremendous merit.

[cynical]

The taper spec has been open sourced, so muzzle device manufacturers are free make compatible versions.

Awesome. I think closed specs are the quickest way to kill a great idea. And then look at what Magpul did with MLOK. Open spec, no licensing, now it's everywhere. I really like the taper idea, so I'm hoping it catches on.

[Bob Sacamano]

I would look at this as a negative. Even the 5/8-24 threads are a bit of a hang up for me because SF only offers their CT mounts in 1/2x28 and have not found anyone willing to open one up to 5/8-24. How about a run of optimium SPR barrels in 1/2-28 with a standard square shoulder? IMO, no option to time a muzzle device is also a negative. Will never run an open bottom MD if it can be avoided. Not an issue with the Covert Comp but it would be with many others.

Plenty of options already exist for taper mount adapters, they just go the other way (taper is on on adapter/not barrel).

Curious if I am just unaware of the issues people are having with a standard shoulder. In my mind, if it aint broke, dont fix it. I get that it is an an improvement (just like the 5/8-24 threads) but not practical yet. May raise more problems than it solves at the current time.

[MQ105]

Clint, due to the inability to time a MD, I'm not sure about the utility of this. I don't suppose cone-shaped shims are practical...?
How about a tapered/cone-shaped threaded part, similar to a thread protector, that could be used as a jam nut to time a MD? Wrench flats, of course. I like the 5/8x24 threads. We would need to get manufacturers to make MDs in that thread for 5.56, and with the taper.
I don't know if that would be any more stable/secure/aligned than the current shoulder arrangement. What do you think?

Edit: I missed this the first time: "adapter ring that converts the shoulder back to square, any legacy muzzle device can be used." That would solve the issue of using a standard/current MD.
I think the taper would be excellent for a direct-thread can with a matching taper.

[Jwknutson17]

I think these barrels are a huge plus when direct threading a suppressor on it. Or using a muzzle device that does not need to be timed. Having said that, I am not a huge fan of having to use a taper adaptor and then shims to time my muzzle devices and then add a Suppressor on top of that. And this is exactly what I am doing though for my 2 barrels on the Q the fix rifle I just picked up. Just too many things going on. But for the FH and direct thread suppressors, I see this as a huge plus.

[SomeOtherGuy]

The availability of muzzle devices is going to be a huge, if not THE, determining factor for whether this is successful. If you decide to make these I would suggest not only making a compatible Covert Comp, but also a compatible and inexpensive flash suppressor, like an A1 or modified A1 style, or an open prong type (short STG-58 style, or whatever you want to call it).

I see you're already offering 5/8x24 threads on a 5.56 SPR barrel, which I think is another significant improvement. For non-suppressor users it's probably more valuable than the taper.

If this were on the market with a reasonably priced muzzle device I want, I would consider this a selling point over an otherwise similar barrel. I would probably be willing to pay a small premium for the package of taper barrel + device over an otherwise identical barrel with 1/2x28 threads + comparable device, but I don't know exactly how much that premium would be.

[Biggy]

The availability of muzzle devices is going to be a huge, if not THE, determining factor for whether this is successful. If you decide to make these I would suggest not only making a compatible Covert Comp, but also a compatible and inexpensive flash suppressor, like an A1 or modified A1 style, or an open prong type (short STG-58 style, or whatever you want to call it).

I see you're already offering 5/8x24 threads on a 5.56 SPR barrel, which I think is another significant improvement. For non-suppressor users it's probably more valuable than the taper.

If this were on the market with a reasonably priced muzzle device I want, I would consider this a selling point over an otherwise similar barrel. I would probably be willing to pay a small premium for the package of taper barrel + device over an otherwise identical barrel with 1/2x28 threads + comparable device, but I don't know exactly how much that premium would be.

My thoughts exactly.

[Clint]

Great feedback.

This seems to be a love it or hate it feature at this point.

Probably the best way to slice it is to offer two different versions.