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I'm going to buy an XCR-L Standard in 300blk w/ 9.5" barrel, I understand that the gas block is buried on the 300blk. I want to also get a 16" 5.56 barrel for it. Is it worth it to get a conversion kit that changes the gas system length to their standard for the 5.56 barrel? I don't know if the caliber conversion process will be that much slower if I have to change the oprod and gas tube. On the flip side I don't know if the recoil impulse will be noticeably worse for the short gas system.
 

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I'm going to buy an XCR-L Standard in 300blk w/ 9.5" barrel, I understand that the gas block is buried on the 300blk. I want to also get a 16" 5.56 barrel for it. Is it worth it to get a conversion kit that changes the gas system length to their standard for the 5.56 barrel? I don't know if the caliber conversion process will be that much slower if I have to change the oprod and gas tube. On the flip side I don't know if the recoil impulse will be noticeably worse for the short gas system.
I have a 9.5” and have .223, x39, and .300 BLK for it, all with the short gas system. That said, changing the oprod when doing changeovers will add like 15 seconds only. Very easy! However, personally I haven’t found a quick way to pull the gas tube out (and since mine are all short system, it doesn’t matter, but I’ve considered getting a longer barrel for .223 and wondered how inconvenient it is to change the tube). I’m hoping someone will chime in with a method they’ve found for easily removing the tube because I haven’t found one!
 

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I'm going to buy an XCR-L Standard in 300blk w/ 9.5" barrel, I understand that the gas block is buried on the 300blk. I want to also get a 16" 5.56 barrel for it. Is it worth it to get a conversion kit that changes the gas system length to their standard for the 5.56 barrel? I don't know if the caliber conversion process will be that much slower if I have to change the oprod and gas tube. On the flip side I don't know if the recoil impulse will be noticeably worse for the short gas system.
For simplicity's and expense's sake, it's probably best to just stick with the 300 BLK gas length.

I honestly don't notice any difference between my 5.56 in a 9.5" bbl with BLK length gas vs. standard length in 5.56 (10.5" bbl) in terms of recoil.
 

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If RA offers a blackout length gas with a 16" 556, get one and let us know. I'm sure they can get it to run with the adjustable block and an appropriate sized gas port but my personal take is that's far from an optimum setup. Barrels have consistently been the choke point for as long as I've been dealing with RA. I don't think the op rod and tube would be a stretch to get.

Ease of removing the tube depends on the tube/ upper interface. I've had some that drop out with a couple of tap on the upper, others were tight as shit that took some creativity. For the snug ones, I've used a long t- handle Allen wrench (larger diameter is better) and inserted from the bottom into the, hopefully, exposed holes in the tube. That's given me enough purchase to gently pry or tap out the tab. For the really tight ones, I've used a bore snake or similar para cord, and got it through one of the holes, fed it back out the front of the tube then pulled it out with the cord pulling on the material between the holes. That's been an extreme case.

I need to check my stash when I get back home at the end of the week. I may have a complete 556 conversion on hand. FWIW, I can order what you want and save you some money. It won't be quicker, but it'll be cheaper. Kermit may be the faster route, he does a lot more volume than I do.

ETA: I'm going to respectfully point out that an extra 5.5" of dwell time on the 5.56 with your gas port being at a higher pressure point (than the standard) is going to differ quite a bit from the 10.5" where they went from the mini gas to the blackout which was a much smaller change in length. Again, RA may have it dialed. They change port and dial sizes without telling anyone and one of the reasons for the blackout gas length was for commonality. BUT it's another $90ish to get the setup the 16" was designed for. You do you.

EETA. The 10.x" used to use the mini gas. I think the 9.5" used to/is available in the micro gas but by going to the blackout, you increased the gas length which should be better for the high pressure round. I read Sean's post incorrectly.
 

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I think one difference, for running .223/5.56, may be that the longer gas system length may be less gassy when using a suppressor, can anyone confirm that that’s correct at least in theory?
 

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If RA offers a blackout length gas with a 16" 556, get one and let us know. I'm sure they can get it to run with the adjustable block and an appropriate sized gas port but my personal take is that's far from an optimum setup. Barrels have consistently been the choke point for as long as I've been dealing with RA. I don't think the op rod and tube would be a stretch to get.

Ease of removing the tube depends on the tube/ upper interface. I've had some that drop out with a couple of tap on the upper, others were tight as shit that took some creativity. For the snug ones, I've used a long t- handle Allen wrench (larger diameter is better) and inserted from the bottom into the, hopefully, exposed holes in the tube. That's given me enough purchase to gently pry or tap out the tab. For the really tight ones, I've used a bore snake or similar para cord, and got it through one of the holes, fed it back out the front of the tube then pulled it out with the cord pulling on the material between the holes. That's been an extreme case.

I need to check my stash when I get back home at the end of the week. I may have a complete 556 conversion on hand. FWIW, I can order what you want and save you some money. It won't be quicker, but it'll be cheaper. Kermit may be the faster route, he does a lot more volume than I do.

ETA: I'm going to respectfully point out that an extra 5.5" of dwell time on the 5.56 with your gas port being at a higher pressure point (than the standard) is going to differ quite a bit from the 10.5" where they went from the mini gas to the blackout which was a much smaller change in length. Again, RA may have it dialed. They change port and dial sizes without telling anyone and one of the reasons for the blackout gas length was for commonality. BUT it's another $90ish to get the setup the 16" was designed for. You do you.

EETA. The 10.x" used to use the mini gas. I think the 9.5" used to/is available in the micro gas but by going to the blackout, you increased the gas length which should be better for the high pressure round. I read Sean's post incorrectly.
Thank you for the considerations to think about. I think I'll go with the standard length gas system on the conversion, the $90 isn't bad. Plus I wouldn't convert calibers super often (if ever, since I'm mainly getting it for 300BLK) so the gas tube shouldn't be a huge issue once I figure out what works for my receiver/gas tube fitment. My can is a Hyperion-K which is pretty low backpressure but for general reliability's sake I think the standard gas system would be worth it.
 

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After reading Nate's reasoning....sounds like you're better off going with the standard length gas for a 16" bbl. Sorry for steering you the wrong direction. The configurator doesn't even give an option for the latest nomenclature on gas lengths ("standard short" and "mini".....which looks like it used to be mini and micro lengths respectively....with no mention of blackout length now at all) in anything other than 9.5 and 7.5" bbls.
 
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