Q&A for Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver

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Primary Weapons Systems + Gun Parts Primary Weapons Systems Gun Parts Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Q&A Primary Weapons Systems + Gun Parts Primary Weapons Systems Gun Parts + AR 15 Parts Primary Weapons Systems AR15 Parts + AR15 Upper Receivers Primary Weapons Systems AR15 Upper Receivers Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Q&A Primary Weapons Systems + Gun Parts Primary Weapons Systems Gun Parts + Rifle Parts Primary Weapons Systems Rifle Parts + AR 15 Parts Primary Weapons Systems AR15 Parts + AR15 Upper Receivers Primary Weapons Systems AR15 Upper Receivers Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Q&A Primary Weapons Systems + Gun Parts Primary Weapons Systems Gun Parts + AR 15 Parts Primary Weapons Systems AR15 Parts Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Q&A Primary Weapons Systems + Gun Parts Primary Weapons Systems Gun Parts + Rifle Parts Primary Weapons Systems Rifle Parts + AR 15 Parts Primary Weapons Systems AR15 Parts Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Q&A Primary Weapons Systems + Gun Parts Primary Weapons Systems Gun Parts + Rifle Parts Primary Weapons Systems Rifle Parts Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver Q&A

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Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver

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Lare, member, from FL, United States, asked on January 06, 2026

are these post 2024 with the tuned settings for sub ammo

Answered by Lare, member, from FL, United States, on January 06, 2026

They are i did my homework the 1/6 twist rate lets you know its the latest model

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Cal, member, from KY, United States, asked on October 26, 2022

what is the barrel twist?

Expert Answer

Answered by Ethan, Gear Expert, from IL, United States, on October 26, 2022

The Primary Weapons Systems MK109 MOD 2-M Pistol .300BLK Upper Receiver features a 1:8 twist rate.

0 of 2 found the following answer helpful.

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maverickschlong, member, from WA, United States, asked on June 18, 2022

is the muzzle device pin weld or just threaded out the box?

Manufacturer Answer

Answered by Primary Weapons Systems, Manufacturer from ID, United States, on July 06, 2022

The MK109 does not come with a pin and welded PWS Triad 30, but does come with the shown muzzle device and is threaded

1 of 1 found the following answer helpful.

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JB, member, from PA, United States, asked on May 14, 2022

will the BCG of this upper work with a Binary trigger for example the fostech eco 2

Expert Answer

Answered by Ethan, Gear Expert, from IL, United States, on June 01, 2022

As long as your Binary trigger is properly installed, this Primary Weapons Systems MK109 MOD 2-M Pistol .300BLK Upper Receiver will function as intended with both semi, and binary fire.

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JB, member, from PA, United States, asked on May 03, 2022

is the BCG a m16 cut BCG

Answered by Cory, member, from SC, United States, on May 27, 2022

Yes, it is the FA/M16 cut

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JB, member, from PA, United States, asked on April 27, 2022

is this gas impingement or gas piston

Answered by Tread, member, from MI, United States, on May 07, 2022

Long stroke piston.

2 of 2 found the following answer helpful.

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Eric, member, from FL, United States, asked on April 12, 2022

Does this not have the "3 setting Adjustable Gas Regulator" like the MOD 1-M? According to PWS's site, this has the adjustable system.

Expert Answer

Answered by Ethan, Gear Expert, from IL, United States, on April 28, 2022

This Primary Weapons Systems MK109 MOD 2-M Pistol .300BLK Upper Receiver does feature the PWS Long Stroke Piston System, 3 setting Adjustable Gas Regulator.

5 of 5 found the following answer helpful.

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Cory, member, from SC, United States, asked on March 19, 2022

Does this have an adjustable gas block like my MK111 MOD2?

Expert Answer

Answered by Ethan, Gear Expert, from IL, United States, on April 28, 2022

Yes. The Primary Weapons Systems MK109 MOD 2-M Pistol .300BLK Upper Receiver features a PWS Long Stroke Piston System, 3 setting Adjustable Gas Regulator.

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Oscar Castillo, guest, from TX, United States, asked on January 26, 2021

What is the thread on the barrel?

Answered by Mercutio, member, from NV, United States, on August 14, 2021

It is 5/8x24.

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William, member, from MN, United States, asked on August 10, 2020

Hi Say does this come with a BCG ?

Expert Answer

Answered by Nick B., Gear Expert, from IL, United States, on November 19, 2021

Yes it does.

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Q&A for Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver — 20 Questions & 12 Answers

are these post 2024 with the tuned settings for sub ammo

what is the barrel twist?

is the muzzle device pin weld or just threaded out the box?

will the BCG of this upper work with a Binary trigger for example the fostech eco 2

is the BCG a m16 cut BCG

is this gas impingement or gas piston

Does this not have the "3 setting Adjustable Gas Regulator" like the MOD 1-M? According to PWS's site, this has the adjustable system.

Does this have an adjustable gas block like my MK111 MOD2?

What is the thread on the barrel?

Hi Say does this come with a BCG ?

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Q&A for Primary Weapons Systems MK109 MOD 2-M, .300 AAC Blackout, 9.75 inch Upper Receiver — 20 Questions & 12 Answers