View Full Version : Factory RRA 10.3" uppers - barrel questions about chrome lining
I am currently doing a thorough inspection and possible overhaul of some local PD's entry carbines. (Let's put aside debate about the known shortcomings for now) During the inspection and gauging process, I have determined the barrels have what appear to be chrome lined bores but not chambers... This sounds a little out of the norm so I would like the opinions of members of the community here who have performed work on RRA carbines, particularly dealing with their barrels. I have contacted RRA and am waiting on a response. In the meanwhile here are some pictures of the chamber using my crummy iPhone camera. The last picture is of one of my uppers that utilizes a F&N barrel and you can clearly see the chrome "donut" around the chamber. I tried to capture what appears to be a chrome "donut" that is visible around the barrel throat. Thoughts?
http://imageshack.us/a/img46/1549/hvgq.jpg
http://imageshack.us/a/img842/752/49m4.jpg
http://imageshack.us/a/img707/6977/b50x.jpg
http://imageshack.us/a/img32/9414/a7nf.jpg
polymorpheous
06-30-13, 19:11
Perhaps the chambers were reamed after chrome lining.
On another note, what's up with those jacked up feed ramps?
Perhaps the chambers were reamed after chrome lining.
On another note, what's up with those jacked up feed ramps?
RRA "Machines" (read Dremels) the feedramps in after they mate the barrel to the upper.
RRA "Machines" (read Dremels) the feedramps in after they mate the barrel to the upper.
You mean sometimes, as in only when deemed necessary to remove a rough spot, or as a matter of routine?
You mean sometimes, as in only when deemed necessary to remove a rough spot, or as a matter of routine?
Nope. That is their version of M4 Feedramps. At least it was when I used to be a distributor for them.
You mean sometimes, as in only when deemed necessary to remove a rough spot, or as a matter of routine?
RRA used to only offer traditional/M16 feed ramp upper receivers. When the last big push for "mil-spec" AR's came about (shortly before the '08 elections), RRA took some flack for not offering M4 ramps on their 16" and shorter builds (which isn't a huge deal in and of itself). Instead of correctly rectifying the situation, they started using M4-ramped extensions and would (literally) dremmel their M16 uppers so that they would have "correct" M4 feed ramps (or more accurately, so they could market them as having M4 feed ramps).
This was pretty common place for RRA for awhile. They started using correct M4-ramped receivers about two years ago, but you could occasionally find some of the old style guns at various stores, especially if they were old stock.
This isn't a feedramp discussion thread...
justin_247
06-30-13, 20:24
Non-relevant to the thread. Sorry.
This isn't a feedramp discussion thread...
Maybe but it was your image which displayed the indicative workings. Anyway instead of poking at the sensible responses why not use the participation to your advantage?
The question is very specific, off topic responses are not needed.
IMHO, those uppers are not worth having, especially in duty use.
I don't know what you expect to do by overhauling them?
The question is very specific, off topic responses are not needed.
The feed ramps are an issue. Those guns have feeding problems and I would say that issue is more important than the questionable chrome lining.
Anyone who posts a response in this thread that does not have first hand experience with RRA 10.3" barreled uppers is wasting my time. Do not tell me shit I already know, I didn't ask WTF do you see wrong with this picture? Nor did I ask can someone please post a picture of a really homo M4 feed-ramp hand job. I also didn't ask if RRA builds quality guns, so give me some credit and cut the bullshit. DON'T post in this thread if you do no have first hand experience with RRA 10.3" barreled uppers and can answer if RRA only chromed the bores.
Anyone who posts a response in this thread that does not have first hand experience with RRA 10.3" barreled uppers is wasting my time. Do not tell me shit I already know, I didn't ask WTF do you see wrong with this picture? Nor did I ask can someone please post a picture of a really homo M4 feed-ramp hand job. I also didn't ask if RRA builds quality guns, so give me some credit and cut the bullshit. DON'T post in this thread if you do no have first hand experience with RRA 10.3" barreled uppers and can answer if RRA only chromed the bores.
What difference does it make at this point in time? Those uppers are junk. What do you expect to get out of them?
Nobody is trying to insult your intelligence or be disrepectful. We just aren't seeing the point in spending resources on these.
justin_247
07-01-13, 00:39
Honestly, they can probably be made to function just fine. A police dept might not have enough money to replace them with quality uppers.
He'll have to polish those sorry excuses for feed ramps to make them more functional, ream out the chambers to 5.56, check the gas port size and ensure that the right extension spring/buffer combination is used, check that the gas key is probably installed and staked, install an extractor upgrade kit and a more reliable FCG, and may need to replace the front sight post to get it to zero correctly.
Feasible... not fun, though. A sad situation.
Anyone who posts a response in this thread that does not have first hand experience with RRA 10.3" barreled uppers is wasting my time. Do not tell me shit I already know, I didn't ask WTF do you see wrong with this picture? Nor did I ask can someone please post a picture of a really homo M4 feed-ramp hand job. I also didn't ask if RRA builds quality guns, so give me some credit and cut the bullshit. DON'T post in this thread if you do no have first hand experience with RRA 10.3" barreled uppers and can answer if RRA only chromed the bores.
Really? You don't see the point in the handmade Dremel feedramps being discussed?
As a LEO, firearm instructor, and armorer (all for a long time) , I see MASSIVE ISSUE WITH IT.
Non-relevant to the thread. Sorry.
It is massively relevant to the thread, these are being used as SWAT entry weapons.
Another important issue here, concerning the ramps, is that the dremel job has removed the anodizing. Unanodized aluminum is very soft. All it takes is some wear, a rough case/round - anything to cause a surface scratch - and you can easily start having feeding issues. Murphy's law and all.
It's not just some cosmetic issue.
OP - this forum exists primarily for people who will use guns like YOU use them. Take it for what it's worth.
justin_247
07-01-13, 01:31
Really? You don't see the point in the handmade Dremel feedramps being discussed?
As a LEO, firearm instructor, and armorer (all for a long time) , I see MASSIVE ISSUE WITH IT.
I have a massive issue with it, too. I also have a massive issue with the fact that whoever ordered those guns is a massive idiot. If they lack the funds to replace them, then maybe they can be mostly fixed.
It is massively relevant to the thread, these are being used as SWAT entry weapons.
I removed it on behalf of the thread creator since he specifically complained about the post.
Let me get this whole thread back on track to where it needs to be. He knows exactly what he's talking about and he's asking a specific question for a reason. These weapons were discovered to be screwed up during my course in Georgia. The police department does not have the financial resources right now to replace these guns. Part of the inspection is to conclusively identify all the shortcomings that were observed.
Part of that process is identifying whether or not these are chrome lined chambers which we do not believe they are based on what we saw. Once this has been established he's going to compile a complete report with the other deficiencies that were discovered such as incorrect or missing feed ramps, improperly installed suppressor mounts, oversized gas ports and other issues. That report will then be submitted with a suggested or recommended course of action. They will then have to decide if they can financially afford to fix it the. Thus far the weapons have run but we all know it's a matter of time.
polymorpheous
07-01-13, 02:32
Let me get this whole thread back on track to where it needs to be. He knows exactly what he's talking about and he's asking a specific question for a reason. These weapons were discovered to be screwed up during my course in Georgia. The police department does not have the financial resources right now to replace these guns. Part of the inspection is to conclusively identify all the shortcomings that were observed.
Part of that process is identifying whether or not these are chrome lined chambers which we do not believe they are based on what we saw. Once this has been established he's going to compile a complete report with the other deficiencies that were discovered such as incorrect or missing feed ramps, improperly installed suppressor mounts, oversized gas ports and other issues. That report will then be submitted with a suggested or recommended course of action. They will then have to decide if they can financially afford to fix it the. Thus far the weapons have run but we all know it's a matter of time.
You saw the uppers personally?
Was there any indication that the chambers were reamed?
My thoughts are that the officers were getting stuck cases, probably running 5.56 pressure ammo.
They had the uppers reamed to fix the issue.
It's fairly well known that RRA doesn't have proper 5.56 chambers.
Yes as they brought them to the course. I do not believe they were reamed. They haven't reported issues as far as I know. But, they also didnt know about the stuff that was FUBAR. I was unsure about the chambers when I saw them and I didn't have time to stay out there and fix everything.
You saw the uppers personally?
Was there any indication that the chambers were reamed?
My thoughts are that the officers were getting stuck cases, probably running 5.56 pressure ammo.
They had the uppers reamed to fix the issue.
It's fairly well known that RRA doesn't have proper 5.56 chambers.
polymorpheous
07-01-13, 02:42
How do you chrome line the bore and not the chamber?
I'm not even sure how that process would work.
BTW, RRA only lists chrome lined barrel on their site.
This seems ambiguous to me.
Personally I would have not taken on this job. You would be blamed for the functional issues with these uppers but it is a situation beyond your control.
This.
It's a no win situation. This is why companies like Specialized Armament won't even talk to you about anything that's not a Colt.
Not worth the hastle. :(
The photo leads me to believe the chambers may have been reamed after the chrome process.
Do you think the chambers were reamed for 5.56mm or .223 Wylde?
The chambers have not been reamed... The chrome doesn't appear to start until you get to the bore. I will update the thread if I get a response from RRA, otherwise I'm moving on.
The chambers have not been reamed... The chrome doesn't appear to start until you get to the bore. I will update the thread if I get a response from RRA, otherwise I'm moving on.
Roger that. I am out the door.
I will update the thread if I get a response from RRA, otherwise I'm moving on.
You do that and please remember that it has been our great pleasure discussing this matter with you. Few if any have displayed your appreciation and graciousness.
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