Another buffer/retainer problem

[ott1]

I don't think so.

It looks like a bit of the tube broke off because the carrier tilt wore it thin and if you look in front of the buffer retainer pin, it looks like it might have been pushed forward a bit ovaling out the hole.

There certainly isn't enough room to thread it in another complete rotation.

As I've mentioned earlier in the thread, it's an known issue with early POF carrier with excessive carrier tilt. It has since been "remedied" with a different buffer tube and carrier. The OP should contact POF for new parts.

[duc748bip]

Posting picture of my own PWS Diabolo the buffer tube is showing wear after about 150~200 rd.



Just ordered the Improved buffer tube by PWS and their buffer. It look like its extended more into the receiver to slow the wear and the breakage of the retaining pin. I guess is another critical lube point on piston driven uppers.
With all the Diabolo in the AR pistol section, I think that is why my new PWS buffer tube is backordered...

[G38xOC]

interesting..just checked my spare field kit n it didnt come with buffer retainer . guess its nice to have for spare

[saki302]

Not to be ....

But I have been shooting AR15's since 1968 and I have never seen all the difficulties with parts/assemblies that I have seen on this forum.

That is because you are running them as designed with the original gas operating system.

When you modify something with an aftermarkt fix, problems usually arise.

I have yet to have any issues at all with a properly built DI upper.

There are many possible fixes for the carrier tilt- the easiest IMO would be to mill two slots on the sides of the carrier, and add two small shelves on each side of the rear of the upper which won't allow it to tilt at all.

I'm not sure how the big mfrs do it- maybe with tighter BC/upper tolerances? I'm curious if the HK uppers have the tilt issue.

-Dave

-Dave

[duc748bip]

Yeah I would love to see some picture of the same area on HK 416 MR556 rifles...

[mdib870]

what i think ur rifles needs is one of them fancy flux capacitors that turns back time!!

[wash]

The way carrier tilt is addressed is with carriers that have extended "skis" on the bottom rear of the carrier and buffer tubes that are extended at the bottom.

It seems like carrier tilt is worst when the carrier tilts enough to hit the front of the buffer tube and start shaving off aluminum. With an extended buffer tube, the back skis on the carrier sit on top of the extension so if the carrier wants to tilt, it has to push through aluminum (which will not happen).

It's funny that gas piston uppers create much bigger problems than the problem they are supposed to address but the carrier tilt problem can be addressed along with the bolt cam pin issue. After that they are reasonably reliable but in my experience, using good brass case ammo and running it wet with lube does more for reliability than anything else you can do.