Robinson XCR barrel length change?

[BL]

Has anyone had an issue with the fact that there is no ejection port cover? (i.e. dirt and grime?) I'm almost dead set on this rifle at this point ... my biggest dilemma is trying to decide which caliber.

 

[Dr. Tad Hussein Winslow]

It doesn't need a cover - it's a Kalashnikov, fercripessake! (essentially). Dunk it in mud and it will fire then yell "Thank you Sir, may I have another?!"

 

[Marcus L.]

The M16 series is the only common semiauto/fullauto that uses a dust cover. As PremiumSauces mentioned, the AK series of rifles doesn't use one, nor does the M1 Garand, M14, H&K G3, or the FN FAL. There's plenty of war stories with most of those rifles and hard use in all kinds of nasty environments.

The dust cover only really protects the rifle when it is not in use. Once any firing begins, the last thing you worry about is putting your cover back up between shots. It helps the M16 series stay less gritty, but then again the M16 bolt assembly is more sensitive to dusty environments than the XCR bolt assembly design. During the Army extreme dust environment testing of 2007, the M4 had almost 900 stoppages in 60k rounds while the other competing rifles like the FN SCAR and H&K XM8(with no dust covers) only had stoppages between 150-250 times. The bolt assembly design is of more importance for good reliability than a dust cover. The XCR's reliabilty is on par with the SCAR and XM8.

 

[BL]

I knew the XCR operated differently but I didn't realize it wouldn't affect it at all.
Granted while firing the cover will be open anyway, it's been drilled into me that once you're done firing to close the cover to prevent the sand and other particles getting in there.

 

[Marcus L.]

... my biggest dilemma is trying to decide which caliber

This link might give you some insight on your choice:

http://www.dtic.mil/ndia/2008Intl/Roberts.pdf

Given all that we have learned in the last couple of decades, the 6.8 SPC is the most advanced assault rifle cartridge to date. Out of the 5.56 NATO, 7.62x39, 5.45x39, 5.8x42, and the 6.5 Grendel it has the most reliable and effective terminal effects and is the most versitile with bullets ranging from FMJ, to OTM, to bonded expansion loads. It is the only cartridge of those that will pass FBI protocols using fragmenting OTM, and the only one to reliably upset and fragment in FMJ form while still passing all FBI protocols. This is due to better fleet yaw, better angle of attack with its more triangular bullet profile, and optimal sectional density. I talked a lot about it in this thread:

http://www.thehighroad.org/showthread.php?t=396783

It's always good to have a 5.56 rifle on hand, just as it's good to always have a 9mm handgun on hand. If we lived in Eastern Europe, then a good 5.45x39 or 7.62x39 rifle and a 9x18 pistol would be in order. My XCR is chambered in 5.56 and I feel confident with it provided that I use effective ammunition like OTM or soft points. If you have access to OTM and SP ammo, it is superior to the 5.45x39 or the 7.62x39. However, I would like to upgrade it to 6.8 SPC when I get the chance as I feel it to be a superior round. Silver State Armory has the best 6.8 SPC ammo right now which is full power:

http://www.ssarmory.com/

The only downside to 6.8 SPC is that there isn't really any cheap practice ammo available at this time, so if you want a lot of practice time you'll need to have a fat wallet or reload. As the 6.8 SPC becomes more popular you'll see much cheaper practice ammo.

 

[variablebinary]

Has anyone had an issue with the fact that there is no ejection port cover? (i.e. dirt and grime?) I'm almost dead set on this rifle at this point ... my biggest dilemma is trying to decide which caliber

Non-issue. Consider the SCAR doesnt have one, or the dead XM8 (extreme dust test winner), or the Bushmaster ACR/Masada, and of course the Robinson XCR

In fact no gun made recently has a dustcover with the exception of the 416...which at its core is just another AR15 and the 2nd worst performer in the extreme dust test.