Cases sticking at base

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sailhertoo

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Got a friend with two guns, 308 and 6br, and on both of them the cases are very hard to extract and leaving scratch marks on the base of the cases where they stuck.

What is going on here? Bad brass? I thought brass expanded upon fireing and then contracted to allow the case to slide out easy. This is with mild loads.

Thanks for any help you can give
 
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The chambers are too small for the loads he's running.

Caseheads DO NOT spring back, nor can they be "contained."

Options are to keep the loads lighter or open up the chamber.

al
 
sailhertoo said:
Got a friend with two guns, 306 and 6br, and on both of them the cases are very hard to extract and leaving scratch marks on the base of the cases where they stuck.

What is going on here? Bad brass? I thought brass expanded upon fireing and then contracted to allow the case to slide out easy. This is with mild loads.

Thanks for any help you can give
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Generally, when cases are sticking at the chamber base you have one of the following'

1) The F/L die is not the proper die for the chamber. In commercial chambers this can usually be solved by using "small base" dies. In benchrest chambers it means whoever matched the F/L die to the chamber screwed up, or;

2) the load is too hot for that particular combination of barrel, bullet, and temperature. Can be caused by simply using the wrong powder for that bullet, or using too much of the proper powder, etc.

Remember, the data in loading manuals is not the gospel. It is simply the results of that particular barrel, powder batch and such.

Most loading manuals published today have a pretty good safety factor, not so on many older manuals. STILL, back off a bit and work up. You probably will never find the hottest loads to be the most accurate. Which is more important, going fast, or hitting the aiming point??

Over time many things change, for example, consider in the #322 powder history of what country and who made it and when. #322 has been made in at least 3 different countries and by several different manufacturers. Same with many other "duplicated" powders on dealers shelves today.
 
If you had just said 6BR, the problem could be that it was chambered with one of the older pre-Lapua brass reamers. When Lapua brought out their brass, they decided to make it about .0015 bigger at the web than the older Remington and Norma. This caused the very problem you are referring too.

The '06, probably what the others said. It is a fact, that unless there is a mechanical problem, hard extraction and sticking is one of the signs of too hot a load for a given combination........jackie
 
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Does it do it with factory ammo?? That is the first thing to check.
 
I ment so say 308, not 306.

The reamer came from PT&G about a month ago. Its a new match reamer in his 6br. I don't know what reamer was used in his 308.
 
sailhertoo said:
I ment so say 308, not 306.

The reamer came from PT&G about a month ago. Its a new match reamer in his 6br. I don't know what reamer was used in his 308.
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So, it starting to sound like the same gunsmith did both guns??

Not trying to give you a short answer but take them back and let that smith diagnose the problem.

At this point I still feel it is a mismatch between the chamber and the sizing dies.
 
I chambered his 6br and Whidden(sp?) chambered his 308.

I'm wondering if I could have done something wrong in my chambering his 6br.

As far as his 308, I don't think Whidden would make any mistakes! I know he don't on the fireing line for sure!

Oh, he is using standard redding dies I believe, not a custom made die.
 
Nobody screwed up, except the guy who spec'd the reamer.

This is a very common problem.

al
 
Wes,

most custom reamers are undersized. It's in the nature of gun people to minimize tolerances. Kiff probably sells more "SAAMI Min" reamers than any other spec callout. Then there's a slew of "Minimum Palma" chambers out there in the 308, and a whole bunch of variations of the 6BR that are called "min" of some iteration.

Secondly there are a raft of reamers sized to fit factory FL sizers. These too are too small.

Generally people think that tighter is somehow better, more accurate.

Which is crap

Don't even get me started on "minimizing tolerances to promote better alignment".................

al
 
IMO reamers should be ordered using the actual numbers that will eventually show up on the reamer drawing. Shooters, and perhaps some gunsmiths tend to toss around terms like minimum SAAMI, and match, when in many cases, they could not tell you what actual dimensions are that are associated with them. Chambers need to reflect the size of brass, and if they are too small at the head problems will arise, no matter what die is used. Unless a custom die is planned, even if the chamber is large enough in relation to cases, a chamber that is overly large, when compared to a case that has been sized by the intended die, will result in excessive working of cases, and an undesirable looseness of fit. So, it is desirable that the dimensions of the chamber (reamer), brass, and FL die are coordinated, and that reamers be ordered with complete understanding of the dimensions. I should also mention that in my experience, the best way to determine the sized case dimensions that a die will produce, is to size a well work hardened case with that die, and measure it. This solves the problem of estimating spring back.
 
Boyd Allen said:
IMO reamers should be ordered using the actual numbers that will eventually show up on the reamer drawing. Shooters, and perhaps some gunsmiths tend to toss around terms like minimum SAAMI, and match, when in many cases, they could not tell you what actual dimensions are that are associated with them. Chambers need to reflect the size of brass, and if they are too small at the head problems will arise, no matter what die is used. Unless a custom die is planned, even if the chamber is large enough in relation to cases, a chamber that is overly large, when compared to a case that has been sized by the intended die, will result in excessive working of cases, and an undesirable looseness of fit. So, it is desirable that the dimensions of the chamber (reamer), brass, and FL die are coordinated, and that reamers be ordered with complete understanding of the dimensions. I should also mention that in my experience, the best way to determine the sized case dimensions that a die will produce, is to size a well work hardened case with that die, and measure it. This solves the problem of estimating spring back.
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So run a case through your die and send it to Kiff to make a reamer for it? Sounds like a good idea to me. As far as how tight to make the chamber reamer to the proof case, what would you tell Kiff?

Oh and Al, you crack me up! Thanks for all the good info.
 
Bob Kingsbury said:
Seems quite odd that two different guns, two different chambers, by two different people have the same problem
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Not to me.

My first 4 22BR, my first two 308, my first 4 6MMBR and my first 3 .243AI chambers and reamers were all too small. In fact it probably took me 15-18 chambers to learn my lesson. Most chambers are too small for extended high-pressure reloading. And by "high pressure" I'm not talking about brass-wrecking pressures. I just got bit again a couple years ago when I ordered my 300WSM reamer from the Redding die that Kiff makes the reamer for. Reloading to factory 300WSM velocities will cause this brass to tighten up within 3-5 reloads.

That reamer is now a resizer reamer :)

al
 
So Al, The solution to the problem is to get another reamer fitting the "hardened" case dimensions or is there any other way to make these two chambers and dies more compatable, i.e., not having to resize after each firing?
 
As I wrote in post #7 above, the problem is most likely the wrong sizing die for that chamber. Why recut the chamber when probably a small base die will fix the problem??
 
Jerry, Thanks I saw your reply and was hoping a regular redding body die would suffice but you are saying a small base die is necessary to solve this issue on a supposedly no neck turn 272 chamber because the maker of the reamer did not make it according to what he spec'd it out as? I have had three 6BR's and this is the first one that has acted this way after two firings of lightly turned necks in the new Lapua brass. Other rifles did not need resiizing after 8-10 firings. They were tighter chambers that it was necessary to turn the necks in.
 
wescummings said:
Jerry, Thanks I saw your reply and was hoping a regular redding body die would suffice but you are saying a small base die is necessary to solve this issue on a supposedly no neck turn 272 chamber because the maker of the reamer did not make it according to what he spec'd it out as? I have had three 6BR's and this is the first one that has acted this way after two firings of lightly turned necks in the new Lapua brass. Other rifles did not need resiizing after 8-10 firings. They were tighter chambers that it was necessary to turn the necks in.
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No, I'm saying that a small base die MAY be the easiest and a safe way to get the 6BR up and going. You can also send a few fired cases to the Harrell brothers and they will make a custom die for about $70.

Many things have happened to the BR (Remington RB, BR Norma, CBR, etc.) case. For one, there were at least two base diameters used for "standard" BR reamers. Another, the commercial die makers have never has a single "standard" to go by because of the previous mentioned problem, and, since the BR never really "went commercial bigtime", their problems with chamber dimensions didn't get properly wrung out.

Try the small base or Harrell die solution for the BR. Either way it will cost you less than $100 and give a safe solution. Just getting another reamer reground will cost much more than $100. Not to mention remachining the camber.

As to the 308, just get a small base die. Many semi-auto's chambered over the years in that cartridge work better with the small base die and this is considered a common solution.
 
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Jerry,
Thanks again for the help. I will try the small based die and see if that solves the problem.
 
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