The Firing Line Forums

Go Back   The Firing Line Forums > The Hide > The Art of the Rifle: General

Reply
 
Thread Tools
Old May 11, 2010, 01:37 PM   #1
buzzkillin
Junior Member
 
Join Date: April 21, 2010
Posts: 14
Ruger SR 556 - Carrier Tilt or normal wear?

Hi all
I know this is a topic that has been beaten nearly to death, but I'm trying to determine if the wear I am seeing after about 600 rounds is a carrier tilt issue, or just normal wear, so I'd appreciate some input.

What concerns me is not the wearing off of the finish, but the fact that there now seems to be a ridge in the buffer tube directly behind the buffer sprint pin that remains raised, compared to the rest of the lower buffer tube, which seems worn down. I hope the pics describes it better:



buzzkillin is offline  
Old May 11, 2010, 01:45 PM   #2
flight954
Senior Member
 
Join Date: November 1, 2006
Location: Cypress, Texas
Posts: 933
Looks like normal wear to me. It looks as if Ruger designed the buffer tube to hadle the piston/bcg tilt.
flight954 is offline  
Old May 11, 2010, 02:29 PM   #3
buzzkillin
Junior Member
 
Join Date: April 21, 2010
Posts: 14
So, Flight, you think that the little ledge that has developed behind the buffer pin is normal? Looks like the tube has really been worn down pretty far. Maybe I'll take a sharpie and paint it in and see how quickly it rubs off.
buzzkillin is offline  
Old May 11, 2010, 02:45 PM   #4
Technosavant
Senior Member
 
Join Date: May 29, 2007
Location: St. Louis, MO area
Posts: 3,903
Carrier tilt. Definitely; you don't see that kind of wear in a DI AR. Ruger enlarged the back end of the bolt carrier to avoid that, but there's just no way to eliminate it entirely. 600 rounds is also kinda early for that kind of wear- you might want to send those pics to Ruger to see what they think about it.

Still, I'm not sure that it's that worrisome. If the wear gets too bad, just replace the receiver extension. They're $30, and on a piston AR, they should probably be viewed as consumable.
Technosavant is offline  
Old May 11, 2010, 02:54 PM   #5
Bartholomew Roberts
Senior Member
 
Join Date: June 12, 2000
Location: Texas and Oklahoma area
Posts: 5,689
It is a gas piston pushing a round bolt carrier in an upper receiver with no frame rails - the carrier is going to tilt and that is just a fact of life. The wear you are seeing is a result of that tilt.

The only question is whether that is unusual wear or wear that signals an impending function problem. It doesn't look like that to me; but I am not very familiar with the Ruger SR556. A normal DI AR has a lip that extends from the lower edge of the buffer tube and holds the buffer retaining pin in place. I don't recall off the top of my head if it has that tiny ledge in it or not as that question doesn't come up with DI ARs; but I'll take a look when I get a chance.

Is this a plinker that you can afford to shoot and watch for awhile or is this your home defense rifle or a rifle you use for work? If it is the former, I would just keep shooting it, keep a good round count on it and continue to document the wear with pictures. If it turns out the wear is normal, you've got some valuable information to share with other shooters. If it breaks, I am sure Ruger will fix it under warranty.

If you don't have the luxury of experimenting like this because you depend on the rifle, then I'd send the pictures to Ruger and see what they say.
Bartholomew Roberts is offline  
Old May 11, 2010, 03:31 PM   #6
buzzkillin
Junior Member
 
Join Date: April 21, 2010
Posts: 14
Good advise guys, thanks. At this point, because the AR platform is still relatively new to me, as is the rifle, I am not using it as my hd gun. My goto remains my AK until I know I can fully rely on this weapon, so I DO have the luxury of waiting and observing. I will most definitely be keeping a log, both of pictures to keep an eye on the progression, and round count.

For now, as long as the thinning of the buffer tube slows or stops, I am not too concerned, and as pointed out, I can always just replace the receiver extension. I'm fine with that, as long as the weapon is not doing something it's not supposed to be doing. Having unintended wear-points on a weapon can obviously have consequences other places in the rifle as well.

I have already submitted a support request to Ruger, with links to my photos, and I'll make sure to post their reply here so others can benefit.
buzzkillin is offline  
Old May 11, 2010, 03:55 PM   #7
flight954
Senior Member
 
Join Date: November 1, 2006
Location: Cypress, Texas
Posts: 933
I'm also not familiar with SR556. Did you field strip and clean the rifle before you took it out for the first time? Did you notice if the edge of the buffer tube had a 90deg. edge or did it have the ramped look as it does now?
flight954 is offline  
Old May 11, 2010, 03:56 PM   #8
Technosavant
Senior Member
 
Join Date: May 29, 2007
Location: St. Louis, MO area
Posts: 3,903
Quote:
I don't recall off the top of my head if it has that tiny ledge in it or not as that question doesn't come up with DI ARs; but I'll take a look when I get a chance.
If you're referring to the raised portion behind the buffer retaining pin, the one in the pic is the result of wear from the bolt carrier; the carrier has a channel in it to clear the pin, and obviously there's nothing there to wear on the tube behind the pin. I don't think it would cause any function issues (you'd wear the tube down to replacement before you reached that point).

From my admittedly limited experience with the Ruger and things I've read, this is on the extreme end, especially on this design.

I know somebody has developed a buffer with a "nub" on it that engages the bolt carrier to prevent tilt. Disassembly requires popping both front and rear takedown pins, since it would prevent tilting the upper off the lower (unless you chop part of the carrier, I think some have done so but I'm not sure if I would).
Technosavant is offline  
Old May 11, 2010, 04:45 PM   #9
Bartholomew Roberts
Senior Member
 
Join Date: June 12, 2000
Location: Texas and Oklahoma area
Posts: 5,689
Quote:
If you're referring to the raised portion behind the buffer retaining pin, the one in the pic is the result of wear from the bolt carrier; the carrier has a channel in it to clear the pin, and obviously there's nothing there to wear on the tube behind the pin.
Yes, it does look like there is no "ledge" behind the buffer retaining pin, which would seem to suggest that the ledge is the result of wear after 600 rounds. The Ruger has a fatter rear end on the bolt carrier that is supposed to mitigate excessive tilt. Looking at how the wear stops abruptly, I'd guess that the bolt carrier is still tilting down during the initial movement to the rear and then the fat end is straightening it out as it enters the buffer tube (but past the lip).
Bartholomew Roberts is offline  
Old May 11, 2010, 07:29 PM   #10
Destructo6
Senior Member
 
Join Date: March 18, 1999
Location: Nogales, AZ USA
Posts: 3,808
That's highly abnormal for a DI AR, even with thousands of rounds through it.

Not good, imo, and should be addressed.
__________________
God gave you a soul.
Your parents, a body.
Your country, a rifle.

Keep all of them clean.
Destructo6 is offline  
Old May 11, 2010, 07:43 PM   #11
RT
Senior Member
 
Join Date: September 9, 2000
Location: San Antonio, TX
Posts: 2,191
Tilt
http://www.snipershide.com/forum/ubb...Number=1215335
It's a know problem with Rugers
RT is offline  
Old May 11, 2010, 08:21 PM   #12
buzzkillin
Junior Member
 
Join Date: April 21, 2010
Posts: 14
RT, I read this post. If you notice, on his rifle the lip of the buffer tube has been worn down like mine, but on his rifle there is also scratching that extends up into to bt. The wear on mine seems to stop right after the lip of the bt, which indicates to me that the bolt is straightening after it's gone up over the lip. I don't know, but I'm very curious to know what Ruger says at this point.
buzzkillin is offline  
Old May 12, 2010, 04:22 PM   #13
buzzkillin
Junior Member
 
Join Date: April 21, 2010
Posts: 14
So, I got my response from Ruger. Sounds like it jibes with what I was planning on doing, which is to wait and see if the problem worsens, or evens out. The fact that the tube is not scratched further up makes me hopeful that the issue with lessen from now on, but we'll see.

Ruger's response:

Response:
1.Our patented two stage piston reduces the initial energy impulse to the carrier, which reduces the amount of tilting force during the carrier’s initial motion.
2.We have an enlarged rear diameter on the carrier, which reduces the amount of tilt.
3.We have removed a portion of the forward carrier rails, which re-directs tilting force away from the upper receiver to the buffer tube.
4.We have a radius on the rear of the bolt carrier which reduces the amount of wear on the buffer tube that might result from carrier tilt.

So, our design has less carrier tilt, has less force behind the tilt, does less damage when it does tilt, and what little force/tilt is left is directed to an inexpensive buffer tube instead of an expensive upper receiver.

Wear in the buffer tube, as a result of carrier tilt, will most likely be present to some degree in nearly all rifles. Once the wear pattern is established, it is unlikely to worsen over the life of the rifle. In the unlikely event the buffer tube continually degrades over time, the rifle should be sent back to us for review. Degradation in the buffer tube can be a concern if the top of the buffer retainer plunger (the small pin that holds the buffer in the tube) and/or the bottom of the relief groove of the carrier (which allows the carrier to travel over the buffer retainer plunger) starts to get wear.
buzzkillin is offline  
Old May 12, 2010, 05:27 PM   #14
Palmetto-Pride
Senior Member
 
Join Date: May 31, 2009
Location: Charleston, SC
Posts: 1,907
That's the nature of the beast with that piston design, but I wouldn't worry about it until it started getting into the receiver, then just replace the buffer tube.
__________________
“The problem with socialism is that you eventually run out of other people's money.”

-Margaret Thatcher-
Palmetto-Pride is offline  
Old May 14, 2010, 01:53 AM   #15
Capt Ken
Junior Member
 
Join Date: May 13, 2010
Posts: 1
Sam problem

i had such bad carrier tilt it wore the tube down to failure and the pin flew out so i sent it to ruger and they said they are going to replace the whole gun it should be there now but iam on my ship and wont be home till june we will se haow the new rifle works.
Capt Ken is offline  
Old May 15, 2010, 12:29 PM   #16
buzzkillin
Junior Member
 
Join Date: April 21, 2010
Posts: 14
Thanks again for all the feedback guys. I feel like I've a sufficient understanding of this issue now.
buzzkillin is offline  
Old May 17, 2011, 11:43 AM   #17
daf3625
Junior Member
 
Join Date: May 17, 2011
Posts: 2
Carrier tilt is real

Got the same prob, Ruger says send it in and they will fix it

Last edited by daf3625; May 17, 2011 at 02:11 PM.
daf3625 is offline  
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 02:59 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2014 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.10908 seconds with 7 queries