hi i am new to this and am building an ar 15 7.5 pistol. will a standat=rd car buffer and spring work in this barrel length? thanks.

Used to build AR pistols when they first came on the scene 15years ago. Tried to make do with the rear buffer assembly sold by Model 1, M and A, and Gunsmoke. None worked to my satisfaction. Those 45 pistol recoil springs never held up to the violent force placed on them by the AR bolt carrier. A very high cyclic rate. Not even the Wolfs...(.and I used 18 up to 25 pounds in my testing ) could sustain more than a few mags before giving it up. And that little buffer they all used, couldn't keep the bolt from bouncing back. Purely, not enough mass to steady the carrier assembly after chambering the next round.

There were also many problems were with the gas port diameter and its location on the barrels. The AR needs about 4 inches of barrel in front of the gas port to function. This DWELL TIME is critical for proper extraction and good ejection. Unless you enjoy constant jams!
At first, the gas ports were coming out undersized for the short rear ends and that didn't work. But by drilling out the port and installing an adjustable gas port fixture, you could then tune for the exact amount of gas volume and pressure,each weapon needed to cycle.

A modified CAR buffer tube with the bottom machined smooth (and round), allowed me to then use a CAR buffer and spring combo. No more bolt bounce.

You'll also need a genuine Smith Vortex to tame the muzzle flash. Don't believe me? Test with a regular GI A1 or A2 about dusk. You'll soon SEE why. And be sure to wear a long sleeve shirt....unless you want to burn your forearms.

Peace out.

I found that a 4X40 NC tap works with existing hole diameter. Ran tap in deep enough for short 1/8 inch long allen set screw available at any hardware store. .050 inch allen wrench required. Check function of take down pin. I needed to shorten spring one coil. Recomend thread sealent on screw for future ease of removal. Works well for oh sh*t factor.

Originally Posted By PaladinX13: http://i20.photobucket.com/albums/b230/jonoboy/IM002020.jpg http://i20.photobucket.com/albums/b230/jonoboy/IM002015.jpg Can someone identify this buffer tube (or buffer tube cover) for me?

It appears to be a pistol buffer tube with a CAA Buttstock saddle strapped to it. Interesting idea. I'm curious as to what was used to secure it to the buffer tube.

I had the gunsmoke-type buffer tube and spring. Lots of forward assisting prior to putting the ACE on there. 7 inch barrel. With the full carbine ACE tube originally I was getting some short stroking. Clipped 3 coils from the buffer spring. 500 rds later it hasn't done it since.

I plan on buying another carbine buffer and spring to see if I can cut that down and make it work with my shorter buffer tube, but I'm partial to the ACE at this point.

Originally Posted By Big-Bore: Don't forget the Bushmaster pistol type tube. Longer than the old Model One but shorter than the Entry. It uses a modified bolt carrier and from all I have heard on here it is as reliable as longer Entry tube and standard size BC.

Anyone have part numbers and prices for all that is required to do this? I'm getting ready to build my first pistol and this seems to be the way to go to get the best balance of length vs. reliability.

Originally Posted By Parabellium: has anyone tried the gunsmoke buffer setup?

I have a Gunsmoke and it works great.

Does the Gunsmoke buffer tube use a standard bolt carrier? Thanks in advance.

I have something very similar to the Gunsmoke pistol from Chester Arms http://www.chesterarmsllc.com/Handgun/AR-15%20Pistols.htm and it works flawlessly. 7 1/2" barrel, 4" buffer tube. After about the first 30 rounds and a good cleaning it has fired over 300 rounds with no problems. As fast as you can pull the trigger it will pile all the brass right in a pile about 3' ahead and at about 1 o'clock to the shooter. Definitely needs a better flash hider. there is a 18" ball of fire exiting the barrel. It is the most fun you can have with an AR IMHO.

Why would he go to jail? That isn't a buttstock, it is simply a pistol buffer tube with a battery compartment on the side. You can't use that against your shoulder.

If you use a "pistol" tube created from a CAR tube that is smooth (i.e. no stock position lug holes in the bottom side), then you are OK because a normal, off-the-shelf CAR stock will not work. I beleive this is what Model 1 Sales sells now as their "pistol tube/buffer". The ATF concept that you all have been dancing around here is "constructive intent". This is ATF's terminology and their logic - not mine. Don't shoot the messenger.

As for "face slap" (muzzle blast hitting you in the face), the solution is a muzzle device that forces the blast forward (down range). I have had good results with the DPMS Muzzle Brake Levang Linear 1/2" x 28 Thread AR-15 Pre-Ban Steel Matte (MidwayUSA sells them - $32.49 - at http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=524840&t=11082005)

You first have properly ID the hole you're referring to. The hole for the safety/selector detent and spring exit from just above the pistol grip housing. That small hole in the top of the grip holds the spring which presses up and on the detent engaged with the safety and or selector.

It is the rear take-down pin spring and detent that exits from the rear of the lower reciever and is held in place by the rifle buttstock or end plate from a carbine stock.

the fact no one noticed this error leaves me to doubt the technical skill you guys possess.