When to trim?

[Joey Dean]

With the Giraud and the Little Crow trimmers both indexing off the shoulder, do you only trim to length after a shoulder bump?

I have my 223 setup in a 650 with a FL resize in station one and a Dillon 1200 in station 4 so they are FL resized and trimmed every trip through. With my bolt guns this will not be the case. Educate me if you would.

 

[afrancke]

With the Giraud and the Little Crow trimmers both indexing off the shoulder, do you only trim to length after a shoulder bump?

Exactly right. Get your sizing/bumping over with and then trim.

 

[thrusty]

I don't personally have one of the trimmers you mention...However, it is good practice to trim after you size as brass typically grows after you FL size.

 

[Trigger Time 23]

Always trim after sizing as the length of brass changes as mentioned above.

 

[varmint slayer]

Always trim after sizing as the length of brass changes as mentioned above.

Only if you are mega anal. For practical shooters, trimming after each sizing is like wiping your ass before you shit. There is no need to as there is a safe case length for each caliber and more accurately each gun. With a factory chamber you would be surprised how long you can go before the need to trim arises. Also if you are only bumping the shoulder back .002 or so every firing, the brass shouldn't grow much every sizing.


http://mobile.sinclairintl.com/mobile/aspx/search/product.aspx?pid=32925

 

[afrancke]

Only if you are mega anal. For practical shooters, trimming after each sizing is like wiping your ass before you shit.

I don't believe the question was, "should you trim each time you size;" it was more like, "when you do trim, is that before or after sizing."

So, I don't disagree that you needn't trim each time to stay within cartridge specs or the (more generous) dimensions of your rifle's chamber, but that is a separate issue. TMIMITW might say:

 

[Trigger Time 23]

Only if you are mega anal. For practical shooters, trimming after each sizing is like wiping your ass before you shit. There is no need to as there is a safe case length for each caliber and more accurately each gun. With a factory chamber you would be surprised how long you can go before the need to trim arises. Also if you are only bumping the shoulder back .002 or so every firing, the brass shouldn't grow much every sizing.


http://mobile.sinclairintl.com/mobile/aspx/search/product.aspx?pid=32925

Agreed, I should have been more clear. If you are going to trim, do it after sizing.

 

[varmint slayer]

I don't believe the question was, "should you trim each time you size;" it was more like, "when you do trim, is that before or after sizing."

So, I don't disagree that you needn't trim each time to stay within cartridge specs or the (more generous) dimensions of your rifle's chamber, but that is a separate issue. TMIMITW might say:

View attachment 6066

lol agreed brother. Just thought that I would clarify that so that it wouldn't get taken the wrong way.

 

[Joey Dean]

Let me clarify my question a bit then.

Every time I shoot my bolt guns there is a bit of growth that will culminate with an eventual need to bump the shoulder back. During this time your case necks grow a bit as well. So, is there a need to trim necks, knowing that this will be off of a "new" datum line from your moved forward shoulder, between shoulder bumps?

I currently do not and only trim when I resize.

 

[afrancke]

You'll need to measure your brass after bumping to really know for sure. As a rule I have not seen large amounts of growth from either bumping or resizing 308 cases so the case for trimming depends on the approach you are using for trimming overall to begin with:

1) trim only when absolutely necessary (because max length is exceeded), and then trim a lot to extend the time between trimmings

2) trim every time to promote consistent case volume

3) something in between

Personally, I'm not trimming when bumping shoulders generally but then again I don't use that approach much outside of reloading at the range; usually FL size at home.

 

[scatterbrains]

I trim every time i resize, just a habit if the case doesent need to be trimmed the trimmer wont do anything so its not really a big deal.

With a tight chamber or an autoloader i believe case length is quite important. I dont have alot of lee way in the case length for my AR it has a very very tight chamber (custom barrel)

 

[Crus75]

25-06, body size, neck-size; trim; 2.487".

Fire 1x , case grows .002-.003, neck-size; case grows .002-.003. Case length = 2.493" (Chamber length = 2.495")

must trim.