Range Report Ruger SR-556 Carbine

[zombie237]

Ze, I saw your pictures and it reminded me of a question I had for you. After firing my first 1,000 rounds, I took the rifle apart as far as I could get it and on the bolt carrier group, I found the bolt assembly what looked to be shards of metal shavings. I was unsure if this was the chroming coming off but when I bought it, it was chromed, when I fired and cleaned, the bolt assembly had the orange ring pictured in your last photo. I cleaned all the shavings away and have not had any issues since after then next 1,000 rounds.

I’ve been saving before/after pictures of the “carrier tilt” problem areas for future review, but to the unaided eye, I don’t see a difference from purchase to 2,000 rounds later. I’m looking to put the pictures side by side and with the help of a few computer photo programs comparing the photos. I’ve found setting 2 to work well for anything I put through it, but need to find more research on the settings to better understand them. My only real issue was 2 out of 2,000 that didn’t feed and when I conducted jamming drills, I kept the two rounds. There were gouges on the round’s tip about 1/8th to 1/4” from the tip that I was worried was a ramping issue but after firing more, it has only been those 2 to date.

Cleaning is basically wiping off and that’s it for me really. Every time I go out I get 1,000 rounds of different ammo to try them out. So far, the first 1,000 (of which had both jams) were Federal .223 from Wal-Mart and the 2nd 1,000 were Monarch .223 with no feed issues. This next time, I’ll be looking for the next 1,000 of a different manufacturer to see how well they work. Thanks again for all your info on the Ruger. I really enjoy the rifle and your explanation helps understand the piston system a bit better.

P.S.- I found the shavings around the back side of the bolt assembly in your last picture and in taking the assembly apart they were also under the tab you remove when taking out the tiny retaining pin that holds the 2 pieces together.

 

[ZeSpectre]

I've found a few little shavings as well. I think they are coming from the channel that the cam pin rides through in the bolt carrier (hence my interest in a POF "Roller Cam" pin).

If I have time maybe I'll pull it all apart and examine more closely.

 

[zombie237]

Ze, recently ordered a replacement flash surpressor for the 556 initially for cosmetic reasons, but since our discussion I was curious as to potential mechanical/firing changes of a new flash surpressor. I'm going to research now, but wondered if you'd heard anything regarding this type of change. And I wanted to ask, in your picture, what are those short straight mags you have? Who are they made by and how do you like them? I need a few more than the 3 I was "issued", thanks.

 

[ZeSpectre]

I doubt that a flash suppressor change would make much of an alteration in the internal barrel pressure so I don't think it would affect operation.

The straight mags are 20 round Magpul Pmags. "Little brother" to the 30 rounders that came with the gun.

The shorter 20 round mags are a LOT more convenient when sighting in the gun on a bench.

 

[flight954]

(hence my interest in a POF "Roller Cam" pin).

I just took a trade POF upper with a roller cam on the BCG. I haven't been able to shoot it yet. The guy I traded said it was shooting sub MOA at 100 yards. I guess I'll see.

 

[zombie237]

Ze, I got my Troy parts in for my Ruger, I'll get pics this weekend as for the flash surpressor I'm going to need a bit more to change it out. I also received the reply from Mike Panonne who wrote the article we spoke of before on his 2 cents regarding piston upgrade for reliability/accuracy.

This is what I sent and received:

Mr. Pannone,

I was wondering if you could address an issue I have. I read your article on the M4 fouling issues and how your field test replaced the buffer spring and other drop in parts. My question is would these changes apply to a gas piston driven M4. I recently purchased the Ruger SR 556 and have had no real issues with the rifle and am satisfied completely to date. My curiosity stemming from your article makes me wonder if the reliability of the rifle could be improved with the parts you described in your article or for a gas piston rifle does it not apply. I would love to increase the reliability and accuracy of my rifle and have purchased aftermarket parts to potentially increase accuracy but based on your article, would a few drop in parts improve the reliability of my gas piston driven rifle. I appreciate any insight you might be able to offer and I really enjoyed your article.

Dustin

Reply Received:

Dustin,

The recoil impulse is different on a piston gun vs. a direct gas version. If the gun is running good and you are happy with the recoil characteristics, I would always put a 5 coils extractor and/or an O-ring to go along with that. Since there is a single impulse of energy transmitted via the piston vs. a pressure spike and follow on wave (as the bullet passes down the barrel and gas is tapped from the barrel) piston guns have a more violent extraction and faster bolt speeds. If you try to spring it and weight it heavy without testing it at odd angles and with little mass(i.e. your body) behind the rifle you can run into short cycling issues. For that reason I would refit the bolt and use a good lube. Since it’s a piston gun the lube will last a long time as long as it is synthetic (it won’t evaporate in dry climate with summer heat.)

I have 2 LWRC piston guns and though the gas system length is the same, they use different buffer springs. Since I shoot quite a bit I tune all my guns to the best buffer and spring weight for the softest shooting and most reliable configuration. That is just a function of understanding the recoil dynamics and having the time to test it.

I hope that helped,

Mike



PS If you run a closed bottom flash hider on most piston guns, because of the way the recoil is transmitted to the bolt carrier the muzzle will actually go down when fired. If you notice this just put on an A1 style flash hider (military A1 version, VLTOR VC-1, VC-A1, Phantom 5C-1 or 5C-2 (open bottom) or a Vortex and it will remove the problem.

 

[ZeSpectre]

Good info, thanks for sharing. I was especially intrigued by this...

PS If you run a closed bottom flash hider on most piston guns, because of the way the recoil is transmitted to the bolt carrier the muzzle will actually go down when fired.

Logically if one works through the physics of the gun it does make some sense that it might happen that way.

 

[Uncle Malice]

ZeSpectre,

Thanks for the great review. I have an SR-556C on order. Should be here by end of week or early next week. I was looking around for some cheaper optics and was looking heavily at the Burris Speed Dot red dot for just under $200.

After reading your review and seeing your photos, I went ahead and just ordered the NC scope that you have here. Found it for $92 on Bud's. Certainly reasonable enough for me to have some range fun with.

If you still have your SR-556, how is it holding up? I realize this thread is about a year old; so I think it would be great to get an update on your gun is running. Any new observations about the gun, good, bad, or otherwise?

 

[ZeSpectre]

Hi Uncle Malice,

As any of my friends will tell you, I'm far more of a pistol guy than a rifle guy so the SR-556 hasn't gotten the workout it might from some folks

Still we are somewhere in the 1,000-1,200 round range and I can tell you that I'm just as pleased with it as when I bought it.

Accuracy is great. My rifle seems to work very well with Federal Lake City .223 / 5.56 XM193 55gr. FMJ and for some reason it REALLY shot well with some Privi ammo that I had.

Stupidly, I didn't write down the specifics of the Privi ammo and have since forgotten exactly what I had which is a little frustrating because I'd love more.

I'm still trying to dial in accuracy with my reloads. Groups are tightening up but I haven't found the perfect combo yet.

Mechanically the gun still looks brand new. There was a little initial "break in" wear in a few of the usual spots but since then I really can't say as I've seen anything additional of note.

I did pull off the adjustable stock and put a traditional solid on one. Maybe less versatile overall but it works better for me.

I'm not sure if the trigger has "broken in" some, or if I've just become used to it but we are getting along better these days. Still hardly the best of all triggers but it is consistent and for me that's really what matters the most. If the trigger is the same every time then I can adapt.

 

[Uncle Malice]

Thanks for the update.

I'm definitely more of a pistol guy as well. This is actually my first rifle, so we'll see how it goes!

The trigger is one of the only complaints I have heard about the SR-556. Many people say that they would rather drop in a nice two-stage. I'm not familiar with rifle trigger, so I'll give it a shot and I can always replace it if I feel the need.

I am also eyeballing a different stock. I'm primarily looking towards the Magpul MOE style.

I'm probably going to be ordering some of the XM193 as well. ATG has some for a fairly decent price right now. I've heard that these guns don't really like to run with Wolf, but AIM has some for under $4 a box - so I went ahead and ordered some to see how it runs with it.

Cheers.

 

[ZeSpectre]

Yeah...I tried some wolf in mine just for giggles. Accuracy was terrible but again that may just be MY specific gun so I'd love to hear how it works for you.

 

[bravo124]

ZE. Thanks for the great review. I love mine and will try to get some pics up if I ever become computer literate. Unfortunately, I live in the communist state of New Jersey and have to have a fixed stock. Also, Ruger sent me the one without the compensator since it's New Jersey. (Can't say Flash Suppressor. It's like saying Bomb on an airplane!!). Anyway, I use setting #2 on my regulator. It seems to work the best for me. Do you use the same setting? Have you tried the others? Thanks again. Joe.

 

[Uncle Malice]

Just got back from the range after shooting by SR-556C with the NCStar.

My local range only goes back to 75', so I couldn't zero the scope out to 100 yards. This is from 25 yards, just resting on a table top, no real bench rest available to use.

Here are my results after spending 37 rounds on getting the scope zero'd and then 23 rounds into this target.

Shooting 55gr PMC FMJ - could be a little better if I would've slowed down a little. I got a little sweaty eye'd and sent those three flyers.

Regardless, I really, really like this gun. It shoots great, seems pretty accurate. I've not had a single failure to date and that includes about 350 rounds of Wolf and 200 rounds of PMC. I would still like to put a Magpul stock on it and I also want a single point sling - and maybe a front grip. Other than that, I'm very happy.