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Hersh
11-06-21, 15:14
Guys a problem recently came up and I could use some help.

My precision build has a Compass Lake 18" Krieger barrel, 1:7.7 twist with their CLE chamber. So far it likes the Frontier 75 grain BTHP and the barrel has close to 1000 rounds total. At a two day class last weekend a problem came up repeatedly ... when trying to unload and show clear, the live round would not extract unless you mortared the rifle. After a good chamber cleaning on the first night, the problem continued the second day. Normally I use 10 round magazines and shoot until bolt lock so I can't say if this has been the case all along, or if it's unique to this lot which was bought a couple of years ago.

Later in the week I talked with Paul at CLE and he said there might be a headspace issue with this lot of Frontier and that shooting the ammo wouldn't hurt the barrel.

I'm still trying to get my mind around the concept of "headspace", does that mean that the chamber is too short for this round? Based on what I've read the CLE chamber has very little free bore and it sounds like the ogive is getting into the lands so doesn't that create an excess pressure risk? I reload pistol ammo, but am out of my wheelhouse on rifle rounds.


None of my brass from the class was saved so I'll need to shoot a few more and check for pressure signs. Anything else I should consider other that finding different ammo?

Thanks for any help.

DG23
11-06-21, 16:24
Later in the week I talked with Paul at CLE and he said there might be a headspace issue with this lot and that shooting the ammo wouldn't hurt the barrel.



Those guys would not have sent you the barrel if it was not right. They 'measured stuff' before it was sent out the door...

He was not talking about an issue with your barrel or chamber.

Hersh
11-06-21, 17:09
Those guys would not have sent you the barrel if it was not right. They 'measured stuff' before it was sent out the door...

He was not talking about an issue with your barrel or chamber.

I understood that and wasn't suggesting there was a problem with the barrel. Edited original post for clarity.

georgeib
11-06-21, 17:51
The Frontier ammo I had a couple years ago had noticeably rougher finished brass than what I was used to. Don't know if the stuff you have is like that, but unpolished brass plus a tight chamber might be the explanation.

ggammell
11-06-21, 18:40
The Frontier ammo I had a couple years ago had noticeably rougher finished brass than what I was used to. Don't know if the stuff you have is like that, but unpolished brass plus a tight chamber might be the explanation.

75gr Frontier just has problems. It’s the only ammo that’s blown a primer in my gun. I’ve seen several other complaints on forums, etc about it as well.

georgeib
11-06-21, 18:41
75gr Frontier just has problems. It’s the only ammo that’s blown a primer in my gun. I’ve seen several other complaints on forums, etc about it as well.Yup, I've read the same. Just figured, because people seem to be talking about it, that they've improved. Maybe not though.

Hersh
11-07-21, 00:35
75gr Frontier just has problems. It’s the only ammo that’s blown a primer in my gun. I’ve seen several other complaints on forums, etc about it as well.

Yeah after more digging, I'm seeing the same things.

DG23
11-07-21, 08:49
The Frontier ammo I had a couple years ago had noticeably rougher finished brass than what I was used to. Don't know if the stuff you have is like that, but unpolished brass plus a tight chamber might be the explanation.

His base diameter is the same as what should be in a 5.56 chamber. (the part of the chamber that grips the case when the round is fired and then releases after the pressure drops)

https://i.imgur.com/Cx7FqTX.jpg

In my .223 match chambers that area is slightly smaller / tighter but smooth. (his chamber is going to be smooth there - was not cut by the people at PSA) Proper pressure ammo does not 'stick' there regardless of if the brass is highly polished or not. Improper pressure ammo fired in the smaller 'match' type .223 chambers stick at the case mouth (and will sometimes leave that case mouth behind after extracting the rest of the case from the chamber)

Would not personally shoot that ammo in any gun I cared about. If someone gave me some for FREE - It would be pulled down and reloaded correctly. Powder would be dumped and cases resized / checked for length before bullet, case and primer were used with a known and proper powder charge.

georgeib
11-07-21, 09:05
His base diameter is the same as what should be in a 5.56 chamber. (the part of the chamber that grips the case when the round is fired and then releases after the pressure drops)

https://i.imgur.com/Cx7FqTX.jpg

In my .223 match chambers that area is slightly smaller / tighter but smooth. (his chamber is going to be smooth there - was not cut by the people at PSA) Proper pressure ammo does not 'stick' there regardless of if the brass is highly polished or not. Improper pressure ammo fired in the smaller 'match' type .223 chambers stick at the case mouth (and will sometimes leave that case mouth behind after extracting the rest of the case from the chamber)

Would not personally shoot that ammo in any gun I cared about. If someone gave me some for FREE - It would be pulled down and reloaded correctly. Powder would be dumped and cases resized / checked for length before bullet, case and primer were used with a known and proper powder charge.That's good to know. I was just speculating.