How many times can you fire before...

[bryceh12321]

How many times can you fire a single cartridge before you have to start trimming? How long does it take for brass to stretch out and you have to start trimming? Thanks.

[tom234]

What cartridge ?

[bryceh12321]

reloading 30-06, and 300 win mag.

[tom234]

What cartridge ? Straight walled pistol cases don't stretch and sometimes shrink a bit

[kraigwy]

Depends on how they are loaded, the condition of the chamber, the amound of re-sizing of the brass, etc etc.

Best to check the brass before reloading.

[LHB1]

Depends on the cartridge, more specifically on the pressure level of cartridge and whether bottleneck or straight case. I have never trimmed any .45 ACP brass. I have trimmed .357 Mag and .44 Mag brass so the cases would be same length and thus roll crimp consistently. With rifle brass I have only trimmed brass when new to make them all the same length. Have not had to trim again but then I don't shoot rifles much these days after having a torn retina some years back.

[ISC]

There are alot of variables. If you always shoot the cases out of the same gun with a tight chamber and only case neck resize they'll stretch alot less than if you shoot out of a looser chamber and full length resize.

[Unclenick]

For .308 and .30-06 I used to trim back an extra 0.005" and let them grow 0.015" from there before trimming again. Every 3 to 5 rounds, depending on the bullet and load. Then I got a Giraud trimmer and now I do it right to spec every time I reload, since it only takes a second. That way, if I want to crimp I'm not having to adjust the crimp die for the portion of the trimming cycle the cases happen to be in.

[Slamfire]

I trim rifle brass on the first darn firing. Because I have a Gracey and a Giruad, I trim new .223, 308 and 30-06 on the first reloading.

I found out early on that brass lengthens the most on the first firing. The stuff will just grow to an excessive length. And it needs to be trimmed.

[Dennisp]

I trim everytime I reload. I don't mind doing it.

[azredhawk44]

In an autoloading rifle such as a Garand, the .30-06 cartridge will stretch more because it is hot during extraction and obturating against the chamber at the same time.

You'll have to trim every other loading, maybe once every 3 loadings if you trim back far each time.

In a bolt action where you give the chamber a few seconds to cool before extracting and do so in a gentle manner, you will be able to shoot more often between trimmings.

I have a .30-30 lever gun that for the first several years I didn't trim at all for it. Probably did 5 loads for the brass I had, never trimming. Granted, it's lower pressure than .30-06, but hopefully that helps some.

[wncchester]

"How long does it take for brass to stretch out and you have to start trimming?

Best answer to a question like this is to monitor your own cases and trim them when they need it. How large your chamber is and how you resize will be the major contributing factors. I doubt my figures, or anyone elses, would do a thing to help you with that!

[dardascastbullets]

Bryce,

The answer depends on the pressures to which you load your brass. If you load cast bullets (mild loads) your brass will never require trimming. Then to the other extreme, stout loads will cause the brass to flow forward, requiring the brass to be trimmed periodically.