I have a Euro. cape gun. Rifle is 8x57S....that's understood. But shotgun barrel is unmarked. It is 16 ga. An unfired 2.75 shell goes in effortlessly. But....to determine whether effective chamber length is that or shorter......do I feel with a "pick" for any change in sidewall....then measure pick??.....do I insert a dowel of same diam as 16 ga. shell and feel for resistance....then measure dowel to point of 1st resistance?????....please advise.
Thanks
Alex

Yup.....I know.....but seriously.....there is NO indication of chamber length......irrespective of the fact that there MUST be!! Barrels have been examined under magnification everywhere. There is a "16/1" under the barrel flat, as well as a couple of Belgian nitro proof marks.

Do a chamber cast. Brownell's, Midway and who know who else sells a kit.

Could someone have lengthened the forcing cone??

http://www.brownells.com/.aspx...HOTGUN_CHAMBER_GAUGE
or you could just shoot 65mm / 2 1/2" shells in it and not worry about it.
If your gun is prewar then modern shells have more pressure and will be tough on the gun regardless of the org chamber length.
Here is a source of 2 1/2" shells
http://www.rstshells.com/

Kebco....thanks.
Is it reasonable (since I want slug or buck loads) to remove the shot from a 2.5" 16 ga. shell and load with a slug or #1 buck???

Sorry but I am a poor source for info on what is safe or not when it comes to reloading shotgun shells. (I know my limitations!)
I would guess that 1oz of buckshot would have the same pressure as 1 oz of birdshot if the shot takes up the same amount of space in the case but you need to confirm this with someone that knows more about shotgun shell loading and effects on pressure than I do.

I went to the Brownell's site, and ordered their booklet on determination of chamber length. Also, they sell a cylinder for chamber length determination. Will read their book, and order the cylinder.
Thanks all.
Alex

Ouch! Remember all OLD TIMEY shot gun shells used a roll turn over.

So...and this became a problem in England as well...any modern crimp closed 2 3/4" shell will almost always fit into a standard 2 1/2" chamber.

A good rule of thumb is that if it doesn't say OTHERWISE it is a 2 1/2" or 65mm chamber.

And here in "Yurrup" 2 3/4" chambered 16s were really very, very uncommon. In fact they still are.

Another great source for shorter, low-pressure shells is Polywad in middle GA. www.polywad.com

Steve

quote:

Originally posted by enfieldspares:
Ouch! Remember all OLD TIMEY shot gun shells used a roll turn over.

So...and this became a problem in England as well...any modern crimp closed 2 3/4" shell will almost always fit into a standard 2 1/2" chamber.

A good rule of thumb is that if it doesn't say OTHERWISE it is a 2 1/2" or 65mm chamber.

FWIW, In 12 gauge, if the gun has 2 1/2 chambers, you can still shoot 2 3/4 ROLLED crimp (CIC approved) shells through it.

I was given that little snippet of info about 20 odd years ago from the Chairman of Eley and recently confirmed it by emailing the company.

I have also on occasion used 2 3/4 star crimps as well (in my 1926 John Dickson & Son SLE) but it blows the end off the case where it hits the forcing cone and according to Eley, isn't to be recommended.

You need to watch the pressure. Many 2 3/4" loads generate far to much pressure for old guns with short chambers and even those with longer chambers.
Many of the promo loads you see advertised cheap around hunting season are death to old guns. They often generate 2X the pressure that old shells were loaded too so that they will function through ever BS auto loader ever made.