Brass or chamber problem **new pics**

[christopher6968]

These are .50 DTC fire forming rounds (LC 03) fired from my bohica. besides the obvious splits what is going on with the ring towards the base of the case?

[Timberwolf]

If these are reloads thats from FL sizing.

[JeffM]

Looks like they may have been undersized. Brittle brass maybe too. I've had new factory loaded S&B 5.56 cases split down the side like the second from the left.

[christopher6968]

Thanks for the reply yes they are reloads. The ring is not apparent on the unfired rounds.

[StraightShooter]

If the ring is not apparent on the unfired rounds then I would definitely check the headspace in your rifle. If the rings at the base arent apparent in the unfired rounds then they cant be caused by the sizing die. It also seem that the cases are undersized and or brittle. Be careful.

[Timberwolf]

Thanks for the reply yes they are reloads. The ring is not apparent on the unfired rounds.

If they're not apparent on the reload before firing you're resizing way too far or you have an oversized chamber maybe or a combination of the two or . . . either way those are stretch marks - take a paper clip and check the inside of the unblown brass and feel for a depression at the ring. If you feel a rough spot or depression can the brass - blowouts are disturbing enough case seperations are a different story

[Pthfndr]

- blowouts are disturbing enough case seperations are a different story

Especially in a .50 cal of some sort!!!!

[brando]

Flush primers too? I recently went through a similar thing with my .408, having what I believe was a bad batch of brass that was too soft, resulting it too much stretching, back pressure and eventually a case head separation.

[mrkubota]

Hmmm,

This is the 3rd report I've received of buldging case walls near the casehead from an FAR-50. The other two were from Mk-2 guns. Is yours the same?

As Brando asked... I'd like to know of the primers were flattened out as well.
That would also point to a possible headspacing issue as well.

The initial load development for the BOHICA guns was done with a Mk-1 (thanks MustangO3) and we didn't get that kind of odd expansion. Certainly is beginning to look like the Mk-2 chambers are a little oversized near the casehead.

The first report came in from Draconianruler a few weeks ago with ammo made from LC-06 brass. No splits in that instance, and I sent him some additional ammo made from a variety of other headstamp fire-formed cases to rule out a brass problem.
He still got the odd buldging at the casehead with the fire-formed ammo.

The second report came in yesterday after a local shoot, noting the same buldging (no splits). That upper I'll have the chance to chamber cast on Friday, so that should tell the tale then.

If any other shooters have the Mk-2 DTC guns, please refrain from fire-forming the DTC ammo until we've had a chance to determine with certainty what the issue is.

If there are any other Mk-1 DTC shooters out there, what have your experiences been?

//Ben

[christopher6968]

thank you guy's for the input I'll get a pic of the primers up tomorrow.

Ben it is a mk 2

[ar15barrels]

If these are reloads thats from FL sizing.

He said they are forming loads.
The 50 DTC is made by shortening a 50 BMG case and pushing the shoulder back.
If the dies was setup right, there would not be a ring like that.
It's quite possible that these were formed short for the gun, or the gun has LONG headspace.

Remember that headspace GAUGES are absolute, but it's easily possible to taylor brass to correct for guns with long headspace.

[christopher6968]

primer pics added

[brando]

Those primers don't look too bad to me...hmm. Er, on second look they do look like they're filling out a bit. They're just not insanely flush like my .408's.

[50 Shooter]

Primers look good to me, when they flatten out in a .50, they flatten out! You can tell as the primer will be FLAT and flush with the back of the case to the point of where it looks like one solid piece.

[brando]

Here's the flat primers I was comparing them to...

http://www.box.net/shared/sbyjqp2ck0