A2 Birdcage for 6mmx45 Build?

[HairyDemon]

There are not very man choices for Barrels when it comes to 6mmx45 so I am going to go with BlackHoleWeaponry.com for my barrel. Now I have a choice of a Target crown or a 1/2-28 threading like an AR. I don't really care about the thread but I am planning in future to get a 308 suppressor that I would be able to use on the the 6mm and .223 if I do my HW and make sure I can get an adapter that will work that is why I am tempted to get it threaded. All of that said I looked down barrel of one of my AR's that wears a standard A2 Flash hider and it looks like the opening is quite large and I would guess has a good 1/8th of an inch on all sides around barrel. So what are your opinions about running an A2 birdcage on a 6mmx45?

 

[ORD]

A basic birdcage FH will work just fine and cause you no fitment issues running the larger 6mm (vs. 5.56) rounds, but, as with all of them, they really are not all that effective at reducing flash all that much.

That said, nearly ALL of the QD style suppressor mounts that I am aware of are available in 1/2x28 thread patterns and most could be opened up slightly to accommodate the 6mm round. Just by way of example...AAC actually makes their 51T suppressor mounts in 7.62 (which will work with sub calibers in 6.8 and 6.5...with 6mm too obviously) in 1/2x28 with no modification to the muzzle devices required (like opening up a 5.56 model to ensure a 6mm projectile will clear it and cause no issues with your can).

The only word of caution with respect to factory production threaded barrels, including those from BHW, is that you'll need to ensure that the threads are actually cut concentric to the bore. Having them be off enough to cause damage to your muzzle device...not to mention your can...is a bigger problem with SOME barrels/mfgs than you might think! Not sure on BHW, but I recall seeing reports in the past relating to that issue. Depending on what can you are buying, warranty issues with the barrels you use with the can, etc., it may be preferable to get a plain-muzzle barrel and get it threaded by a reputable smith who can ensure the proper threading job is done within specs of your suppressor mfg in terms of concentricity.