Which gas block for suppressor

[PNWTargets]

[montana]

The dwell time is when the bullet passes the gas port charging the system until the bullet exit the barrel..Using a suppressor increases dwell time.. The buffer or spring weight has nothing to do with holding gas pressure..

[PNWTargets]

The dwell time is when the bullet passes the gas port charging the system until the bullet exit the barrel..Using a suppressor increases dwell time.. The buffer or spring weight has nothing to do with holding gas pressure..

BCG dwell is when the BCG moves from static (back/forward). Spring pressure does affect this dynamic movement. When the BCG is still static as gas flows to it, that has to do with holding gas pressure. Possibly I am not explaining what I mean clearly.

[montana]

BCG dwell is when the BCG moves from static (back/forward). Spring pressure does affect this dynamic movement. When the BCG is still static as gas flows to it, that has to do with holding gas pressure. Possibly I am not explaining what I mean clearly.

The dwell time is the length of time the gas system is charged, period.

Bolt cam tract length (lock time).
Pressure curve (powder or bullet type)
Barrel port size (amount of pressure)
Bolt carrier resistance (force needed to move the carrier and bolt to cycle)

Timing of these variables are critical to function..Make changes to any of these variables and malfunctions can occur..

Moving the location of the barrel gas port will change the dwell time ( the amount of time the gas system is pressurized).
Change the spring-buffer-carrier weight, will change the cycle resistance to gas pressure..
Change the bolt cam tract and lock time changes..
Change the powder or bullet type and the pressure curve changes..
Open or shrink the gas port and the amount of pressure changes..
This is why they discovered the new buffer's added weight on the dwell time or bolt opening cycle was (negligible)..What it did do was slow the cycle rate (bolt carrier velocity) and prevented bolt bounce..
This is why locating the gas port farther from the muzzle will result in a longer dwell time and a gas port near the muzzle will have a shorter dwell time.
Adjustments are made all the time to the AR function with the gas system by opening or shrinking gas ports, gas port locations, buffer springs, weights and carriers and even different bolt cam tact time length..

When the bullet passes the gas port the system is charged, even in the bolt carrier. The Stoner internal piston will actually push the bolt forward while the system is charged away from the locking lugs in the barrel extension, relieving stress on the bolt, while simultaneously pushing the carrier the opposite direction . The bolt will not unlock or the carrier cycle until the port pressure has dropped after the bullet has left the barrel..The residual pressure in the system cycles the bolt carrier..The heavier the buffer, the slower the bolt carrier cycle (velocity) occurs. The lighter the buffer, the faster the carrier cycles (velocity) occurs..The dwell time is the time the system is charged..

A good example of dwell time is an air hose. If you have one length of hose and charge it with 120 lbs of air the system is charged with 120lbs. Disconnect the hose and the residual air escapes. Now hook up 3 lengths of the same hose and do the same. It will take a longer time to expel the residual air, even though it also has the same 120lbs of air. That is dwell time..

[montana]

Here is a description from the Aberdeen Proving Ground ballistic research laboratories:

The pressure variation with time at determined by the gas flow in the barrel.The mass flow through the port is small compared to the mass flow in the barrel itself,and the effect of mass removal is negligible on the pressure history at the port.Thus, the pressure and temperature may be considered prescribed and known, say from an interior ballistics analysis of the weapon.The hot gases expand in the bolt cavity, thereby accelerating the bolt carrier,C.Unlocking of the bolt, D, is accomplished after the carrier has traveled a certain distance, at which distance vent holes are laid free sad the gas in the bolt carrier expands to atmosphere.At this distance the bolt carrier engages the bolt and cartridge, and extraction is accomplished by transferal of energy and momentum of the carrier to the bolt and cartridge.

(The residual momentum and energy of the bolt carrier is sufficient to complete the cycle of cocking the weapon and positioning a new cartridge in the chamber.)

It is the object here to predict for a given pressure and temperature at the port the motion of the bolt carrier referenced in time to the rise of pressure at the port.The motion of the bolt carrier is governed by the pressure and temperature in the bolt carrier cavity.



This is what I have been trying to explain, the buffer-spring weight only controls the bolt carrier velocity(energy) and does not contribute to dwell time..

[Bonas]

I only use adjustable gas blocks in ARs now. Last time, I used the Strike Industries adjustable collar block. It works well so far, and I like it. I'll probably try the RifleSpeed next. Much of my shooting is suppressed.

https://www.strikeindustries.com/si-ar-cagb.html

Maybe it's irrational, but it I like the idea of excess gas never getting to the tube, so I use the block as the choke point. We're finally getting some well-designed options.