Ruger SR-556E Rebarrel Project

[usbp379]

Back in late June or early July, I sent Marvin Pitts my Ruger SR-556E upper with the idea of shaving some weight off the gun. I like Ruger's "E" variant very much and think it's one of the better deals in piston guns on the current market. The new smooth forend is thin and comfortable and feels much better than the traditional quad rail used on previous models.

My only complaints about the gun revolve around the barrel. The profile's pretty heavy as shipped. My initial plan was to have Marvin re-profile the factory barrel but we later decided to just replace the factory barrel with a stainless steel 1x8 twist.

Well, the upper arrived today via US Priority Mail and it looks fantastic. I should've taken weight measurements before I sent the upper off to give an exact measurement of the weight shaved off. Using Ruger's website as a guide I see that the Ruger SR-556E, as shipped, is listed with a weight of 7.36 pounds. The gun now weighs 7.12 pounds. That's with Troy BUIS, VLTOR pistol grip, PWS muzzle brake and VLTOR A5 buffer tube and buffer in place. Weight without the Troy sights is 6.92 pounds. I'd guess that going back to the standard buffer tube and plain carbine buffer would reduce weight by three or four ounces.

I ran 240 rounds of ammo through the gun this afternoon with zero issues. I ran 30 rounds of WOLF, and 90 rounds of Silver Bear through the gun and all 120 rounds fed, fired and extracted without issue.

I'm very pleased with the work Marvin did. The gun looks great and feels much more balanced. Hopefully within the next couple of days I'll be able to get the sights and Aimpoint dialed in properly. I'll shoot the gun with everything from 55gr ball to Barnes 70gr TSX so get an idea of what the 1x8 twist will do for accuracy.


The gun as I originally configured it:

http://img.photobucket.com/albums/v221/tokarev/Ruger%20SR556E/P1010713.jpg

Views of the barrel assembly:

http://img.photobucket.com/albums/v221/tokarev/Ruger%20SR556E/DSC05391.jpg

http://img.photobucket.com/albums/v221/tokarev/Ruger%20SR556E/DSC05426.jpg


And with the new barrel!


Just over eight pounds with a full mag of M193:
http://img.photobucket.com/albums/v221/tokarev/Ruger%20SR556E/P1020706.jpg

The dimpled stainless steel barrel:
http://img.photobucket.com/albums/v221/tokarev/Ruger%20SR556E/P1020714.jpg
http://img.photobucket.com/albums/v221/tokarev/Ruger%20SR556E/P1020707.jpg

It's difficult to see but the the barrel's been turned to .625" under the handguard:
http://img.photobucket.com/albums/v221/tokarev/Ruger%20SR556E/P1020712.jpg

[Paulo_Santos]

That looks nice. Keep us updated.

[usbp379]

Too bad most of Marvin's work is hidden under the handguard!

http://img.photobucket.com/albums/v221/tokarev/Ruger%20SR556E/P1020716.jpg

[usbp379]

I got a little bit of range time over the long weekend and was able to put the new barrel on paper. I didn't get as much time as I wanted and it's probably going to be awhile before I've got another chance to shoot the rifle off a bench.

These groups were fired from 100 yards using my Leupold FireDot scope set on 4x.

Here's five rounds of Hornady 75gr Steel Match. The one high round was a called flier:
http://img.photobucket.com/albums/v221/tokarev/Ruger%20SR556E/P1020733.jpg

And another five shot group. This was with Hornady 75gr TAP:
http://img.photobucket.com/albums/v221/tokarev/Ruger%20SR556E/P1020734.jpg

I hope I'm not seeing a tendency for the new barrel to string vertically. Next time out I'll take a wider variety of ammo and see what happens.

[TripleBravo]

Uh-oh. Looks like it's time for a photobucket upgrade ;-)

[usbp379]

Here is my modified SR-556E with my AAC suppressor in place. The first string of three rounds is fired with the gas system turned off. The second string is with the gas on the lowest setting.




http://www.youtube.com/watch?list=HL1336184356&feature=player_embedded&v=WFF1RdKJyoE

[usbp379]

Over the course of the year since I've had the Ruger re-barreled, I've come to believe that the new barrel is easily copper fouled. When the barrel is spanking clean, the rifle shoots pretty well but after fifty or sixty rounds accuracy can drop off significantly. I've seen my groups go from a little over an inch to three or four inches (or more, in some cases) in just a short time. Cleaning the barrel with copper solvents will return the rifle to an accurate state but it is short lived.

I recently contacted Marvin with my observations and he said he's had some similar issues with the Wilson Arms barrel blanks he's been using. He says the Wilson blanks are usually pretty darned good but he's had a couple rough barrels from them as of late. Marvin was very apologetic and said he's happy to re-barrel the Ruger a second time using a chrome moly barrel blank.

Marvin's got the upper again now and I'm confident he'll make it right. I'm looking forward to getting the upper back!

[Paulo_Santos]

Over the course of the year since I've had the Ruger re-barreled, I've come to believe that the new barrel is easily copper fouled. When the barrel is spanking clean, the rifle shoots pretty well but after fifty or sixty rounds accuracy can drop off significantly. I've seen my groups go from a little over an inch to three or four inches (or more, in some cases) in just a short time. Cleaning the barrel with copper solvents will return the rifle to an accurate state but it is short lived.

I recently contacted Marvin with my observations and he said he's had some similar issues with the Wilson Arms barrel blanks he's been using. He says the Wilson blanks are usually pretty darned good but he's had a couple rough barrels from them as of late. Marvin was very apologetic and said he's happy to re-barrel the Ruger a second time using a chrome moly barrel blank.

Marvin's got the upper again now and I'm confident he'll make it right. I'm looking forward to getting the upper back!

Glad he's taking care of you.

[usbp379]

Glad he's taking care of you.


I've got no worries about this project. Marvin's machine work is fantastic. He's not at fault for Wilson's stumble with quality control.

[usbp379]

An update from Marvin. He's got the replacement stainless barrel out and is working on machining the 2nd replacement barrel to match the style/profile I want.

This new barrel is a chrome moly hammer forged blank. Once it has been machined to final shape Marvin's going to send it out for salt bath nitriding for longevity and corrosion resistance.

http://img.photobucket.com/albums/v221/tokarev/Ruger%20SR556E/DSC05825.jpg

[usbp379]

Well, I've had the rebarreled rifle back for several months and I'm happy to report that it purrs like a kitten. I haven't done a whole lot of formal accuracy testing but I did manage to shoot five rounds of Winchester 69gr match ammo into about 1.5" at 100 yards off the bench with a 6x scope.

Here's a slow motion video of the rifle in action. Note the nice consistent ejection. Gas setting is on the #1 (small) hole for this video.

https://www.youtube.com/watch?v=bup4Z8H0S04&feature=youtube_gdata_player

Sent from my Torque using Tapatalk 2