Quoted:
So I was fortunate enough to receive a box of swag from vltor which included another matching Mur-1a upper receiver to the one I recently used on my 300 blk sbr build. I'm keeping the sbr along with a 1911, Suppressors, mags etc in a pelican case. I have enough room to fit another upper in the case which was always my intentions.

My sbr is 9.5 so I wanted the other upper to be something with a longer barrel. Originally I had planned to use a 223 Wylde to get the best of both worlds with 223 and 556 ammo since I'm already doing 300. I specially was looking at the battle arms 223 Wylde barrels in 16". I figured since I have no real intent to shoot close range with it the 16" was better over the 14.5". Is there a huge difference between the two when talking extended range of the 223 and 556 round without going to 18-20?  The muzzle device doesn't matter since I'm using it on my registered lower. So pinning and welding isn't an issue either.
 
Someone then mentioned the 25-45 sharps but I have zero intention of hunting so I have no need for a round made for small size hunting. That did get me looking into more rounds though and specially the 6.5 grendal. I understand I must get a barrel and matching bolt which it seems most quality manufactures I've found sell them as a combo. I know I also need new mags but someone mentioned you can fit them in magpul ar15 mags? Something about 5 rounds fitting at a time. I don't know if that is true as everything I read said new mags are needed.

Now I understand cost effectiveness automatically says the Wylde but I do reload so that negates round price for me. Yes it still cost a little more to make the larger round but it's still cheap enough for me as compared to buying boxed rounds. So taking that out of the factor what would be the major pros and cons of both the 223 Wylde and the 6.5 grendal. My ultimate intentions are to be able to reach out and touch someone with the upper. I did use a Geissele SD-E trigger specially for that reason. I do understand the 6.5 will shoot farther easier.

All opinions are welcome and wanted. Also any other round suggestions are also welcome. If anyone has other barrel suggestions for the 223 Wylde that's also welcome. I'm looking for something more on the accurate side but also understand I don't have a use for a proof barrel. So I'm being realistic. The battle arms seems more then enough barrel for me. So others comparable are welcome.

My last question is what are the major quality manufactures of 6.5 grendal barrels. I was looking at the jp. Are they considered the standard for the 6.5 overall? I noticed there aren't a lot of brands making them. I found a rainier arms ultra match but they are sold out. A couple on midway and brownells. Black hole etc. from most of the brands I found I felt jp would be the best money spent. Again I'm open to any and all other suggestions. I was looking at 18" in the 6.5. 20" is just a Little longer then I was looking to build on this platform. I planned to do a 308 size platform after this and figured I'd worry about longer barrels then.  

Thanks in advance for any help. Here's a couple pics.  

<a href="http://s187.photobucket.com/user/Blues2000boy/media/4E1F8BFA-3CD6-4381-860D-D441C80D30F0.jpg.html" target="_blank">http://i187.photobucket.com/albums/x191/Blues2000boy/4E1F8BFA-3CD6-4381-860D-D441C80D30F0.jpg</a>
<a href="http://s187.photobucket.com/user/Blues2000boy/media/0729745D-C659-4B7F-BCAC-320879260D63.jpg.html" target="_blank">http://i187.photobucket.com/albums/x191/Blues2000boy/0729745D-C659-4B7F-BCAC-320879260D63.jpg</a>