RRA won't answer me

[denniscalhounhare]

After reading Robs's "Oh No! I bought a BM/RRA/Stag before I knew better!" and several other variants, I began wondering if my upper rail on my RRA Varmint is milspec. Anyone know that answer?

Trying to determine if return to zero is possible if I put glass on top and switch scopes between my RRA Varmint upper and a different CMMG upper.

[LOKNLOD]

What mount would be holding the optic? I think that will have greater effect on the ability to return to zero than the rail itelf. You'd be best served with a Larue or ADM mount if you're looking for return-to-zero repeatability.

Another note, are you saying you plan on moving the same optic between two uppers, and are looking for it to return to zero on each one?

[Dave L.]

Have you ever tried to go back to a Car Salesman, they forget your name the minute you drive off.
RRA could give a shit IMHO.

Like was said above, should be your mount that matters on the return to zero- not the upper rail.
If your rail was out of spec that may just mean that mounts designed to fit "mil-spec" rails wouldn't fit properly.

[Dogface]

RRA refuses to answer your question or RRA doesn't answer the phone... two entirely different issues there. Good luck getting thru to any dealer or mfg these days.

[David Thomas]

Trying to determine if return to zero is possible if I put glass on top and switch scopes between my RRA Varmint upper and a different CMMG upper.

That is not a "return to zero" issue in my opinion. Various uppers will shoot to different points of impact regardless of rail deminsion. Switching scopes between two uppers without re-zeroing the optic on the new gun is not a wise move regardless of who makes the gun or upper.

Return to zero is when you take the optic off of one gun, for whatever reason, then put it back on that same gun without a shift in poa/poi.

[denniscalhounhare]

The fact that the RRA rail is not milspec is my main concern as no matter how good the mount, I may be outta luck getting my fine mount and glass to lock into place at the exact point every time. Larue is just up the street from me so I could go ask or bring in the rifle.

My plan is to purchase a Kahles Multi Zero scope to switch between my RRA Varmint for shooting little things far off and my pending CMMG 6.8 SPC upper for shooting lots of feral hogs a long way off. (Don't pass judgement. I have my N4 Basic to defend me in case of civil unrest or a Mesoamerican invasion.)

From what I understand, the Multi Zero will allow you to dial in one caliber at multiple distances, or you can have multiple calibers at the same distance.

If this is the case, I will sight in one of the setting on the RRA for 5.56 @ 200 yards. After switching the upper and reinstalling the scope, I will select another setting and sight in the 6.8 @ 200 yards. This is an expensive experiment, but will the facts and parts fit the theory?

[Dave L.]

You don't have to be worried about the receiver rail so much. Relax. The uppers RRA uses, I believe, do not have feed ramps until someone cuts them in with a rotary tool. The upper rail should be fine for shooting out to 200.
If you are really that worried about it, get a mil-spec upper- or sell the whole damn RRA upper and order a Noveske.
just my 2 cents.

[denniscalhounhare]

Already have a Noveske for play time and defending The Republic. I know folks rag on the RRA's, but for what I bought it for, it is a fine friend.

We have a lot of guys in TX that drive one ton diesels and have never gotten them dirty. Same goes for AR's methinks. I am of the camp that there is nothing wrong with some of these non milspec guns, but if I had to stash one in a swamp for a few months to hide it fromt he powers that be, I bet my RRA would return to the Earth, and my Noveske would continue to serve....

Just wish I knew more about the compatibility issues before I wound up with so many guns. Too many guns is a real problem.

[chadbag]

RRA and Daniel Defense use the same forgings on their A4 type uppers. They both have the keyhole mark (at least the samples here do). The upper rail will be as "mil-spec" as any. The RRA uppers do not have the M4 feedramps in them.

[Dogface]

The RRA uppers do not have the M4 feedramps in them

My RRA Entry Tactical has them, no, I didn't buy it used.... unless of course I have no idea what I'm looking at

Based on this image, it has them. To date, I'm not convinced I care however.
(mine match closely the 2nd from the bottom/right example)

http://www.ar15barrels.com/gfx/feedramps.jpg