Jump to content
AR15Armory.com

New 18" American 30 Barrel


bj139
 Share

Recommended Posts

I just bought an 18" American 30 barrel. I bought some 30 Herrett Pacific dies and found the expander did not fit in the 6.8mm case.

So, I ran some cases into a 300 Blackout die to enlarge the neck being careful not to run the case in too far.

I then ran the cases into the 30 Herrett die just until I felt some shoulder resistance. The shoulder got a bit sharper and I stopped.

I seated a bullet into an empty case for testing. I forgot I have to trim to 1.620" and will do this next.

I wonder why the chamber was designed to be trimmed at all? Why not just size and load?

Link to comment
Share on other sites

  • Replies 68
  • Created
  • Last Reply

Top Posters In This Topic

I just bought an 18" American 30 barrel. I bought some 30 Herrett Pacific dies and found the expander did not fit in the 6.8mm case.

So, I ran some cases into a 300 Blackout die to enlarge the neck being careful not to run the case in too far.

I then ran the cases into the 30 Herrett die just until I felt some shoulder resistance. The shoulder got a bit sharper and I stopped.

I seated a bullet into an empty case for testing. I forgot I have to trim to 1.620" and will do this next.

I wonder why the chamber was designed to be trimmed at all? Why not just size and load?

 

Because if you tried to seat heavy bullets in the cases the ogive will be back in the case neck. Also based on where the bullets ride in the magazine this is the longest that can be used and still allow reliable feeding from a magazine due to the location of the ribs.

 

As to your 300 BLK the expander is the same size. You just have to lube the inside of the necks to expand. From 277 to 308 is nothing in the expansion world. I used 6X6.8 cases fired a dozen times to make mine. No issues at all and no neck splits. You just have to be strong and do it. I KNEW mine was going to crush yet after making severl hundred cases I have not lost one nor have the other two developers.

 

W spent months working out all the nuances on this one when we designed it. It outruns any other short 30 on the market and is right with the 30 RAR. It is 150 FPS faster than a 30-30 in an AR platform.

 

Greg

Link to comment
Share on other sites

I can see this site again. Thanks for your help GL.

I have been making dummy rounds of American 30.

I trimmed two cases to 1.610 and 1.615. I was trying for 1.620 but overtrimmed a bit.

With a receiver and BCG the cases would not extract so I guess they are a little too short and would not engage the extractor.

They fell out when I turned the barrel upside down. I seated a 110g Hornady Vmax to a COAL of 2.310 and they fit in a magazine.

They also now extracted from the barrel with the extractor so I guess the bullet is in the lands.

I don't know if I should try to fireform with a few grains of red dot and some wadding (no bullet) or should I load some 20% below max loads and just shoot at the range.

I think I did read where the shoulder will be blown forward to fit the chamber.

Anyway, I'm taking it slow.

Link to comment
Share on other sites

Trim length has nothing to do with extraction unless it's too long jammed into the throat with a bullet. Shoulder height is the issue. Size the shoulder a bit less on a couple of cases and try again.

 

 

There have been several reamer changes since Ritch and I developed this cartridge. Get couple cases to fit and blowthem out with Red D or Bullseye and corn meal toget some comparison cases. Then you can use the Sinclair bullet seating tool to keep out of trouble.

 

Greg

Link to comment
Share on other sites

I found that if I touch the shoulder any amount with the Herrett die the case is too deep in the chamber and the extractor does not get over the case rim.

 

It works if I just expand the neck with a Lee .308 depriming rod with expander inserted into my Lee universal decapping die.

 

Then, I just trim and the case fits in the chamber and the extractor snaps over the rim and can be ejected.

 

I close the bolt slowly as you mention in another thread to avoid hammering the shoulder back.

 

Next I will try fire forming with corn meal after the Superbowl since my neighbors should not notice because of the firecrackers people will set off.

 

If the Eagles win I should be able to do a lot of fireforming.bellylaf.gif

Link to comment
Share on other sites

I didn't get to fireform since our dog was nervous hearing the fireworks. If I touched one off in the basement he may have passed out.

I also thought it through and realized I did not want to be blowing corn meal all over the basement.

I think I might have some old 30 cal plinkers which I will load for fireforming. I will report when I do more.

Link to comment
Share on other sites

On other sites I can upload photos as long as they are small.

I set up a Flickr account but they wanted to scan my computer and upload all my photos to their site.

I am not ready to turn my computer over to a third party.

 

I just loaded 10 rounds as I said above. Three chambered and extracted fine and the bullet had no marks.

I seated them a lttle longer than a factory 55gr 223 round. They drop in with a thunk and fall out freely when inverted.

I will try to shoot them tomorrow at 50 yards.

I will post photos from an image hosting site if I can figure out how to limit them in their zeal to get more photos.

 

https://www.flickr.com/photos/141960851@N06/40122660141/in/datetaken/

https://www.flickr.com/photos/141960851@N06/39223269655/in/datetaken/

 

https://www.flickr.com/gp/141960851@N06/v1Uqef

https://www.flickr.com/gp/141960851@N06/tN0x15

 

Which of these can you see? The first 2 or last 2 or both?

Edited by bj139
Link to comment
Share on other sites

On other sites I can upload photos as long as they are small.

I set up a Flickr account but they wanted to scan my computer and upload all my photos to their site.

I am not ready to turn my computer over to a third party.

 

I just loaded 10 rounds as I said above. Three chambered and extracted fine and the bullet had no marks.

I seated them a lttle longer than a factory 55gr 223 round. They drop in with a thunk and fall out freely when inverted.

I will try to shoot them tomorrow at 50 yards.

I will post photos from an image hosting site if I can figure out how to limit them in their zeal to get more photos.

 

https://www.flickr.com/photos/141960851@N06/40122660141/in/datetaken/

https://www.flickr.com/photos/141960851@N06/39223269655/in/datetaken/

 

https://www.flickr.com/gp/141960851@N06/v1Uqef

https://www.flickr.com/gp/141960851@N06/tN0x15

 

Which of these can you see? The first 2 or last 2 or both?

 

I see neither

 

Greg

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...