RMW Extreme Build. It has begun.

[mrpipesmkr]

Good news, Pablo!  It sounds like you might have solved the problem. I can't figure out what the metal flakes were but no doubt they had something to do with the bolt being so hard to move. When you look into the bore on the carrier does it appear to be smooth, not pitted or rough? As long as your rings are intact and the bore is now smooth it should function.
  Let us know how it works.

[Pablo]

It's very smooth looking now with light and magnification. The odd thing when I looked in before it was kinda of rough, .........but maybe I was in denial, assumed it was "good enough" and didn't really inspect it to start (wish I would have)

I have to think the metal (and black) flakes were in the carrier bore. I didn't physically touch anywhere else. If this doesn't completely solve the problem, I think it really puts one more item in the works better than designed column!

[mrpipesmkr]

I think that if the bolt feels similar to your other AR's and moves freely you have probably solved the problem.
  I don't know what the debri you got out of the carrier might be , I've never seen it before. Do you know if the flakes were magnetic? That would indicate  they wee steel or at least iron based. Perhaps metal shavings that were not cleaned out of the carrier barrel prior to it being chromed. Most chrome is black before it is buffed to a shiny finish. It's possible the company that manufactured the carrier just didn't get it cleaned out before finishing it.
  Of course the debri you got out of the carrier could be carbon from the discharged rounds. It doesn't seem to me that you have fired the weapon enough for that much carbon build up. It is possible that the lubricant you are using is creating the carbon when it gets hot and cookes down. You might try a different lubricant.

[Pablo]

Not magnetic, but the shiny bits and some dark bits are metallic. Some is carbon as well. I've used many lubes, and I'm sure some did coke, plus some is powder residue. I'm pretty sure with the amount of synthetic lube used some of the times, the rings rode right over the junk. Not so worried at this point, cleaned up nicely.

[mrpipesmkr]

It does sound like you've got the problem solved, as long as the bolt moves freely you should be OK.  Le us know how it works at the range!

[Pablo]

  With this thing it is indeed A problem solved. Next!   

[Pablo]

I was talking about this lube: ( not lube in general)
http://www.militec1.com/miva/merchant.mvc?Screen=PROD&Store_Code=militec1&Product_Code=BONUSPAK&Category_Code=1

frustrating for sure. The lube is above is great. You can shoot gun to generate the heat to penetrate the metal parts or bake metal parts in oven. (my wife would freak out about that part)

Update: I ordered the Militec.

I came to the conclusion the supplied rings were just junk. I made them smoother, but they were still rougher than my other AR's, PLUS compared to 5.56, and 6.8, a 10mm AR is undergassed no matter what. It has become an unavoidable statement of physics. SO, I installed JP Enterprises gas ring. HOLY SMOKES sweet with even low lube. Will get the Militec and then chute it.

The real thing here is that making a 10AR is NOT some easy project.

[mrpipesmkr]

Pablo,
  I thought I would share a write up i did on the 9x25 AR and 10mm AR I had Ron build for me. The bolt rings he supplied with both builds were fine.  I'm wondering if you got a bad round or something which blew debris into the bolt. I have found that I have to load medium hot rounds for the 10mm, especially while breaking in. It will loosen up though. The 9x25 has plenty of gas for the DI system.  I also would say I highly recommend the Quarter Cicle 10 lowers for you next build.


  I thought as long as I was logged on I would update some information on the 9x25 AR 15 D.I. Carbine I purchased from Ron Williams at RMW extreme as well as A 10mm AR I had him build. I want to give my impression of both calibers and my experience with them so that anyone considering such a build will have the info available.
  Here, I guess I have to go ahead and admit that I must be a 10mm nut!  Including the 9x25 variant I own four now and am impressed with all of them!  The flexibility of the 10mm is fantastic. With carefull work up and the right powder it can be loaded to velocities that exceed book max and show minimal pressure signs. For plinking it can be downloaded to 40 s&w velocities and maintain accuracy and function in a pistol. Throw in the 9x25 variant and you have a round that can be tailored to achieve a lot of different things.  Pretty hard to beat!
  First of all, both of my carbines are built on Quarter Circle 10 large Glock lowers. I went with this lower for both my builds because I wanted to have magazine compatibility with my Glocks.  Overall, I am very impressed with the Quarter Circle 10 lowers. They are billet machined lowers and both the machine work and the finish are excellent. They feature a proprietary mag well and mag release and are the only lowers I am aware of that have the bolt hold open on the last round. The bolt hold open is a little touchy to adjust but once it's dialed in is a nice feature.  The Quarter Circle 10 company also is one that stands behind its products. The first lower I got from them had the magazine set too low in the magwell which tended to cause feeding problems. After being informed of this problem Quarter Circle changed the design to raise the magazine and gave me a no hassle exchange of my original lower for a new lower with the raised magazine.  Quarter Circle paid for all shipping to complete the exchange, you can't ask for more than that. The new lower feeds much more reliably in fact has few failures of any kind, and I highly recommend these lowers compared to others I have seen.
  The first of these carbines I built was the 9x25 Dillon. I love its parent cartridge, the 10mm but when considering a carbine with a 16 inch barrel, it seemed that the better SD of the .355 bullet as well as its higher velocity would  make for a better all around carbine. After playing with the 9x25 for awhile and comparing it to the10mm I have to say that these considerations of mine have remained true. The 9x25 round loaded with a 125gr HP and a semi hot powder charge that I can comfortably shoot out of my Glock 20 exceeds 2000 FPS and may reach the 2200-2300 level.compared to the 10mm it is flat shooting and will still retain usable energy beyond 400 yards. I have an adjustable gas block on this AR and dialed in properly it will reliably extract brass and drop the empties right at my feet. 
  The 10mm carbine is a great rifle also, but here we are looking at pushing a 180gr bullet at 1700-1800 FPS. The lower velocity along wit the poorer SD of the bigger bullet means that this carbine does not shoot as flat as the 9x25. Going to a slightly heavier bullet would undoubtably extend the range a little but I believe it would still be limited to an effective range in the 250-300 level. But it has to be said that this round has an unbelievable punch at close range!
  It stacks up like this, for hunting, if you hunting grounds are fairly open you would prefer the 9x25 for that occasional shot were you have to reach out  a ways to bag your deer.  In brush country were range is limited the 10mm is going to bust brush better and deliver a larger bullet for a quicker kill. For hunting hogs, which is usually done at closer range the 10mm is probably the best choice. In combat situations the 9x25 would clearly give better all around performance but if you were room clearing the 10mm would be the way to go.
  Using the Quarter Circle 10 lower, both of these rounds feed reliably from 15 round Glock  magazines. I have not tried extended mags such as the Kriss's mag extensions but will in the future. Of course there is always the hope that Glock will come out with 30 round mags for the G20.  For now I don't mind using the 15 round mags as they are less awkward and it is easier to use them from the prone position.
   Both rounds, 9x25 and 10mm, cycle in the DI AR15 format with the 9x25 providing plenty of pressure due to the smaller bore. The 10mm works also but due to the larger bore must be loaded to at least a medium level with lighter bullets requiring a semi hot load. I have used Longshot powder for my carbine loads in both calibers and it seems to work well, slow burning with a good pressure curve. There are other powders which I'm sure would work in these cartridges and I hope to try them in the future although Longshot is hard to beat in a 10mm case.
  Recoil on both carbines is very manageable with the 9x25 being somewhat less than the 10mm. This is at least partially due to the adjustable gas block I have on the 9x25 but the larger bore and heavier bullet of the 10mm sort of dictates a more solid thump to your shoulder from that piece. Really the recoil on both is just enough to increase the fun and let you know your shooting something. Both are very easy to hold or return to point of aim and the 10mm with a red dot will put a series of shots on target in pretty short order.
  I'm very happy with both carbines and have had a ton of fun experimenting with them.  If your a 10mm-9x25 fan and have considered a PCC  I would suggest looking into RMW extreme  (Ron Williams) and Quarter Circle 10. You won't regret a carbine in either of these calibers.

[Pablo]

I think you are somewhat correct on thinking it's the gas system fouling. Ron says to run it dry, try as I might I can't run an AR bolt dry. What do you lube your bolt with again?

The rings under magnification looked nasty. All chewed up and rough. The bolt tail was crusty when I received it. So I cleaned and polished the tail. With the new single piece "ring" it is now SMOOOOTH. Will lube with the Militec. Probably not the cause of all my problems, but a start. I'm gonna bring  two types of ammo for the whole range trip. Start with one factory type it liked - I'm pretty sure the gun seems to like Sig. Then maybe change to one other and see what happens. Problem with some factory 10mm ammo is I don't know what powder was used.

9x25 would probably would help. And QC-10 probably is a more reliable lower, knowing what I know now. It's darn frustrating, but everyone needs a hobby!

[mrpipesmkr]

I use two lubes for my AR,s.  One is a CLP ( cleaner lubricant preservative) #S758 I got while in the military. I'm about out of it so I've been using Break Free CLP that I got from MidwayUSA also. Both seem to work OK.  The Miltec should be OK.
  I'm wondering if you need a new bolt carrier, is it smooth inside where the rings run? You might check with Ron and see who supplies his and if you can exchange.
  I will say that with the 10mm the gas port is closer to the chamber than the 9x25 so getting debris from fired rounds is more likely. I use reloads with Longshot powder which seems to burn clean. Also, my rounds aren't as hot as I can go but are hotter than factory which probably means a cleaner burn and more pressure.
  Also, I did initially have some partial feeds from new, full, Glock magazines. Forward assist generally took care of them and I attribute the problem to the action and the clips not being broken in. I'm wondering if you're longer mags arn't title enough too slow down the action?
  Let me know how your range trip goes.

[Pablo]

He says nothing wrong with the bolt carrier. I haven't bugged him for awhile. Basically he said it worked for him.

How long IS your gas tube on the 10mm? Mine is super short. The gas hole is right after the chamber.

[Pablo]

  I'm wondering if you need a new bolt carrier, is it smooth inside where the rings run?

It looks smooth, and moves as smooth as my 6.8 bolt assembly that is on my bench. It certain moves with less force than the 6.8.

[mrpipesmkr]

He says nothing wrong with the bolt carrier. I haven't bugged him for awhile. Basically he said it worked for him.

How long IS your gas tube on the 10mm? Mine is super short. The gas hole is right after the chamber.

Mine is probably where yours is, Ron uses a program to determine where to place the port to get enough pressure to run the gun.  He's done many 10mm's so he's got the location down pat.  The bore of the 10 being large means it has to be closer. But most experts will say that the majority of the powder is burned in the case before the bullet gets down the bore very far. The expanding gases then drive the bullet down the bore.  The fact that I reload may be the big difference here. My typical load is 9.6 grains of Longshot under a 180 grain bullet. I use a standard primer but have tried mag primers with this load which makes it pretty hot as the powder burns quicker. You might try reloading some rounds to see if this improves thing. If you don't reload, perhaps you know someone who does.
  Another thing to try is locating some 200 gr loads to try. The heavier bullet, loaded to the same power level usually means more pressure .  When you purchase ammo, look for the hottest loads you can get. Most 10mm you buy off the shelf is pretty anemic, more like 40S&W loads. I would suggest googling Underwood and Double Tap ammo, both of which load HOT 10mm rounds.  Call or email them and see what they have in 180-200 grains loaded with Longshot Powder.  They are good people and will work with you!  I'm only saying this cause it seems to run mine OK.
  If you don't reload Pablo, I would suggest you look into it.  It's a great hobby, cuts your cost over time, and when you get into it you learn so much about ballistics, pressure curves ect.
  Look up Underwood Ammo (the hottest, I think) and then Double Tap and let me know what you think.

[Pablo]

I do reload. And I have Longshot powder. Maybe next week I can carve out a few hours.

[mrpipesmkr]

  I'm wondering if you need a new bolt carrier, is it smooth inside where the rings run?

It looks smooth, and moves as smooth as my 6.8 bolt assembly that is on my bench. It certain moves with less force than the 6.8.

Your carrier should be OK then.
  On my previous post I forgot to mention my thinking on the hotter loads.  With slow burning powders typically used in 10mm running them at lower pressure does not give a complete burn and usually means a dirtier chamber and gun.  With slow powders upping the pressure promotes a more complete, cleaner burn.
  You may just be fighting the partially burnt powder clogging your bolt and rings. I have no doubt a hotter round will create less unburnrd powder. I suggest Longshot only because it does well in 10 mm and has been working for me in my build.
  I just saw your post that you do reload. Great! Work up some Longshot loads and see if they make a difference.