[Lefty2Guns]

While I never made a thread for it specifically, I commented elsewhere about my bolt carrier disassembling itself after only 60 rounds. Observe...

Some info about the issue first: There's a little internal collar on the piston end of the bolt carrier (the small cylindrical object in the photo), that appears to be press fit/crushed into place (with permanent intentions I assume) to keep the action spring from coming out that end. Well that little collar popped out after three 20 round mags of bench rest/sighting in type shooting, rendering the rifle inoperable.

The fix from Kel-Tec: While I have heard of at least one other person (possibly two) having this same experience, I can report that the 4+ week wait time that they mentioned, was not the case for me at all. Firstly, I was told to send in the bolt carrier only, not the whole rifle like others. Doing so, the bolt shipped out last Monday (the 19th), they had it by Wednesday and the repaired bolt was shipped back out by Friday, arriving today (Monday) exactly one week later. I have no idea why the turnaround was so quick for me, but as you can imagine I am definitely not complaining.

More interesting, I included a note mentioning the problem and that maybe some kind of more permanent weld should be used, and sure enough the little collar appears to have been welded in place on my bolt carrier now. It's admittedly a little unsightly with the discoloration on the carrier/piston (the orange colored area that is, the end of the whole piston is darker in the photo as I applied some CLP to see if it had any effect), but if this is a permanent solution, I can live with it.

Next step is of course testing. I've got a pile o'mags and a good 400 or 500 rounds I plan on putting through it (with a good portion of that being just mag dumps) hopefully sometime this week. I'm also going to measure the collars current depth with relation to the "face" of the piston, before and after, and look for any movement.

Will report back soon after.

 

[Junkie]

If you care, you should be able to take the discoloration off with a scotchbrite pad.

Quite a bit of undercut there, not what I'd call a pretty weld, but hopefully adequate.

 

[Lefty2Guns]

If you care, you should be able to take the discoloration off with a scotchbrite pad.

Quite a bit of undercut there, not what I'd call a pretty weld, but hopefully adequate.

As far as the weld, I had to google "undercut." Assuming you are talking about that right side edge/lip, I assume that is mostly because the weld is down inside of one of those previous "clamp/crush" spots (like the other two that are still visible), so that "lip" was already there and I guess just not completely filled in like it was on the left (so does that still count as undercut in this case, and should I be concerned?).

Thanks for the scotchbrite tip.

 

[MarkB1]

Your repair looks a lot like my operating rod that came with my 037X RDB. There are the two what looks like machined indents and an area that looks like your repair without the color. The weld spot is on the top of the rod opposite the bolt carrier. Did your original operating rod have the weld spot or not? Is it possible that your original rod was missed with the weld spot in original assembly? Here are two photos of my original rod for comparison.

Does anyone else have the weld spot on their operating rod? Or not?

 

[Lefty2Guns]

Did your original operating rod have the weld spot or not? Is it possible that your original rod was missed with the weld spot in original assembly?

Very interesting. I'm almost certain it did not have that weld spot originally and would very much explain why mine failed. Thanks for the photos!

 

[MarkB1]

From one Lefty to another, you're welcome. The RDB is one great lefty gun.

 

[texcl2]

Mine has the weld too 900 series

 

[Lefty2Guns]

Mine has the weld too 900 series

It makes all kinds of sense that the weld would be the norm. I must have been visited by the QC Fairy (or lack thereof).

Gonna hit the woods on Thursday and see how she goes.

 

[MarkB1]

It should shoot good. Run it hard!

 

[Lefty2Guns]

It should shoot good. Run it hard!

That's the plan! I was pretty much all sighted in when it went "sproing!" (used the Tavor battle zero you posted in fact), barely got to actually play.

Have a bunch of portable paper/steel target stands so I can get a good mix of shooting in. Bunch of different mags to test as well.

Hopefully nothing but good to report back this next time.

 

[MarkB1]

If the discoloration bothers you try this: Lightly sand the area to remove the color and then use some Brownell's Dicropan T-4 Creme Touch-Up to re-blacken the area. I use this stuff all the time and it works great.

http://www.brownells.com/gunsmith-t...ng-chemicals/dicropan-t-4-creme-prod1109.aspx

 

[MarkB1]

delete -duplicate post

 

[sharkey]

I can't say for sure but I don't think I had that weld on my rod (ohhh behave).
That might account for my rifle crapping out on me at 40rds.

Sent whole rifle back on 8/26 and still waiting.
Emailed Sean a second time on 9/22. Stated he would check on turnaround time and get back to me but never did.

A new job might on the horizonr and the RDB could fill the role as the SHTF trunk gun...............if I get it back and it runs.

 

[Lefty2Guns]

I can't say for sure but I don't think I had that weld on my rod (ohhh behave).
That might account for my rifle crapping out on me at 40rds.

Sent whole rifle back on 8/26 and still waiting.
Emailed Sean a second time on 9/22. Stated he would check on turnaround time and get back to me but never did.

Did you disassemble to check it out before sending it in? If your action spring was sticking out the wrong end of the bolt carrier (which pretty much locked my bolt to the rear and no way to send it forward again) then it likely was the same issue.

There was another guy on keltecforum.com who's spring came out as well (he got through about 200 rounds before self-disassembly). Same wait time as you as well, last I heard, so I was really surprised when they fired mine right back at me. I believe he sent in his entire rifle too, so there may be delays related to that? I was instructed to only send the bolt carrier/spring/etc, so maybe they are realising they don't need the whole rifle (assuming this is happening to others). I also wrote "RDB BOLT REPAIR" on multiple sides of the box, so maybe someone saw that and it got to the right guy quickly?

Anyway, very much sucks this seemingly simple (and very F'ing important) QC check has been missed for a few of us, and I can't even imagine the additional waiting some of you guys are going through on top!

Here's hoping they get it sorted for you soon.

 

[sharkey]

Did you disassemble to check it out before sending it in? If your action spring was sticking out the wrong end of the bolt carrier (which pretty much locked my bolt to the rear and no way to send it forward again) then it likely was the same issue.

That was pretty much it. Calling this morning since returning my 2 email requests seems like a hassle to him. I get QC misses, it happen. Just make it right in a reasonable time frame. I thought maybe they were comparing mine with others that went out and seeing if they might recall those? Hitting my stock on the ground to get the bolt to close wasn't the intended design I am sure. It became a single shot bullpup at that point.

 

[newtothis]

Mine (Serial #Z0700 range) has the weld. Update: 10/07/2016 - Went to the range today to test fire the RDB and to sight in the Mepro 21 @ 50 yards. Fired 60 rds of Federal M855 (62 gr, green tip) with no issues. I adjusted the gas down until it would not eject/lock open and then increased the gas by 2 notches. Afterwards, I looked at the bolt carrier. It was fine. Accuracy was acceptable. Next visit, I will move to 100 yds. Update: 10/11/2016 - Went to range. Fired 20 rds @ 50 yds to verify that nothing had changed from last visit. Moved to the 100 yd range. Fired 40 rds. Did readjust the Mepro 21 to hit center mass on torso target. Rifle had no issues for the 60 rds.. Accuracy was still acceptable as I am trying to get trigger time. Looked at bolt carrier, bolt, barrel. Everything looked fine. Next visit, I will use heavier bullets.

 

[sharkey]

Just FYI, still waiting. The last email stated they would let me know when it would be shipped out. That was last week.

 

[Lefty2Guns]

Just FYI, still waiting. The last email stated they would let me know when it would be shipped out. That was last week.

Man, that sucks. I imagine the hurricane didn't help with delays (they were right in the path and likely evacuated).

For what it is worth, 800 rounds later and the bolt is holding up fine so far.

 

[rj69]

Why on earth do I get the feeling we are simply beta testing the next generation rifle that's coming out? My brand new RDB lost the extractor pin the first time out costing me ammo and frustration. Now, with new extractor pin in place, I still get random FTE problems with the gun...

Got to take my new RFB to the range today as well and guess what - FTE problems there too.

 

[Lefty2Guns]

Got to take my new RFB to the range today as well and guess what - FTE problems there too.

What mags and ammo? Also, did you adjust gas setting at all?

I was having issues with Tulammo and completely forgot to adjust gas settings during my second range trip. Took it out the next time and got things running much better. Tulammo still gave me the occasional FTE, but then I have ARs that hate the **** (seriously, we can't swear on the internet?), too, and I only shoot it for testing purposes.

All my usual bulk ammo (wolf gold, brown bear) ran without issue (brown bear needed a little gas setting tweak, too, but no failures after).

Ultimately, despite having one of the bigger issues with the rifle you can have (the missing bolt weld), I'm content with its performance now. I also went into it knowing there might be some "guinea pig" involved, so my expectations were always a little reserved.