What is rough chamber?

24 April 2001, 16:57

<Kari>

Well, I can tell you about one! In my vintage 7 x 54-rifle there certainly was " a rough chamber". In year 1946 someone missed quality control in Valtion Kivï¿½ï¿½ritehdas (VKT), Jyvï¿½skylï¿½, Finland, later Valmet.

The chamber was rough, you could see it with your bare eye. I polished it with an unsized case, 800-grit polishing media and a power drill. Polishing, cleaning, test-firing - being very careful! What you take out - it never comes back. Now it is good, does not leave marks to cases.

I have seen rough chambers elsewhere, too. In couple of cheap revolvers, shotguns, I remember.

24 April 2001, 18:05

Bill Leeper

The gunsmith could also been talking about "roughing" the the chamber. This refers to the means of removing the bulk of the material prior to finish reaming. This is done either with a drill or a special "roughing" reamer or in some cases by boring depending on the preference of the gun smith. Regards, Bill.

24 April 2001, 19:01

Stefan

There is a point of having the chamber a little bit "ruff". The cases "grip" the chamber walls a bit better when the surface isnï¿½t shiny like a mirror. I useally give the finished chamber a few light passings with 320 grit paper after the chambering is done.

Stefan.

24 April 2001, 22:05

<Mats>

quote:
Originally posted by Stefan:
The cases "grip" the chamber walls a bit better when the surface isnï¿½t shiny like a mirror.

Stefan,

I'm not going to argue about the necessity of friction between case and chamber, or the strength of the brass in the web area, but - given that you have zero headspace, as most of us strive for - what difference would the chamber finish have? The base of the case is planted firmly against the bolt anyway - there's nothing to brake the load put on the lugs but then again, neither is there an impact from accellerated brass as with a headspace situation.

-- Mats

24 April 2001, 22:34

<AKI>

Gentlemen. I discussed this topic with my riflesmith, Jan Stenroos, some weeks ago. The main benefit is that it prohibits brass flow in cases with slow necks (usually 30ï¿½ is considered about safe against this phenomenon). He said that it works for cartridges like the 300H&H but he only makes them for customers who understand what itï¿½s all about because the rough chambers donï¿½t look good and cast a shadow ower the smithï¿½s competence in the eyes of people unaware of the benefits. "A few turns with 80 grit...".

Dear sweedes, nice to beat you to thisone!

AKI

24 April 2001, 23:18

<Don G>

He probably means "cutting to just under nominal dimensions" to save wear and tear on his finishing reamer. They sometimes do this with an old reamer.

25 April 2001, 04:35

Stefan

I canï¿½t say this or that is false or thru about ruff vs. shiny chambers, I have way to little experience in this area. I have a friend that have a lot more experience with chambering barrels than me and I got this tip from him.

Aki!

I donï¿½t know how much you have heard about Jan Stenroos as a gunsmith. I suppose the other guys at ï¿½land have explained the level of his work if you donï¿½t have figured that out by your self by now He is absolutely TOP CLASS!! I would say he would stand up to the best guys in US in the precision jobs, no doubt about it.

Stefan.

25 April 2001, 20:27

<Mats>

quote:
Originally posted by AKI:
The main benefit is that it prohibits brass flow in cases with slow necks (usually 30ï¿½ is considered about safe against this phenomenon).

AKI min vï¿½n,

A good point, I'd definitely "buy" that. As Stefan has pointed out, Janne Stenroos is a really experienced and skilled gunsmith, I've been very impressed by his work. I hope I have the cash to let him build me a couple of rifles sometime... I don't think I've seen any of the larger US BR smith's work, but Janne's work is excellent and more.

BTW: Any of the Swedish, ï¿½landian or Finnish members know of a decent LV or HV rifle for sale? Preferrably a PPC, but I ain't that picky. I'll get into a bunch of money this fall and want to get some more stuff. Moreover, I'm moving to a bigger flat so that I can get a big enough room for my loading equipment - we have the WBRC over here in 2003 and I'd love to get into competetive form so that Stefan and the guys could pick me out for the Swedish team...

-- Mats

26 April 2001, 09:43

<AKI>

Mats, kï¿½re vï¿½n. As I did it myself past winter, I recommend that you build a _new_ BR rifle. I bought a Shilen barrel and a Jalonen action. According to Janne Stenroos they are second to none (the new triggers are superb) and he has seen them all, the Stolles, Nesica, Geskes, Harts, Svensk Mauser... They are as good or better but cost less than half of the american actions or 3400 Finnish mark or about 5200 Swedish kronor (~500US$). I made the stock myself by gluing veneer together and shaping it with hand tools. Itï¿½s fun (except the polishing part...), educative, and first and foremost almost free. And, make it a BR as I did, not a PPC. I KNOW that most matches are won by PPC, but that is simple stocasticity and BR is fundamentally stocastic: If 99 shooters out of 100 use PPC they will win 983-997 matches out of 1000. Furthermore the wildbrain using anything different is no mainstreamer and is perhaps not as focused on winning, but also find some pleasure in beeing different, experiment or whatever, thus reducing the probability of a random win further. I made mine a 6mm BR, and I will kick some butt and stir some dust in the brains of the old stagnant PPC gang.

Why not get a Jalonen action and buy a Shilen of the local dealer here (his prices on these barrels are very humane concidering the level of the US$). Iï¿½m sure Janne will make something that will shoot better than the shooter (not that you wouldnï¿½t be a #1 shooter, but rifles capable of less than 3mm 5 shotters can shoot 8mm if the bigguy behind it wont do his part). Ask Stefan how his stockmanufacturing progresses, perhaps he could...

Looking forward to see you some day on some range! AKI

27 April 2001, 07:03

<Mats>

quote:
Originally posted by AKI:
...I recommend that you build a _new_ BR rifle.

Yeah, what the heck... The Jalonen actions are pretty nice, I just wish they were made for Remington triggers so that you could fit a Jewell to them - can't see that a better trigger could exist on this planet.

I ought to get on the phone to Torsten ï¿½strï¿½m and see what we could cook together...

Lessee... First goal: To beat Stefan in three straight matches, second goal: To beat an old man by the name of Boyer or something...

-- Mats

27 April 2001, 19:18

<AKI>

How DEAR you mention "Remington" in this context??? FWIW, in Jannes opinion the new Jalonen trigger is at least as good as any Jewell, so if you turn your eyes to the east you will se one as good or better. This should NOT be a problem.

To beat Stefan on the other hand, oh MAN... YOU got BIG problems

I bought a Jalonen JJ-92A, the aluminium action that weighs only 0.9kg, not necessary for HV, but some day LV might be interesting.

Good luck!

AKI

27 April 2001, 20:53

<Mats>

quote:
Originally posted by AKI:
To beat Stefan on the other hand, oh MAN... YOU got BIG problems

He he, I've had this secret goal since I started BR-ing, Stefan had and still has the club record at Sï¿½var (or is it Matti who has it? I might be wrong...) where we both shoot and he generally seemed like the guy to beat. In '99 I thought I reached my goal in Swedish Hunter class, it was the last local match of the season and I had a few mm's over him as we entered the last relay. My first three were tighter than a gnat's behind, number four stepped out but it was still a respectable group and smaller than Stefan's first four - around 22 mm as I recall. I waited for my condition to return, checked everything and pulled the "loud lever". I knew as I had let go that the group was perfect, everything felt just right. I had won and Stefan was second. I turned to him and smiled, he looked at my target through his scope and looked a little bewildered afterwards. I smiled a bit more and Stefan kinda half-laughed at me. Something was wrong... I re-aligned my rig and had a look at my supposed to be 22 mm group. Yup, looked just like the first four - but, wait a minute: What the Hell was that thing that looked like a perfectly round, stationary fly w-a-a-a-a-a-y to the right of the group? Could it be - nah, no way. But...DAMN!!!

That last shot was where my Redfield lost contact with reality. The damn thing developed about two MOA side-to-side slop... If I remember correctly, my group was 59 mm and my agg grew at the same rate as Oprah Winfrey at a Burger King.

Well, there's always next year...

-- Mats

09 May 2001, 07:52

<Kari>

Aki

You said you had a self-made veneer stock. What method did you use? I mean how you could accomplish and maintain the enormous pressure needed? I once tried with screw-on-gluing-presses but failed...what kind of laminate and glued you used? I'm also interested in your surface finish.

You see, I once rebuild a Sako 30-06 rifle. It wears now a laminate stock, but it's a long story...