300BlkTalk

Hi...

Bought a 16 Factory NIB upper in 300 Blk. The recurring case mouth deformation is obviously consistent. The Left group of cases that were fired for load development and the right group was factory ammo and a different case...



Anyone KNOW the cause of this...?

S/F

I've been here for years and nobody has ever mentioned anything like that.

I havent ever seen anything like that.

SEARCH "dented case mouth" and have fun reading for days.

Some options we may want to think about:

bangbangping wrote:Some options we may want to think about:

Now now he's only been a member for 5 years you can't expect him to know everything
And with a name that starts with jarhead he may have been in a foxhole for the last 4.

who is the manufacturer of the upper? I would probably start by contacting them with the problem and ask for their input.

This case mouth denting is common on 300 BLK AR's. It really is no big deal, as they are usually not hurt enough to be resized.

I use a cut down piece of stick on bike tire patch and attach to the face of the brass deflector, where the brass is leaving a mark. It only takes a small piece to attached there to ease your worried mind.

Mine were blue in color, a black marker made it all but disappear, it worked just fine.

TR

TRshootem wrote:This case mouth denting is common on 300 BLK AR's. It really is no big deal, as they are usually not hurt enough to be resized.

I use a cut down piece of stick on bike tire patch and attach to the face of the brass deflector, where the brass is leaving a mark. It only takes a small piece to attached there to ease your worried mind.

Mine were blue in color, a black marker made it all but disappear, it worked just fine.

TR

Sticky backed Velcro works better and no need for a Sharpie.

TRshootem wrote:This case mouth denting is common on 300 BLK AR's. It really is no big deal, as they are usually not hurt enough to be resized.

I use a cut down piece of stick on bike tire patch and attach to the face of the brass deflector, where the brass is leaving a mark. It only takes a small piece to attached there to ease your worried mind.

Mine were blue in color, a black marker made it all but disappear, it worked just fine.

TR

Thank you TR, that's all I needed to know...

S/F