Chamber gauging 7mm Rem Mag

[walters900]

I measured the chamber tonight of my 7mm Rem Mag tonight with a chamber gauge, I used the Sinclair chamber gauge for the measurements. The only problem I got was the overall cartridge length came out quite a bit longer then the cartridge test lengths that I found in Hornady and Nosler reloading manuals. The reloading manuals hf their overall cartridge lenght in the manuals was 3.29". The number that I came up with was nearly 3.60" overall length (3.599 to be exact). I used a 162 gr Amax as test bullet. I used a piece of brass that had been fired from my rifle, it hadn't been resized yet in any manner, in a previous life the brass held factory Federal Fusion 175gr. This brass has been shot once as far as I know. I guess what I'm curious about, does this measurement sound reasonable or does it sound like it could be off. Thanks

 

[AZShooter]

If you are talking about the Sinclair chamber length gauge
then yes your rifle's end of chamber is long but this is common with factory rifles. Now you know you won't have to trim your brass for a long time and maybe never for the life of the brass.

As for OAL not sure what you are saying. Were you seating the hornady 162 Amax to contact the lands or what? OAL is what you want to make it provided it will not make deep contact into lands which could cause the bullet to stay in barrel should you decide to remove the loaded round. Most loaders prefer to have the most or all of the bullet's bearing surface contacting all of the neck but it is not a hard and fast rule. OAL might be too long to feed from a magazine but many here single load.

Now you know some things about this chamber. Choose a OAL and load it up.

 

[walters900]

Sorry for the confusion. If you've see any of my other posts, I freely admit that I am a reloading newby. I want to set the overall cartridge length so that the bullet touches the lands, then work with my powder charge. Once I had that node found, I was going to go back and work on whether the bullet liked to be touching the lands or liked a jump. I put up another post asking those who have loaded 162 Amax about how far off or into the lands it likes to be loaded, but haven't seen any responses yet. Thanks for your response.

 

[pikeman]

I have shot the 162 amax, and your number sounds close to mine. Mine liked 10 thou off the lands.

 

[walters900]

The whole reason that I started this thread was my concern that I might be measuring wrong, simply because it the chamber measurement seemed a lot longer than the test cartridge length of 3.290" that hornady has in it's reloading book. So my concern was that I was measuring long.

 

[bigedp51]

posting error