Re: built M-4gery

Hi everyone,

I wanted some feed back regarding a build.

Currently:
[ul]
[li]bushmaster lower w/bushmaster lower parts (hammer, trigger, pins, etc…)
[/li][li]del-ton (cmt i think) flatop upper
[/li][li]cmt bcg (non mpi bolt) I restaked the bcg
[/li][li]bushmaster 1X9 chromed m-4 barrel
[/li][li]rra 6 position complete assembly stock
[/li][li]H buffer
[/li][/ul]
I am currently considering the following improvements:
[ul]
[li]BCM mpi bolt
[/li][li]cmt receive extension (buffer tube)
[/li][li]new charging handle (current one doesn’t quite close without manual assist
[/li][li]new CS buffer spring
[/li][/ul]

Question is, are the new improvements worth it?
I may have to use this weapon for self/home defense at some point. It goes along with me on camping trips and such.

Should I also consider an M4 feedramp upper and new barrel as well?

Thanks everyone,
Mortismaker (aka Mortis)

The CMT receiver extensions are mil-spec in diameter, so if you get one of those it won’t fit properly with your RRA stock. The stock will go on (because the commercial receiver extensions that RRA uses are bigger than the mil-spec ones) but it will be a very loose fit. That having been said, the mil-spec RE’s are an improvement. You’ll just need to get a different stock as well.

The M4 feedramps are a nice thing to have. If you’re shooting a lot of heavier (69-77 grain) bullets regularly, a 1:7 barrel with M4 feedramps would be a useful upgrade. If you’re shooting mostly 55-62 grain stuff, then the barrelled upper you have should serve your needs.

A new charging handle and buffer spring is no big investment. If your current spring is worn out, that may explain why the charging handle isn’t closing fully. A new bolt isn’t too expensive either, but if your CMT bolt is still fairly new I’d just keep it.

Derek

Im guessing the charging handle needs an assist because you are riding it forward. Pull it to the rear all the way to charge the weapon and let go.

Hi guys,

Thank you for replying.

The charging handle issue is weird. All the ARs I have had and M-16s I have used never had this issue. I have tried a few charging handles in this upper and the do the same thing. I can unlock the latch and move the handle back a mm or two. This is happening without moving the BCG at all. I think the latch catch on the upper must be ding or something.

Thanks for replying guys.
Mortis…