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sasu
12-19-2007, 07:57 AM
Would you know where to find the SAAMI and CIP headspace specifications for 454 Casull?

The reason I am asking is my new Legacy 92 454 Casull failed a European CIP inspection because of too little headspace. I do not know yet which measurement is not correct: the distance between bolt and chamber or the chamber length.

I was wondering if the Legacy 92 has e.g. headspace or chamber dimensions on purpose at the SAAMI minimum and maybe it is too little according to CIP specifications. Or did I just get a faulty gun?

faucettb
12-19-2007, 10:38 AM
I haven't found a site with those specs, but here is an article on head space.

http://www.surplusrifle.com/shooting/headspace/index.asp

You might check with some of the Reamer rental places and with Brownell's. Brownell's sells headspace gauges and reamers and their tech section may be able to give you the measurements your looking for.

WyrTwister
12-19-2007, 11:11 AM
Would you know where to find the SAAMI and CIP headspace specifications for 454 Casull?

The reason I am asking is my new Legacy 92 454 Casull failed a European CIP inspection because of too little headspace. I do not know yet which measurement is not correct: the distance between bolt and chamber or the chamber length.

I was wondering if the Legacy 92 has e.g. headspace or chamber dimensions on purpose at the SAAMI minimum and maybe it is too little according to CIP specifications. Or did I just get a faulty gun?

The .454 HS'es on the rim . Personally , if the bolt / leaver closes OK on factory ammo ( and I think this can vary from brand to brand ) , I would not worry about it .

Only thing I can think of is it might get cranky to operate if you let it get pretty dirty .

Wyr
God bless

sasu
12-19-2007, 12:02 PM
I would not worry about it.

The problem is the rifle will not be released for sale if it does not pass the CIP certification.

I found CIP specifications for 454 Casull:

Chamber length minimum 1.407".
Headspace from chamber to bolt face 0.060".
Cartridge case length maximum 1.398".
Cartridge rim thickness maximum 0.060".

Now to find equivalent SAAMI specifications.

I am getting a suspicion the chamber is reamed to a reasonable length of around 1.390-1.400", but the CIP specs call for a generous 1.407". All my loading manuals give a max shell length between 1.385"-1.390", which is less than the CIP length of 1.398". The problem might a case of two different standards and the gun reamed to a minimum SAAMI length and then measured against the CIP standard.

WyrTwister
12-19-2007, 12:49 PM
The problem is the rifle will not be released for sale if it does not pass the CIP certification.

I found CIP specifications for 454 Casull:

Chamber length minimum 1.407".
Headspace from chamber to bolt face 0.060".
Cartridge case length maximum 1.398".
Cartridge rim thickness maximum 0.060".

Now to find equivalent SAAMI specifications.

I am getting a suspicion the chamber is reamed to a reasonable length of around 1.390-1.400", but the CIP specs call for a generous 1.407". All my loading manuals give a max shell length between 1.385"-1.390", which is less than the CIP length of 1.398". The problem might a case of two different standards and the gun reamed to a minimum SAAMI length and then measured against the CIP standard.


I am sorry , but I am confused .

First , what country are we talking about .

Second , you may be correct about different chamber dimensions . But Head Space on rimmed calibers is measured at the rim . I have a .303 Brit and 7.62 x 54R HS no-go . Both HS on the rim and the body of the guage is very short , not nearly the length of the whole brass .

I suspect the same is true for .454 ?

So , is the issue HS or is it chamber dimension . Perhaps HS guages are made different oveseas ?

God bless
Wyr

sasu
12-19-2007, 01:01 PM
I do not know yet if the bolt to chamber dimension is too short or if the chamber is reamed too short. I will find out in a couple of days.

If it is just a difference between SAAMI and CIP chamber dimensions, I will probably try to get the gun papered to a wildcat cartridge, e.g. 45 OhDear. Then the gun should not be required to meet CIP standards.

I ordered a couple of books from SAAMI to see what the specifications are, but it will take a week or two for me to receive the books. I was hoping someone could post the 454 Casull SAAMI chamber length and bolt to chamber clearance while I wait for my books.

I am in Finland.

sasu
12-20-2007, 12:14 PM
It seems the rifle has a slightly too tight chamber and does not allow full gauge entry. The chamber will be reamed as soon as a suitable reamer arrives.

The gun can be fired, but does not pass this test.

I wonder if the chamber has been made tight on purpose, to extend brass life. I know we are having problems with custom made benchrest rifles where the chamber is reamed to minimum dimensions for accuracy and case life and then it is not accepted in CIP testing and has to be re-reamed.

WyrTwister
12-26-2007, 02:28 AM
It seems the rifle has a slightly too tight chamber and does not allow full gauge entry. The chamber will be reamed as soon as a suitable reamer arrives.

The gun can be fired, but does not pass this test.

I wonder if the chamber has been made tight on purpose, to extend brass life. I know we are having problems with custom made benchrest rifles where the chamber is reamed to minimum dimensions for accuracy and case life and then it is not accepted in CIP testing and has to be re-reamed.

If you can get your hands on it & if it functions OK , I would leave it as is .

The .454 is a 65,000 psi caliber and I think you are going to need everything you can get to keep the brass from streaching too much ?

God bless
Wyr