New AR9 build

[raymond]

Time for a gun post.
I just finished assembly of a new AR9 "pistol".
I built it to carry in my truck.
It will replace my CAA MCK which is a chasis that my Glock slips into.

Here is the CAA MCK that is being retired from truck duty.




Here is the new AR9. I put the Holosun Green dot with circle and shake awake (you leave sight on and it goes to "sleep" after a certain time and you change battery once a year) on the AR9.
Anderson lower.
Sterne Defense Glock magazine mag well adapter. The Sterne defense preserves last round bolt hold open, but relocates the mag release to the bottom. Magazines drop free. Went this route as I carry a Glock 19, and wanted to be able to interchange magazines.
Rise Armament RA 140 trigger with KNS trigger pins.
Afterburner linear muzzle compensator.
7 1/2" 1/10 twist barrel.
Nitecore flashlight. M lok handguards.
SBA3 brace on adjustable carbine length buffer tube.
Heavy buffer, which I may switch out for hydraulic.
Have a ambidextrous selector on way, but not here yet.
Also bought a bunch of Glock 33 round magazines but picture is of a Magpul 27 round magazine.
Single point sling.

Functions flawlessly so far, but have not got it fully sighted in yet. Probably this weekend before final adjustments.

[m3a1]

[D Pizzoferrato]

Raymond,

Are you aware of the ATF's current move to put AR Pistols with braces into the NFA as SBRs? It seems they are going to allow a special registration with expedited approvals and will be waiving the $200 Tax Stamp fee for any AR pistol purchased or built before publication of their most recent letter on this. https://www.youtube.com/watch?v=yfDm5yfdh4Q

[raymond]

Raymond,

Are you aware of the ATF's current move to put AR Pistols with braces into the NFA as SBRs? It seems they are going to allow a special registration with expedited approvals and will be waiving the $200 Tax Stamp fee for any AR pistol purchased or built before publication of their most recent letter on this. https://www.youtube.com/watch?v=yfDm5yfdh4Q

If you read the letter, it essentially said the ATF was going to test "pistols" almost on a case by case basis and see if they could realistically be fired in the intended manner. Under such circumstances, a .308/7.62mm NATO AR10 "pistol" with a 10 inch barrel and a drum magazine could scarcely be called a "pistol". My lightweight 9mm would easily pass such a test.

But it all seems to be to no avail now, as the ATF has withdrawn the proposed rule and classification change.

I think the ATF is essentially acknowledging the horse has already left the stable.

https://www.thetruthaboutguns.com/break ... ification/

[raymond]

P.S. There are an estimated 3-4 million AR pistols out there, and I'm sure there are hundreds of thousands of other pistols based on other weapon systems.

https://www.washingtonexaminer.com/wash ... nto-felons

[raymond]

Was having some feeding problems and a case seperation Polished the mouth of the chamber, especially the bottom area. Ordered a h3 (heavy) buffer to increase time in battery and did the $1.75 solution to shorten stroke and pretension buffer spring. Shortening the stroke is also recommended to decrease the velocity the bolt hits the bolt stop and breaking it in the process.

[raymond]

The $1.75 solution involves removing the buffer and spring, dropping 7 quarters into the bottom of the buffer tube and then reinstalling the buffer spring and buffer. A blowback bolt is not as long as a locking bolt since it does not have the rotating bolt head that locks into the barrel. Therefore, when fully recoiled, the head is further back in the buffer tube and thus hits the bolt stop at a faster speed when returning. This can bend or break the bolt stop, if you have last round bolt hold open on your particular setup. Also pretensions the spring. There are longer heavier buffers on the market for this purpose, as well as custom made stock spacers that take the place of the $1.75 in quarters. Every setup is different as there is no "standard" in pistol caliber ARs. So what works in one gun may not work in another. Barrel length, weight of the bolt, weight of the buffer, bullet weight, powder charge, buffer spring, etc. can have a big effect.

My first pistol caliber AR was a Rock River Arms. At the time, I was not as well versed in them, and it was recommended to buy from a well known manufacturer as sometimes homebuilt guns have parts that don't play well together, such as pairing unramped bolts and notched hammers, big no-no. Lot more info on them online now to diagnose and correct problems as well as avoid problems in first place.

Personally, I like lightweight 115 grain hollow points. Lighter bullets travel faster, and a hollow points propensity to open up and expand is a function of how fast it is travelling when it hits.

[raymond]

Gun short cycles on Federal aluminum case ammo. Have to run the standard weight buffer with it.

May try a hydraulic buffer