AR10 Parts Identification help

[stangguyaz]

So I called Armalite today to ask them about some extraction issues I gave them the serial number on my rifle and found out that my lower was sold as a stripped lower so my gun is a parts gun or custom of some sort. I dis assembled the rifle and took some pics of the bolt carrier group and upper I have looked online for a few hours trying to figure out what brand they are> I also own a dpms LR308 as well and its BCG fits in my upper but they don't look the same at all. I also found that it had a AR15 buffer spring in it so I ordered a factory Armalite buffer spring. here are some pics if I can answer any question about them I will asap Thanks



in this pic you can see the back of the extractor is not level with the bolt , but my DPMS is

you can see that some work has been done around this extractor

 

[stangguyaz]

Ok so I have been looking some more at pics online looks like the firing pin is Armalite from what I have seen but the bolt carrier is stumping me. Most all of the Dpms models have flat spots cut lengthwise down them the smooth sided models I have found have the gas relief holes located in the machined relief area and not in front of them. Maybe Armalite used different bolt carriers but all of their photos I have seen online show 3 gas relief holes not 2. I am going to measure the lugs on the bolt when I get home to see if the lug opposite the extractor has been relieved .002 like Armalite says theirs are. anyone have any ideas does anyone's factory bolt or upper look like anything in my pics?

 

[jasonfaz]

Carrier should be gtg. The bolt may have a larger DPMS firing pin diameter making the pin loose and the bolt face slightly different dimensionally. Might want to grab a JP Enhanced bolt with the Armalite firing pin diameter and try that as a fix for the extraction issues.

 

[stangguyaz]

well the correct buffer spring showed up today made a huge difference feels like the DPMS now. longer spring less coils much harder. After doing more research today when I got home from work i looked at the bolts and carriers again the firing pin hole in the dpms looks by eye larger than the armalite but the armalite bolt does not have the .002 clearanced lug opposite the extractor so I'm leaning towards the bolt being a dpms model and the carrier being Armalite due to the firing pin. will a armalite pin work in a dpms carrier? I also orderd a new extractor today the one in the photo has alot of filing done on it not sure why but I guess I will find out when the new extractor and buffer show up hope I get a chance to range test it this weekend or the next. another question does anyone know how to tell a Armalite barrel extension from a dpms besides the threads?

 

[arnie19]

I would get rid of that Armalite firing pin if the carrier is a DPMS .The Armalite uses a spring to hold it back and you cant put the spring on it with a DPMS carrier .I had that same set up and was getting slam fires till I put the right firing pin in.

 

[arnie19]

I had a lot of problems with my 308 upper when I first got it .The guys here shyed away from my problems when they heard who made it .I was new ,what did I know ? Any way my extraction problems were from a weak extractor spring and a very weak ejector spring .When I replaced those items it started functioning fine .My first problem though was what I think was a mixture of a DPMS carrier and an Armalite firing pin and also the first bolt head wouldn't fit in the extension .It might have been an Armalite bolt head if there different ,I don't know .I got a new bolt head and that cured the fit problem . Now its functioning fine till it started to slam fire .Replaced the firing pin when I realized it was wrong and also added a spring in the channel under the extractor where the firing pin goes so now my firing pin is spring loaded . Had it out Tuesday and fired 20 rounds through the magazine and it functions fine and a group at 500 meters just under 6 inches in diameter with 168 Nosler bullets . Needless to say I learned a lot about this rifle over the past few months .

 

[stangguyaz]

I had a lot of problems with my 308 upper when I first got it .The guys here shyed away from my problems when they heard who made it .I was new ,what did I know ? Any way my extraction problems were from a weak extractor spring and a very weak ejector spring .When I replaced those items it started functioning fine .My first problem though was what I think was a mixture of a DPMS carrier and an Armalite firing pin and also the first bolt head wouldn't fit in the extension .It might have been an Armalite bolt head if there different ,I don't know .I got a new bolt head and that cured the fit problem . Now its functioning fine till it started to slam fire .Replaced the firing pin when I realized it was wrong and also added a spring in the channel under the extractor where the firing pin goes so now my firing pin is spring loaded . Had it out Tuesday and fired 20 rounds through the magazine and it functions fine and a group at 500 meters just under 6 inches in diameter with 168 Nosler bullets . Needless to say I learned a lot about this rifle
over the past few months .

thanks I have a new extractor and spring on the way already I've replaced them once already. I will have to order an ejection spring or see if I can find one at the gun show this weekend. I am going to take it out tomorrow with the new buffer spring and see what happens with some m118 ball ammo that sticks every time. I am also gonna take my dpms bcg from the other rifle that has no issues I may try it or just parts of it to see if it gets better. I will need to order the dpms firing pin as well I greatly appreciate your input and will post my results tomorrow

 

[stangguyaz]

well I went to the range today tried shooting the m118 ball ammo did not extract 90percent of the time I put the dpms bolt from my other rifle in the carrier and it extracted 100 percent but failed to eject all the way 30percent of the time the rifle ran 100 percent through 2 20rnd mags with my hand loads it has never done that before with out issues I am going to try the extractor that I ordered if that doesn't fix it I'm gonna get a new dpms bolt