Dented case necks ...

[Flatlander]

I have been shooting a 16" Noveske 300 AAC. 19-20 gr H110 and a 110 gr bullet. Runs like a top but my case necks are consistently dented on one side. I think this is an action spring or buffer issue? I am running a standard carbine spring and buffer. Please advise.

[Stickman]

This happens on all of my various 300BLK uppers as well, regardless of what buffer I use.

[Flatlander]

Good - then I won't change anything ... this 300 upper has been a great experience so far, unlike my last one.

I just need to find a quantity of plinker bullets.

[UWone77]

Good - then I won't change anything ... this 300 upper has been a great experience so far, unlike my last one.

I just need to find a quantity of plinker bullets.

Let us know when you find some. I have a few thousand rounds stocked, but haven't shot any 300 until the pipeline opens up.

[Stickman]

Good - then I won't change anything ... this 300 upper has been a great experience so far, unlike my last one.

I just need to find a quantity of plinker bullets.


What were you using before, and what is your current setup?

[Flatlander]

I Am currently shooting a 16" Noveske carbine gas with a 13.5" NSR and a Leupold 1.25-4. My first one was a CMMG that was problematic but bolt related. We have been hunting hogs but not much luck just yet. Hand loads of a 110 gr Hornady V-max and 110 gr Barnes. Starting to wonder if a 30 carbine bullet would feed, seems to be only lightweight 30 cal available.

[freebug]

This is completely normal. The 300blk case when ejected does a 180 can causes it to hit the deflector on the neck. The 5.5.6 being longer does not do enough rotation and shouldn't have this happen.

[Ride4frnt]

Yep, my 16" noveske pistol length does it too. I'm running a Wolff XP spring and spikes t2 buffer.

[xxspudxx]

New to 300 blk and this answered all my questions.

8.5" with a KX3. JP Captured Spring.

[GaSwamper]

I Am currently shooting a 16" Noveske carbine gas with a 13.5" NSR and a Leupold 1.25-4. My first one was a CMMG that was problematic but bolt related. We have been hunting hogs but not much luck just yet. Hand loads of a 110 gr Hornady V-max and 110 gr Barnes. Starting to wonder if a 30 carbine bullet would feed, seems to be only lightweight 30 cal available.

What kinda performance are you getting out of the 110gr. Have you tried it on any hogs yet or no luck so far?

[kwiksnake]

Same here....all dented. I was having an issue with crushed cases but I was running a NiB bcg. After I put a regular one in there, no more crushed cases

[bzdog]

This is completely normal. The 300blk case when ejected does a 180 can causes it to hit the deflector on the neck. The 5.5.6 being longer does not do enough rotation and shouldn't have this happen.

this is my understanding and experience as well,

-john

[yamma]

I've heard folks say putting some felt or a rubber pad on your brass deflector will help but haven't verified it yet as I haven't shot my blackout upper since. I can verify that it's from the rounds hitting it though as Ive watched it happen. The case flips much quicker than the 5.56 cases and what would be a ding on them is a dented mouth on the .300.

[GaSwamper]

It must be just the right length, my .277 WLV cases are just like the BLK basically just a tad longer and they don't ding at all from what I can tell.

[WHSmithIV]

Just out of curiosity for those of with the .300 blackouts, wouldn't those dented cases be a problem to reload? I want to build one in .300 blackout as a pistol but I'd sure hate to not be able to reload the cases.

[BC98]

Just out of curiosity for those of with the .300 blackouts, wouldn't those dented cases be a problem to reload? I want to build one in .300 blackout as a pistol but I'd sure hate to not be able to reload the cases.

No, the case mouth is resized back to spec.

[Ride4frnt]

Just out of curiosity for those of with the .300 blackouts, wouldn't those dented cases be a problem to reload? I want to build one in .300 blackout as a pistol but I'd sure hate to not be able to reload the cases.

These aren't huge dents. Here's one of the casings from my .300blk, the flat spot on the bottom right of the case mouth is the type of dent in question

http://i1048.photobucket.com/albums/s374/blue94dc4/Misc/CD586A31-5435-446C-AAD1-095D29EF769D_zpscjq83zy0.jpg

[WHSmithIV]

Interesting. I wonder if it was ejected with a little less force if that would prevent it from flipping all the way around to hit the deflector.

[velocity2006]

These aren't huge dents. Here's one of the casings from my .300blk, the flat spot on the bottom right of the case mouth is the type of dent in question

http://i1048.photobucket.com/albums/s374/blue94dc4/Misc/CD586A31-5435-446C-AAD1-095D29EF769D_zpscjq83zy0.jpg

That will come right out after being run through a sizing die and looks completely normal as far as I can tell. Probably caused by hitting the shell deflector as it is a flat indentation on the case mouth.

Probably likely because of the shorter case length on the 300BLK casing. You're using the same upper design for a shorter shell casing, so where a 5.56 would bounce of somewhere on the shoulder or just before it, the 300BLK hits on the mouth as its a shorter case.

[WHSmithIV]

That will come right out after being run through a sizing die and looks completely normal as far as I can tell. Probably caused by hitting the shell deflector as it is a flat indentation on the case mouth.

Probably likely because of the shorter case length on the 300BLK casing. You're using the same upper design for a shorter shell casing, so where a 5.56 would bounce of somewhere on the shoulder or just before it, the 300BLK hits on the mouth as its a shorter case.

That cause I understood from reading the earlier posts. Thanks for posting the picture because it's obvious the resizing die word sort it out. i wonder what modification could be done to prevent it.

[ShiskaBob]

I would assume that fiddling with the ejector/ejector spring could reduce how much the 300aac case rotates, so that the case could rotate more similarly to the 5.56, but that would surely lead to overly weak extraction in fouled rifles. The easy solution to the dents is probably just to glue a piece of rubber onto the brass deflector. Or use a slickside upper.
I am glad to discover I'm not the only one with the issue. I had figure it was just because I was using a billet Seekins upper with a unique profile on the brass deflector.

[WHSmithIV]

That's what I was thinking - fiddle with the ejector spring in the bolt. I'm not sure anyone would want to glue anything to their upper receiver though possibly just a dab of black silicone could be laid on since it would come off easy enough. If they are only as severe as that picture though then it shouldn't be an issue for reloading and that's what I had started thinking about.

[Dstrbdmedic167]

Just out of curiosity for those of with the .300 blackouts, wouldn't those dented cases be a problem to reload? I want to build one in .300 blackout as a pistol but I'd sure hate to not be able to reload the cases.

I'm in the process of a 300blk build but reload several other calibers.. I've never had a problem resizing the dented case mouths.. maybe a tad more resistance but not enough to cause any major issues.

[tcoz]

It isn't a problem. Don't overthink it.

[Kopis]

This is completely normal. The 300blk case when ejected does a 180 can causes it to hit the deflector on the neck. The 5.5.6 being longer does not do enough rotation and shouldn't have this happen.

yes this is why. they all do it.