.300BLK Issue...

[DocSavage]

Like a Godian Knot, this is kicking my butt!

Background...

10.2" Noveske barrel from them with no modifications aside from the standard M4 feed ramps.

Reloading 300BLK on my Hornady LNL AP Press with all in spec stuff from Hornady...

Recipe...

12.0 grains AA5744
190 grain SMK
.223 recut to 1.390
COAL is 2.185

Result...

When fed from magazine, BCG will not go all the way into battery. When fed singly, we go into battery, but will not manually cycle to eject - without firing, needing rather to mortar the rifle.

The image below are the marks on my round...
Measuring at the marks left give me .3705.

I've measured Hornady's .300 WHISPER rounds and they are .2990 at the same place, and I have no feed issues with them at all.

Solution...

So here's my ?... Do I keep looking for different bullets? I have some AMax's, but damn they're a tad $$$ for range plinking... Should I have the throat reamed? This barrel was pricey from Noveske, so do I send it back?

ObiWan you're my only hope! What would you do?

Cheers, Ian

 

[IndispensableDestiny]

Well, first of all the SAAMI maximum shell length is 1.368. The minimum chamber is 1.378. I cut my .223 brass to 1.390 and then trim it to 1.365. I've had no feed issues with a Noveske upper receiver and Noveske 14.5 in barrel.

Get a headspace gauge for .300 BLK. Also, try to make a chamber cast of your barrel.

 

[HarCo2ANewb]

This. Looking at your brass, I can tell the neck is too tall.

 

[DocSavage]

ID,

Thanks for the reply! Best thing about this community is that many folks "have been there" before...

Here's a shot from Hornady's 9th...


So you're saying to go smaller than what my manual says? I understand that the value given is MAX case trim length...

Just measured case on a factory round @ 1.3610. Mine are coming in at a solid 1.38...

So bullet shape and ogive value is NOT my issue, rather it's my case length?

Who makes the best book for 300?

Thanks again for the quick reply...

Cheers,

Ian

 

[FlatsFlite]

nevermind

 

[HarCo2ANewb]

The hornady 9th has a correction page for their .300aac info

From another thread:

http://www.hornady.com/assets/files/9thEdErrata.pdf

Also http://www.300blktalk.com/forum

 

[DocSavage]

The hornady 9th has a correction page for their .300aac info From another thread: Also http://www.300blktalk.com/forum

Wow...

I'm waaaaay off!

Thanks everyone!

Ian

 

[HarCo2ANewb]

Wow...

I'm waaaaay off!

Thanks everyone!

Ian

No problem, I had forgotten about the error until you posted the pic of your edition, let us know how those loads turn out, 190 isn't as common of a weight as say a 220/125/150 and I am sure your data will be appreciated.

 

[JailHouseLiar]

Never Mind

 

[tomgreco]

Awesome thread! I'm just getting into reloading 300 BLK.

 

[DocSavage]

Called Little Crow and they explained how easy it is to change the case OAL...

What nice folks!

Ian

 

[lax]

Sierra info
http://sierrabullets.files.wordpress.com/2013/07/300-aac-blackout.pdf
Nosler info
https://travis-furry.squarespace.com/300-aac-blackout

 

[DocSavage]

Ok..

Changed the case length on my trimmer and it seems to be functioning well... I just trimmed 200 pieces on my band saw, tumbled em up, and resized them.

I used Hornady's UNIQUE wax, and like it way better than the spray stuff.

Trimmed all of them up to 1.368 - 1.36 and they all seem to be feeding well. I'm using 208 gn AMax on top of 10.8 gn of AA5744.

Working on my sub loads and this seems very sweet into my test tube...

Headed to DSC this afternoon with my boys...anyone else?

Cheers,

Doc