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244-40x
10-27-2009, 08:40 AM
mornin guys, i got a model 70(post 64) chambered in 25-06. after fired i was looking at the brass and noticed that the chamber marking near the head of the brass is bulged out on one side and flat on the other. it's obvious something isn't lining up correctly, i'm guessing either crooked barrel threads or lug problems. any suggestions?

Dave Tooley
10-27-2009, 01:13 PM
If it's the sidewall in front of the case head it's showing you one of several things or a combination of things.
1. If the case is not forced off to one side by the bolt, it's possibly the thin side of the brass yielding first.
2. If it is forced off to one side all the cases will show the bulge at the same location, IE 1 oclock, 3 oclock etc. Possible but not likely.
3. All brass shows this to some degree or another. Mostly a function of chamber diameter vs brass diameter. Brass does not expand uniformily.

Dave

NesikaChad
10-27-2009, 01:33 PM
I'd venture to guess that the reamer went a bit cockeyed and your chamber isn't quite as round as a guy hopes for.

Rustystud
10-27-2009, 02:01 PM
If the chamber was cut with a reamer that had no pilot or a loose fit pilot there is a possibility the reamer may have yawled during the ream process. I have customers bring in barrels done by other smiths with chambers "WOLLERED OUT" in the web area. Some with localized "WOLLER and others with concentric WOLLER". This can be made worse with a floating reamer holder.

Nat Lambeth

Butch Lambert
10-27-2009, 03:21 PM
How can you ream an out of round chamber? I can see larger at the base, but not eggshaped. I'm not smart enough to do that even trying.
Butch

J. Pendergraft
10-27-2009, 03:31 PM
Likely nothing wrong with the gun (what D. Tooley said). How does it shoot? If OK then shoot it and don't worry about what the brass looks like.

Larry Willis
10-27-2009, 03:53 PM
244-40x ......

It would be interesting to see a crisp clear picture of your deformed cases.

- Innovative

Big Al
10-27-2009, 06:30 PM
How can you ream an out of round chamber? I can see larger at the base, but not eggshaped. I'm not smart enough to do that even trying.
Butch

It is fundamental to a machinist understanding that reamer want to cut oversize, it's the nature of the tool. Also if the reamer is held vertical or horizontal makes a big difference. Just like a spiral flute drill bit.

Dans40X
10-27-2009, 07:06 PM
There's more than one Win70 chamber out there that is EGG shaped from the factory.
The controlled round feed chambers were the worst.
Neck sizing is/was imposable.

Butch Lambert
10-27-2009, 08:51 PM
Big Al,
I understand that, but how can you cut an egg shaped chamber? Do you run a reamer in and out too fast that it only hits one side of the chamber? Think about it- if the reamer is high, low, right, and left it will only make the reamed hole larger.
Butch

Rewinder
10-27-2009, 10:08 PM
Maybe the chamber was cut for .470 dia brass instead of the .466 dia. Win,Rem brass that is sold today. Try some LaPua brass which is .469 dia. and I bet the swelling goes away. Randy

Bnhpr
10-27-2009, 11:42 PM
How can you ream an out of round chamber? I can see larger at the base, but not eggshaped. I'm not smart enough to do that even trying.
Butch

Butch,

I had a Ruger 77 22-250 in my shop that had an egg shaped chamber. I sent it to Ruger and they recommended destruction of the rifle since it had been overpressurized.

I gave it to Bill Morrison to look at and he called BS. It was clearly machined egg shaped.

We bored it, set it back and it shoots fine.

Ben

alinwa
10-28-2009, 02:35 AM
mornin guys, i got a model 70(post 64) chambered in 25-06. after fired i was looking at the brass and noticed that the chamber marking near the head of the brass is bulged out on one side and flat on the other. it's obvious something isn't lining up correctly, i'm guessing either crooked barrel threads or lug problems. any suggestions?


This post in no way refers to any of the fine posts already up. This is ME to YOU.

IMO your chamber is fine. Factory rifles do this often.

Not only that, I chamber full-blown BR guns with oversized chambers so that they do this.

Here are a few of my thoughts. Take them for what they're worth.

---Brass will always blow out on the thinner/weaker side regardless of orientation.

---I use this feature, I consider the brass cases which blow out evenly to be my "best" cases.

---I say, fuh'GEDDAboudit...... it's ain't a thing. Just find a die that fits, or polish one out, and move forward. There is no downside.

I DID have what I thought was an egg-shaped chamber once but this is extremely rare.... EXTREMELY rare. In my case I figured that the barrel had been mis-manufactured and was a lot harder on one side and that the gunsmith had used a floating reamer holder. I can't see any other way that the egging could occur. AND..... i'm still so skeptical of my assessment that I kick myself for having worn out the barrel and chucked it. Stupid of me. If I had it now I'd spend some time measuring the chamber up, probably to find that my assessment was wrong! :o


Now, that said, I've heard rumors that some factory rifles have the chamber all or partially HAMMER FORGED with the mfgr of the barrel itself, that the chamber is built into the barrel mandrel. (most factory barrels are hammer forged cold) and IF THIS IS TRUE then it's entirely possible that there are a bunch of egged factory chambers.

Again though...... it is my opinion that you've just got a typical factory chamber, probably cut with a NEWER reamer than others. And that it's "fine" as far as factory chambers can be fine.

al

Butch Lambert
10-28-2009, 07:30 AM
I don't recall saying that there are not any eggshaped chambers. How are they made? I am not smart enough to know how unless it is hammer forged.
Butch

NesikaChad
10-28-2009, 09:17 AM
Understand it kills me to admit this. I have a 22-250 built on a Nesika that started as a bet between myself and one of the employees there.

I built this gun in a hurry. I mean a HURRY. It was started at 3 in the afternoon and I fired the first group at 10pm that night.

7 hours.

While chambering this gun something went a bit askew and the indicator showed a .0017"-.002" runout in the chamber. My threads and the unturned portion up by shoulder however were almost nothing. A couple tenths at the most. Well, I have brass that looks a little funny when it comes out. It is almost identical to what the OP describes. I don't know how/why the reamer went a little cockeyed, but it did. FWIW this is the hardest holding gun I own. It's shot more than a few 5 shot groups under .100"

So, as someone said earlier. Shoot it. If it's a hammer just keep shooting it and ignore the goiter growing out of your case webs.

Cheers,

C

Bob Kingsbury
10-28-2009, 10:51 AM
I agree with Dave Tooley, Its common in nearly all factory chambers.
to one degree or another, and always relative to clearance and brass.
Out of round chambers do occur and most that I have seen have been
re-chambered. I cannot explain how or why, but guess that the true
bore center was not found prior to re cutting. Certain barrel setups
allowing axial misalighnment, bore run out which is to deep to indicate and
done in lathes where the alignment at the muzzle cannot be verified
except visually come to mind.

Bob Kingsbury
10-28-2009, 10:59 AM
An old article in Precision shooting magazine by T.J. Jackson
said he was unable to find an accuracy difference with
cases that were expanded off center. His testing was with
a 6 br and I believe R-P brass. worth reading, as T.J.
was a very capable experimentor

alinwa
10-28-2009, 01:36 PM
While chambering this gun something went a bit askew and the indicator showed a .0017"-.002" runout in the chamber. My threads and the unturned portion up by shoulder however were almost nothing. A couple tenths at the most. Well, I have brass that looks a little funny when it comes out. It is almost identical to what the OP describes.

C



If a chamber is egged, it doesn't look funny, it means that you must index your brass or it'll jam in the chamber....... you can only reinsert your fired rounds one way, like a key in a lock. Back in the 80's I was all about Wilson dies and neck-size only reloading. I had a chamber that tended to jam, I marked my caseheads with a Sharpie....vertical line. I think it was egged, at the time I said it was, but I may have been just firing it too hot.... :o ..... and this being a 22BR and a fat one, the Wilson die was sizing it a little..... I've wondered lately, I never took a chamber cast...... I was using the dies with a hammer and remember that these tapped out hard......

I'll never know now.

al

244-40x
10-29-2009, 10:39 AM
thanks for everyones reply. the best i can get this gun to shoot is about inch and a half, i've been hunting for a load for over a year now, just can't match one up. this is why i was questioning the chamber maybe. it is just a hunting rifle and if thats the best it can do so be it. i just keep reading about some of the factory 70's being lacking in the accuracy dept due to poor assembly. i thought this may be one of them. thaks again

alinwa
10-29-2009, 01:37 PM
thanks for everyones reply. the best i can get this gun to shoot is about inch and a half, i've been hunting for a load for over a year now, just can't match one up. this is why i was questioning the chamber maybe. it is just a hunting rifle and if thats the best it can do so be it. i just keep reading about some of the factory 70's being lacking in the accuracy dept due to poor assembly. i thought this may be one of them. thaks again

some thoughts......

--Inch and a half groups seems perfectly normal for the model 70. Welcome to reality, the difference between internet groups and real-world. That said, some of the newer Sav/Rem rifles are honestly shooting well under an inch right now. This is huge....

--An egg shaped or oversized chamber wouldn't have any measurable effect on accuracy.

--Beware of keyboard shooters claiming they bought a "Monday rifle" because "it was assembled well" VS a "Friday rifle which shoots like @#$%," because there is no such thing. YES some factory rifles do come out straighter and therefore more accurate, pure luck..... But the Win70 has never been known for accuracy. Generally speaking, push-feed M70's shoot better than Mauser style ones like pre-64 and Classic.

opinionsby


al

Vibe
10-29-2009, 01:51 PM
How can you ream an out of round chamber? I can see larger at the base, but not eggshaped. I'm not smart enough to do that even trying.
Butch
Strange production method involving a spinning reamer and a stationary (almost) barrel - Otherwise I would agree with you in that with the work (barrel) spinning the chamber might be off center or oversize but basically concentric.

Larry Willis
10-29-2009, 03:58 PM
Vibe .......

Due to the cost effective methods of machining production rifles, chambers can (and sometimes are) out of round, oversized and not concentric with the bore. Sometimes it's so bad enough to see the chamber mis-alignment with a bore scope. The technique required to make an accurate rifle barrel requires much more time consuming machining techniques.

- Innovative