Trimmed a little short

[bob_dobalina]

I inadvertently trimmed my 300 WSM brass to 2.087, min trim length is 2.090. Will I see any negative effects? Thanks guys

 

[DrMike]

You'll be fine. The brass will quickly stretch back. Three thousandths of an inch won't be a problem with holding the bullet.

 

[Richracer1]

I use some of the RCBS "X" full length sizing dies and the instructions say to clean the brass, then size all the bras. You then trim to ensure the brass is all equal length. One that is done, you then trim to .020 shorter than maximum specs. Then adjust the die to the newly trimmed brass. It's suppose to limit the growth of the brass.

 

[300WSM]

I inadvertently trimmed my 300 WSM brass to 2.087, min trim length is 2.090. Will I see any negative effects? Thanks guys

Been there done that. Not sure how you got there but mine has happen(s) from over powering the case trimmer past the stop with my right arm.

You won't have any adverse issues at .003 below. Nothing whatsoever...
I've several rifles chambered in the greatest caliber ever made... 300WSM... and have loaded thousands of rounds in just that caliber alone.

You're only .003 below the "trim to" of 2.090 and it's nothing to worry about whatsoever.

 

[hunter24605]

Someone please correct me if I'm wrong. Regarding Max, Trim, and Min case lengths, I was told that the "trim to" is Max - .010", Min is Max -.020"
Just using the 300 WSM as reference, I would have assumed:
Max: 2.100"
Trim To: (2.100" - .010 ) = 2.090"
Min: (2.100" - .020) = 2.080"
And trimming below the "trim to" is fine, so long as you don't go under the Min length, and more importantly is to trim them all the same.
Please chime in and set me straight if I have it wrong.

 

[ShadeTree]

Someone please correct me if I'm wrong. Regarding Max, Trim, and Min case lengths, I was told that the "trim to" is Max - .010", Min is Max -.020"
Just using the 300 WSM as reference, I would have assumed:
Max: 2.100"
Trim To: (2.100" - .010 ) = 2.090"
Min: (2.100" - .020) = 2.080"
And trimming below the "trim to" is fine, so long as you don't go under the Min length, and more importantly is to trim them all the same.
Please chime in and set me straight if I have it wrong.

Correctamundo. If you look at Saami cartridge drawings, they will show the case length, (minus .020.) 30-06 for example is shown as 2.494-.020.

I'll go a step farther. If you'd happen to trim a couple of cases short, say .030-.035 below saami max, I see no reason not to even the rest of them up to match for the time being. Now in a cartridge say like the 300 Savage with a short neck, you're just robbing yourself of precious neck length, but in many cartridges there would be no harm, no foul if you accidently went short. There's no reason to, but it also wouldn't hurt anything. More important to me is to have them equal lengths.

Same goes for the other way, the max is set to ensure that cartridge wont be in trouble in any chamber. However most chambers you can go well past that. But of course a person cannot assume that without being able to accurately check it.

 

[ShadeTree]

I will add as to why I said for the time being, if cases are trimmed too short. Meaning short term and you can let your cases grow out from there. Reason being in my mind is that you would risk a carbon deposit or ring forming out ahead of the exposed area in the neck of the chamber if you continually kept them short, then later if you switched to normal or max length cases, you could have immediate high pressure.

I will admit that I don't have a handle on exactly why or when carbon build up will show up. Seems some cartridges are more prone to it, as well as some powders are said to be worse, or bad for it. Cannot confirm that personally but doesn't mean it isn't true.

 

[hunter24605]

I will add as to why I said for the time being, if cases are trimmed too short. Meaning short term and you can let your cases grow out from there. Reason being in my mind is that you would risk a carbon deposit or ring forming out ahead of the exposed area in the neck of the chamber if you continually kept them short, then later if you switched to normal or max length cases, you could have immediate high pressure.

I will admit that I don't have a handle on exactly why or when carbon build up will show up. Seems some cartridges are more prone to it, as well as some powders are said to be worse, or bad for it. Cannot confirm that personally but doesn't mean it isn't true.

I agree, and for a measly $6.00 for a chamber length gauge, it’s a no brainer to get them and know exactly where to trim.

 

[ShadeTree]

I agree, and for a measly $6.00 for a chamber length gauge, it’s a no brainer to get them and know exactly where to trim.

Yep or at least check with a borescope if you want to color outside the lines on max/min case length. It wouldn't tell you the exact distance but would let you see if you got room to spare yet even if cases are over length.

I never paid that much attention to chamber drawings, only cartridge drawings. But I see on the 30-06 for example minimum chamber length for the end of the neck is 2.502. Maximum factory case length or reloading manual length is 2.494. So they are allowing just .008 clearance as deemed safe on a maximum length case in a minimum length chamber. A person wouldn't want to push the issue without knowing exact lengths, but a peek with a borescope on a chambered empty can tell you real quick if you got way more than .008 yet on a case that is over length.

 

[PJGunner]

"Will I see any negative effects?"
No.
Paul B.