AR15 barrels that are ported properly for unsuppressed use will be overgassed with a silencer nearly 100% of the time, in my experience.


I have the same can that I use on an 11.5, 16, and 20" hosts. All were initially setup for unsuppressed use initially, and when the can was added, the additional recoil, harder carrier thrust, and additional gas to the face were very apparent.


I have found on all three that there is a happy medium with and adjustable gas block that will allow the rifles to cycle properly both suppressed and unsuppressed. There is also a suppressed optimum where the rifle functions really smoothly suppressed, but may be undergassed without the suppressor.


I favor the click adjustable, two piece, JP adjustable gas block. They don't rely on an unreliable jam screw to keep your setting in place. If they ever seize up from carbon and infrequent cleaning, a couple of days of allowing kroil to soak into the mechanism will free them right up.

Many people refer to adjustable gas blocks as potential failure points but I have shot most of my rounds through rifles such equipped at 3 gun matches, and lately at Precision Rifle matches competing in the Gas Gun division, and I personally have never had nor witnessed an adjustable gas block failure.

I have never broken a bolt lug but I usually retire my bolts when the barrel is shot out, they go into a marked spare parts box for emergency use. I have sheared bolts on a gas key.

3k on a bolt is a little short but not entirely surprising with suppressed use and anything made by man can fail and some will slip out that fail sooner than others.

quote:

Originally posted by KSGM:
The minor machining errors or defects you mention: would they be visible to a person's eye? If they would be, I reckon it would take a QC element hand inspecting every piece, to find them. That's probably not something that's practical.

Potentially. And if you see a defect it might not be a real issue anyway. There is a really good chance that tool marks, machining defects, scratches, etc that touch the base of the bolt's lugs will be the location a crack forms. But there still has to be conditions present to exceed the strength of bolt or fatigue the bolt until failure.

QC steps to find small issues would be time/cost prohibitive, you'd need someone with a good eye or a magnifier, and steps like dye penetrant testing to find machining errors that are too small to pick up by eye. And again, a minor defect might not even present as an actual issue depending on a whole lot of factors.

This is why inspecting the bolt is a very good idea to do during maintenance, but until you've have failures and seen bad parts in hand it's not always easy to identify what you should be looking for.

I definitely need to better-scrutinize critical components during maintenance. In the past, my efforts during a maintenance session have been more cleaning-focused, than inspection. My BRT tube is probably due for a check too.

quote:

Originally posted by KSGM:
I definitely need to better-scrutinize critical components during maintenance. In the past, my efforts during a maintenance session have been more cleaning-focused, than inspection. My BRT tube is probably due for a check too.

I think you are over thinking it. There’s a fine line between due diligence and paranoia.

Agreed. It's all subjective too. IMO, I likely haven't been doing my due diligence. I don't consider myself paranoid.