when do you need to case trim? I am reloading some .303 once fired brass for my ross but I don't have a trimmer. do you think I will need one or will I be okay? I know why you use a trimmer but at what point would cause the case to elongate?
case trimming
- Thread starter JTF#
- Start date
Check out the SAAMI specs for your cartridge with a caliper. There is a max case length recommendation. If your cases exceed that length, you will need to trim it back to the recommended trim length. If you are reloading for bottle neck ammo, a trimmer is a necessary tool to have.
samsplacci71
Regular
- Location
- Toronto area
O/P, you have your answer. My preference is to measure the once fired brass since it is mixed with different headstamps (mfg). I separate those within tolerance and trim those which are longer.
Knottybuoy
CGN frequent flyer
- Location
- Vancouver, BC
I average 3 firings from Factory brass before they need to be trimmed. Measure them with calipers, 56.44mm/2.222" is the max case length.
Get a Lee case conditioning set from Henry at Budget Shooter Supply and the length guage and shell holder for .303 and you can't go wrong. Dont put over-length cases in your rifle and fire them!
Get a Lee case conditioning set from Henry at Budget Shooter Supply and the length guage and shell holder for .303 and you can't go wrong. Dont put over-length cases in your rifle and fire them!
What could happen is the case mouth jams into the rifling and pinches the bullet, raising pressure. To the OP: when you need to trim will vary with sizing methods. Neck sizing doesn't stretch the brass as much as FL sizing. Sizing down to the shell holder every time will stretch the brass more than bumping the shoulder back. With neck sizing you probably won't need to trim until you bump the shoulder back and at that they usually don't need much. This will of course vary with different cartridges and brass. I prefer to trim after sizing as case lengths will vary some if trimmed before sizing. Again this can vary with different cartridges and brass.
There are so many variables as to how much an individual case may stretch on firing/resizing, the only prudent (safe) way to reload is to measure (after sizing) every one of them, every time.
Think of the spike in pressure that will surely result from one of your bullets being locked in by the bolt jamming a too long neck forward into the tapered leade?.
All you need is a dial caliper, a cheap one will do, and the max. case length spec. for that cartridge.
The inexpensive lee trimming system works well, & even better, if you power it with a drill/driver and lee's spud attachment.
A deburr in and out .... done.
Think of the spike in pressure that will surely result from one of your bullets being locked in by the bolt jamming a too long neck forward into the tapered leade?.
All you need is a dial caliper, a cheap one will do, and the max. case length spec. for that cartridge.
The inexpensive lee trimming system works well, & even better, if you power it with a drill/driver and lee's spud attachment.
A deburr in and out .... done.
"...If they are too long, trim them..." And it's that simple. You trim when the cases are too long. Usually stretch the most upon the first firing. Quick check with a calipre set to the max length given in your manual(they will lock), every time, but you won't to trim every time.
"...don't trim my pistol cases..." Pistol cases rarely need it.
"...don't trim my pistol cases..." Pistol cases rarely need it.
I bought a wft trimmer for 223 after the failure of 3 lee trimmers for 223, one failed after 100 cases on a drill at 500 rpm.
Lee trimmers are ok for low speed low volume i guess.
Wft trimmer is the best for the money, imo. Fast, 1500 rpm, shoulder length, i trim with a case in each hand, i can trim a case every 3 seconds or so. 1000 cases under an hour. Faster to process all cases than to try to measure with a caliper.
The only better option would be on the press dillon trimmer or giraud because it will debur same time. (Both more expensive)
I have a lyman hand trimmer for low volume higher precision cases.
Lee trimmers are ok for low speed low volume i guess.
Wft trimmer is the best for the money, imo. Fast, 1500 rpm, shoulder length, i trim with a case in each hand, i can trim a case every 3 seconds or so. 1000 cases under an hour. Faster to process all cases than to try to measure with a caliper.
The only better option would be on the press dillon trimmer or giraud because it will debur same time. (Both more expensive)
I have a lyman hand trimmer for low volume higher precision cases.
If the Lee trimmers are wearing out its because you're pushing way too hard. I've got about 1500 rds thru one .223 case length gauge and its still good. And IIRC the WFT chamfers if you rotate the case in the trimmer after its done trimming.
Your size makes no difference as it doesn't take a terrible amount of force to start wearing that pin when its hitting a spinning drill chuck. I wait until the torque feedback backs off which tells me I'm done trimming. When trimming high volumes of brass at decent RPM it really doesn't take much. Just another caveat of Lee equipment.
Don't reload for others, it's not worth it. If something bad happens guess who they blame.
If you are going to do it then do it right and measure every case and trim them all (I do it after sizing) so they are all the same and within spec.
If you are going to do it then do it right and measure every case and trim them all (I do it after sizing) so they are all the same and within spec.
