Having just forked over some hard earned money for a new 14.5", mid length gas system rilfe I'm just now researching what loads are working and NOT working well.

I"m a 20" old school fan so this is really new territory. Before you say search button, the search button only lets me go back 30 days or less on posting which sucks.

My favorite load is .223 loading with 55 grain Nosler Ballistic Tip for my huting orgasms and when have shot quite a bit of 5.56 Green Tip for misc. good times.

Should I stick with a .223 loading or move up to 5.56 one? I'd like to stay with the 55 grainers IF my new SW M&P15TS will run them reliably and accurately.

I'm already giving up some FPS with the shorter barrel so a heavier load is not high on my list..

School me?

My 14.5 middy likes hotter ammo.  It runs the mild stuff fine, but will occasionally not lock back with an H2 buffer (for reference).  I'm running an H buffer in it now.

I don't know that I've found the optimal load for the set up.... and your question is good since the 14.5 middy is an animal of its own for sure.

If you don't already have them, the purchase of several reloading manuals would be a good move if you plan to roll your own. In addition, Loaddata.com is a good resource for additional info. Though you do have to join, you can do it for less than the cost of many manuals. I can't help as I'm waiting on my supplies to start loading for my AR.

Also, for $24 you can do all the searching you want here.

The only way to know if .223 loads will function fine in your rifle is to try them.  If your rifle DOESN'T work with .223 loads, I would consider it not-fully-functional, unless you're talking about really, REALLY light .223 loads.   If you're in the middle- to high-end of the .223 load range and the rifle isn't cycling... I'd question the rifle.  Even though the dwell time on a 14.5 middy is less than a 16" middy... the manufacturer should have compensated to that to some degree by opening up the gas port a tiny bit, and I wouldn't personally want a rifle that was finicky about what it would fire, at least not within reasonable limits.

Give your .223 loads a try, and chances are that they'll work just fine.  After you've tried them, if you decide that you need a different load, then come back and tell us what you'd like to change.

Maybe a CMMG or something will be overgassed.   But I know my BCM sure as heck isn't.

I will run just about anything, but mild ammo will get some failures to lock back.  And Vltor has a special, lighter buffer for their A5 stock system just for the 14.5 middy guys.

And as a team member, you also get to use a cool avatar.  



 

Not to mention how impressed chicks are when they find out!