Differing Chambers

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hitchphil
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Differing Chambers

#1 Post by hitchphil »

So after collecting ~900 empty RWS 308 cases, me thinks time to reload the lot 300 for me, 300 for son & 300 for Deadly Daughter. Clean, de-prime & measure lengths all OK.

Hm thinks- All were shot out of 2 guns nominally separate so lets check they fit unsized/ fireformed? - all but 50 fit the RPA Quadlock = :good:

The 50 wont fit, Swing, nor the Barnard, or the clubs Paramount nor the P14 = OK, resize, check length = OK & they all fit everything = :good:

Then those that cleared the RPA Quad - do they work in other chambers?

Barnard = No?
Swing = 90% No?
P14 = no?
Club Paramount = yes -eh?

so resize 600 to fit Swing & Barnard & leave 300 for my RPA as is. Job bone. start priming.

Are RPA chambers larger than other makes then?
Quality control of Scottish Ethanol. & RDX/HMX

& my fav chemical is :-) 1,3,7-trimethylxanthine.......... used to kill frogs.... but widely consumed & in vast quantities by the French? Eh?
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20series
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Re: Differing Chambers

#2 Post by 20series »

if you full length size the cases they should fit any of the chambers then keep them seperate afterwards

Alan
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ovenpaa
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Re: Differing Chambers

#3 Post by ovenpaa »

Hmm... not always. There are some .308 chamber reamers that are to SAAMI spec but at the rock bottom limits and even below so a gauge will just fit but only in a spotlessly clean chamber. Dave Kiff at PTG can supply such reamers.
/d

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hitchphil
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Re: Differing Chambers

#4 Post by hitchphil »

20series wrote:if you full length size the cases they should fit any of the chambers then keep them seperate afterwards

Alan
Yea worked that out :bad: & was thinking oh grief 900+ full length resize sign01 vs separate those that fit now - short cut as many are in effect fire-formed to 1 or 2 guns. Was surprised all fitted 2 RPA chambers but not an old P14, a Swing chamber with a proof in Tons/Inch2 & not that surprised they didn't fit a Norma Clark Kreiger on a Barnard ;)

Guess its an excuse to 'hang out' in he shed for a few hrs then.........
Quality control of Scottish Ethanol. & RDX/HMX

& my fav chemical is :-) 1,3,7-trimethylxanthine.......... used to kill frogs.... but widely consumed & in vast quantities by the French? Eh?
Steve E

Re: Differing Chambers

#5 Post by Steve E »

20series wrote:if you full length size the cases they should fit any of the chambers then keep them seperate afterwards

Alan
As Ovenpaa said not always. To ensure that any once fired cases fit my rifles, the first full length resize is always carried out with a small base die. After that I only neck size using a Redding neck die. Every 5th load the cases are put through a body die. All cases are segregated by rifle.
It makes no difference what rifle the chambers are in. The difference is caused by each of the chambers being cut by a different reamer and probably by a different gunsmith. I like to think that rifle chambers can be as different as finger prints. Unles the fired brass is brought back to SAAMI spec or less, case interchangeability can be a problem. So no, RPAs are no different to any other rifle in that they can all be different.
hitchphil
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Re: Differing Chambers

#6 Post by hitchphil »

Dave may have touched on a poss contribution to the reason? both my RPA Q & the club Paramount failed Fred's green sticker test on chamber, both were reamed by HPS to clean the crap out, both passed & went on to do decent shoots. Don't think the other guns have been ream cleaned.... should that make a difference?
Quality control of Scottish Ethanol. & RDX/HMX

& my fav chemical is :-) 1,3,7-trimethylxanthine.......... used to kill frogs.... but widely consumed & in vast quantities by the French? Eh?
Steve E

Re: Differing Chambers

#7 Post by Steve E »

hitchphil wrote:Dave may have touched on a poss contribution to the reason? both my RPA Q & the club Paramount failed Fred's green sticker test on chamber, both were reamed by HPS to clean the crap out, both passed & went on to do decent shoots. Don't think the other guns have been ream cleaned.... should that make a difference?
If you clean your rifle properly you should not need to ream out the chamber. Use a phosphor bronze brush and solvent followed up by flannelette on a chamber stick if you think that there is a build up of carbon. I have never needed to use a brush in any of my chambers. If you need your chamber checking to get a green sticker get an armourer /gunsmith to do it.
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ovenpaa
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Re: Differing Chambers

#8 Post by ovenpaa »

This is why I like my Accuracy International, I am yet to find a factory loaded round or fired case that failed to fit it. At the other end of the scale the M65A we have here has an incredibly tight chamber and the new F/TR rifle we are building is chambered to absolute bottom limit SAAMI .308
/d

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