I'm still beating my head against the shooting bench with this turkey. I was having nothing but jams and I finally traced it to a poorly formed extractor and a sticking ejector. I would have changed the whole bolt but the kind folks from Pro-Ord. made sure their bolt splines were enough different from the mil-spect that only theirs would work. And they're out of biz. So I robbed another bolt of the needed parts and hoped for the best. Unfortunatly on the first mag the rear of the plastic buffer tube blew out. Meanwhile while I wait for Bushmaster to get going with their parts dept. JB weld to the rescue. I hope. Here's the question: It looks like there should be a shock absorber like a soft plastic washer on the end of the buffer spring weight that hits the end of the buffer tube. The weight has a partially threaded protusion. Anybody been down this road I don't have a complete parts breakdown to see if there actually is a washer called for. Meanwhile I think I will make something to fit, maybe a garden hose washer. Or a thick 'O' ring.Thanks for whatever advice you might have. Mikke

Mikke,

Yes, there should be a rubber ring somewhat like a bolt buffer like you would use in an AK, FAL, etc. Someone must have removed and lost this prior to your ownership, I would suggest trying different car rear brake cylinder seals, they are cup shaped similar to the guns original. When you find one that will slip easily (or with minor friction) into the buffer tube and make a hole in the center that will slip over the buffer tube pin using a gasket punch , etc. This will restore your rifle to proper configuration, however with the damaged buffer tube it may be a moot point, keep a close eye on it.

I have read several posts where members here have modified standard bolts to fit, the edges of the locking lugs need to be slightly radiused on the square edges like the PO bolt. The best way I can think to do this is using a Dremel tool with an emory cuttoff wheel, these make exceptionaly fine cuts and will polish using the sides and with a light touch will not overheat the lugs ruining the heat treatement, GO LIGHTLY! take off small amounts at a time and keep it cool.

Have you tried to de-burr or polish the appropriate areas in your existing bolt? this may allow the ejector and extractor to function properly with much less work.

Keep us posted, I have a type 97 that fortunately runs like a swiss watch, first AR I have ever shot that actually kicks!

Jeff

JKH    
Thank you for the clear advice on fixing my Carbon-15. I know just what you mean about using a 'cup' shaped like the one used in the rear brake seals of a car. Finding something with the correct thickness so as to not shorten the stroke of the buffer too much while still providing sufficient shock absorbtion  may be a trick but it's a place to start while I wait for Bushmaster. Let me run my idea about a temporary 'bandaid' for the JB welded buffer tube end. I think I will cut a dowel rod about the same thickness as the buffer tube and use that for a spacer to support the repaired end. The dowel rod will butt on the inside bottom of the stock and give needed support to the repaired tube on the other end. I will probably attach  thin rubber pads to the ends of the dowel where it makes contact. Watta ya think? Mikke

There's enough wrong with that model that I think Bushy is going to play hell getting it working right.  I was offered one but RAN.

Mikke,

I was told by another Carbon 15 officianod that Radio Shack sells and adhesive that is perfect for carbon fiber materials, probabl can buy something at a hobby shop for RC planes that would work well also. I think a spoecialised adhesive will work better than the JB weld mostly because you will have limited clearance in the stock tube for the buffer tube, by time you sanded or filed the JB down to fit the joint may be too weak. It certainly cant hurt to try either.

T2, all of these rifles are not problematic, from what I have read probably no more so thatn a standard AR. In fact, overall I would say these were built to much higher standards of fit and finish than any other AR. Of course you will get bugs with any, the troubles hooting board seems to have plenty.

JKH, Re: Carbon-15. Well, I used JB weld on the broken buffer tube and made a buffer shock absorber out of a rubber/fiber ring which I then glued to the end of the buffer. You are right about the tight fit in the stock tube, I had to sand off a good deal of the weld before I could get to fit. Anyway I took it to the range this morning and first shot it seperated again. I'll give the radio shack glue a shot next. I wonder about the depth of the buffer shock absorber ring. The ring I am using extends the buffer about 3/16" of an inch. With the gun assembled the bolt/carrier locks back O.K. But it's tough to tell without specs or a lot of experiment what the buffer spring compression should be in relation to buffer tube depth. In other words if the spring compresses completely because the buffer is now too long, when run back it puts too much pressure on the end of the buffer tube. Oh well when I get tired of working on the carbon-15 I grab my SP-1 Car and put a few hundred trouble free rounds through it. Thanks again for the info. Mikke

Mikke,

I will pull mine apart tonight and check the thickness.

Jeff

JKH, I tried the best plastic glue I could find to fix the buffer tube but it came loose after 3 rounds. I guess I'm stuck until I can find a new tube. Mikke

Mikke,

That sucks, I will try to brainstorm something for you but it looks like you are temporarily SOL.

Jeff

P.S. sorry I didnt get to pull mine down last night, I found out the dangers of using a Dremel fiberglass cuttoff wheel without safety goggles, and spent most of the day between urgent care and my opthomologists getting a piece "drilled" (literally) from my eyeball where it had embedded.

JKH, I'm sorry to hear about your eye problem.  Safety goggles are sure worth the minor cost and/or time involved to find them. As far as the buffer tube problem is concerned I'm at a loss. I thought of cementing a small metal liner to the bottom 3/4" of the tube (inside) to give more meat to glue the broken end piece to but because of the close tolerances inside and outside that won't work unless I take some metal off the buffer. Sheathing the outside would work but then I would have to enlarge the inner stock to fit. Neither idea is failsafe so I guess I'll wait and  hope Bushmaster retros a better tube, hopefully metal. Mikke