[MrSmitty]

If I left out any let me know. Not sure if all these would work either. I thought since we have one for the XCR-L why not the XCR-M.

 

[dont_tread_on_me]

Very good idea but the "M" will be even further in the future.I have a few observations I hope you don't mind my sharing.OK here goes,you have a nice long list,and some very interesting choices.The problem is not all are suited to either a semiauto platform or are not feasible in the M.
First anything based on the 308 case: .243,.260.7mm-08,.338 Federal,and the .358 Winchester,are all good obvious choices for different purposes and cover a good part of the ballistic spectrum.Not to mention they all use the same bolt face,and magazine,all you would need is a barrel for any of them.The 22-250 also shares the .308 common .473 case head diameter as well so would work without requiring a new bolt.
The rimmed cartridges mentioned(45-70,30-30,.44 Remington magnum,.500 Smith and Wesson)all share the same problems,That being reliable feeding in a semiauto.Also due to case length,if the .44 mag and .500 S&W were to be considered it would fit into the XCR-L.
This one is purely my opinion,but I believe the RSAUM cartridges are on the way out.The close competition with Winchesters WSM's and market flooding,there just ain't enough demand for it.I'm not so certain about the future of the WSM's either.The .270 is the only one of those covering a possible caliber/velocity niche' that would be worth it to me.
I know the .270 Weatherby magnum falls very close ballistically,but it is a proprietary cartridge that is prohibitively unaffordable for allot of folks,not to mention ammo availability.The other problem is the R&D associated with these,because of the unusual case shape,they are not very conducive for use in semiauto's either.It can be done but it is more work.They too would also require a different bolt and magazine,making kits prices more expensive.
The grand old Ought six is too long for The XCR-M,unless designed for it which would increase cost and weight and wouldn't be worth the difference.The 308/7.62 NATO is the ballistic equivalent of the 30-06.Sure you can handload the -06 hotter in a bolt gun but in a semiauto its just not as practical as it's shorter cousin.The 6.5x55 Swedish Mauser is a darling little cartridge,every one I have ever shot was accurate as hell,but the rim diameter on it is differant the the .308 family and it's ballistically no different than the .260 Remington.So basically you would have the expense of a new bolt,and possibly magazine for nothing.I doubt that one will happen either.
The .300 Savage is another great cartridge,but it is a ballistic duplicate of the .308,so nix on that too.Although it does shares the same rim diameter,so in theory all you would need is a barrel.
This I doubt will ever happen,but I am a qaurterbore fan and as such,I think the .250-3000 Savage would make a good candidate,if it were more available as a factory loading.It shares the same rim diameter,so a barrel is all you would need.This cartridge I think could again be popular if Hornady would research it a little and use some of that new proprietary powder they have.The .257 Roberts isn't a bad choice either but I believe the case would be to long (7mm Mauser is the parent case) to use the heavier bullets in a magazine as it would infringe on powder space too much.
I hope I didn't step on anyone's toes by stating what IMHO are the practicalities of these choices.

 

[MrSmitty]

No problem about the critisim as its constructive. I just wanted to list anything I could think of that people might want. I knew many might not be possible or feasible.

 

[aziator]

I think something between a 300 and 338 would be cool, but as stated, that is probably years away.

 

[dont_tread_on_me]

I think the .338 federal would be a stomper on pigs,black bear,elk,anything bigger than whitetail that needs the extra power and penetration.Now wouldn't that kick ass,elk hunting with an XCR,hell yea!

 

[MrSmitty]

Just added the 6.5 Creedmoor to the list.

 

[aziator]

I have heard that the Creedmoor is a tack driver, need to find someone that has one and shoot it when i get back.

 

[dont_tread_on_me]

I personally think the Creedmore is pointless.It's just a modified .260 Remington case.It really is no better than the .260.It is intended by Hornady to be a Factory loaded match rifle cartridge.Here's more info if your interested
http://demigodllc.com/articles/6.5-shootout-260-6.5x47-6.5-creedmoor/

 

[dmachine]

I'd like to see the .300 Whisper more than anything else. With the 5.56 & 6.8 out of the way, now it's time for a good suppressed round. .45 ACP would be nice as well, but the .300 Whisper would have much better accuracy & range. The problem with the .300 Whisper is the gas system, it's mounted way back on the barrel to work right. I sent Alex pic's of it and how it's made so he could try and come up with a good system. We'll see.

 

[dont_tread_on_me]

This is just my opinion so don't take it as gospel.First you don't need the "M" to use to .300 Whisper as it will fit in the "L" platform.Second,depending on demand,I doubt it would be worth the time and more importantly expense of the r&d to make this work.I'm not trying to burst anyones bubble,but more mainstream calibers have the highest probability of getting manufactured simply because it will be the most cost effective.

 

[TGBTG]

I would love to have an XCR-M in 358 Win. I have a 358 Win. bolt action my father made for me from a Mauser action. It is no long range rifle but will handle anything North America has to offer under 200 yards. My buddy always razzes me because after I shoot a deer there is nothing left of the organ meat. His wife likes the liver, heart and kidney but a handloaded 225 gr. ballistic tip leaves little salvageable. Overkill I know but it stops Texas whitetail in their tracks. I would love to see the look on his traditionalist face as I headed out of dear camp with my 358 Win. XCR-M. I'd pack my Glock 20 10mm with 6' storm lake barrel and Optima 2000 reddot for those close in shots. ;D

 

[thadbme]

Texas whitetail are tiny man! When I was stationed down there they were shocked to learn that we used 7mm mags and 300 win mags up here. I even heard of some people using .17 HMR's and I was shocked...

Supposively they were saying that the .223 was the most popular rifle used in the area... I'm just saying some of those TN deer are bigger than dogs

 

[dmachine]

This is just my opinion so don't take it as gospel.First you don't need the "M" to use to .300 Whisper as it will fit in the "L" platform.Second,depending on demand,I doubt it would be worth the time and more importantly expense of the r&d to make this work.I'm not trying to burst anyones bubble,but more mainstream calibers have the highest probability of getting manufactured simply because it will be the most cost effective.

Sorry, didn't see the "M", your right about the .300 Whisper fitting into the reg. XCR. (Or any .223 / 5.56 rifle.) They did try to make the .300 W. but couldn't get it to work right. It's because the gas system need's to be mid barrel and the XCR doesn't allow this. I sent Alex some pic's of how it work's so he could understand it better. I hope they can come up with something that will work, I think it's a great round and they have had quite a few ask about it.

 

[MickeyC]

30.06 won't fit into a 308 action.

 

[dont_tread_on_me]

The grand old Ought six is too long for The XCR-M,unless designed for it Which would increase cost and weight and wouldn't be worth the difference.The 308/7.62 NATO is the ballistic equivalent of the 30-06.Sure you can handload the -06 hotter in a bolt gun but in a semiauto its just not as practical as it's shorter cousin

Been there said that. ;D

 

[dont_tread_on_me]

It might be time for a revisit of this thread for all the new blood we have here now.

 

[stanc]

First anything based on the 308 case: .243,.260.7mm-08,.338 Federal,and the .358 Winchester,are all good obvious choices for different purposes and cover a good part of the ballistic spectrum.Not to mention they all use the same bolt face,and magazine,all you would need is a barrel for any of them.

That's true of .243 Win, .260 Rem, an 7mm-08, but there's a good chance that new, cartridge specific mags would be necessary for .338 Fed and .358 Win. Although the last two also use .308 Win as a parent case, the front mag reinforcing rib will push against their fatter bullets, forcing the forward portion of the rounds toward the middle of the magazine, thereby preventing proper stacking and causing increased friction.

The 22-250 also shares the .308 common .473 case head diameter as well so would work without requiring a new bolt.

I think the .250-300 savage would make a good candidate,if it were more available as a factory loading.It share the same rim diameter,so a barrel is all you would need.

Both .22-250 and .250-3000 Savage would almost certainly require new magazines, because their cases have significantly greater taper than .308 Win. A good comparison are 7.62x39 and 6.5 Grendel, which share the same rim diameter and case length, but due to different case tapers they can't use the same mags.

 

[dont_tread_on_me]

Although the last two also use .308 Win as a parent case, the front mag reinforcing rib will push against their fatter bullets, forcing the forward portion of the rounds toward the middle of the magazine, thereby preventing proper stacking and causing increased friction

I didn't give that much thought at the time.Hopefully there would be a manufacturer that would be willing to alter the mag body profile(ribs) if they were to be offered.I don't know how much market there would be for either,but changing the magazine shouldn't be that hard.I guess the point I was mostly driving at was the bolt head diameter was the same,meaning the conversion kits would be more likely to get built without needing as much R&D and would reduce the kit cost.The whole point of that post was to give an idea of the candidates with the best chance of being considered for a conversion kit by Robinson.

Both .22-250 and .250-3000 Savage would almost certainly require new magazines, because their cases have significantly greater taper than .308 Win. A good comparison are 7.62x39 and 6.5 Grendel, which share the same rim diameter and case length, but due to different case tapers they can't use the same mags.

You are correct,The difference between the 22-250/250/300 Savage case vs the .308 family at the shoulder is .041 of an inch,and over a 20 round mag that would stack up to .82 of an inch.I did the math and there is actually more taper to the 22-250/250-300 Savage case than there is a 7.62x39,so it would most likely be a pain in the ass getting magazines to feed them vs a straighter walled case.Just in case you were wondering the 250 Savage was .055 and the 7.62x39 was .047 difference in diameter from the base to the shoulder.I hope your following what I mean here.I know your more than intelligent enough to understand,just that I explained what I meant properly.Again maybe I didn't go into quite enough detail,but like I said earlier the point of the original post was to give an idea of the candidates with the best chance of being considered for a conversion kit by Robinson.

 

[dont_tread_on_me]

Bump for new blood unaware of the poll.

 

[nyati13]

I would want an XCR-M in 8mm Mauser (if it would even fit, maybe that would need an XCR-H ;D ), but I'm sure Robarms would sell exactly 1 of those... so no return on investment.