Hi guys im new to pistol reloading. I fired 7 158gr magtechs took the brass out and all had a swell at the bottom right above the rim. I was wondering if anyone might know why. I fired a 125gr winchester a 158gr magtech and a reloaded 38special. and the 158gr magtech swelled the 38 didnt and 125gr had a very slight swell. Is it because the 158gr is a heavy load. thanks in advance. I forgot all of these were fired out of a a 1yr old taurus 357mag

You need to be able to quantify the amount of expansion.
If the case is expanded only above the solid head and is expanded only .002 to .003 you have pretty mild pressures. I would be concerned if your ammo is expanding more than factory ammo.

Check some factory loads with a micrometer and compare them to your hand loads.

Might be the chambers on the Taurus are a bit loose (large).

Were you shooting .357 Mag loads or .38 special loads? Most .38 special loads are very mild and shouldn't affect the brass at all.

.357 loads are a different matter. When I used to have a S&W Model 66 the 357 loads beat the crap out of my hand even with its big grip.

Take a micrometer (if you don't have one, get one - it is one of my most used tools when reloading) and mic the chamber of your cylinder. It should match the base of your cases pretty close. I don't have my Model 66 anymore or I'd check mine for you.

sorry I didnt word it better the magtechs were factory ammo and it swelled enough I could see and feel the swell. the 125 was also factory ammo. the 38sp was a reload but it didnt swell the only one that swelled was the factory 158gr magtechs thanks for the quick reply

that knida makes sense I had some reloaded 38shorts that would easily fit in my gun but tried in 2 friends guns and they would not even come close to going in.

I heard that some Magnatech ammo is on the hot side. Might be the case with your batch.

will the swelled brass be ok to reload

they call it pressure.
it is fine to reload and use again.
the swell is where che is measured.
if you know the pressure of the round and measured the swell you could use it to measure other rounds fired in the same lot of brass to make estimate the pressure of those rounds too.

ok thanks for all the replies