Case Length and what have you

[larzb93]

i am newer to reloading and i am reloading .308. i do not know how to find my trim to length. or once i find my OAL what do i do with it? i need some help with making the rounds unique to the rifle. i understand the bullet seating depth, i guess you could say im a bit with stuck case length. whats too long? whats too short? how to i make custom trimmed round without damaging my rifle. THANKS

 

[mrawesome22]

Look in your manual. It will give you the trim to and max case length.

 

[Dave R]

And you will need either a case trimmer, or a case trim die and file, to get them to the right length.

Centerfire rifle cases grow in length as they are fired. If they get too long, it can cause problems. If you "jam" a too-long case into the chamber, the excess length acts like an extra-strong crimp, and drive up pressures to dangerous levels.

Gotta trim.

 

[larzb93]

what about the special tool that Sinclair makes to find custom case length? how important is it to have custom case length?

 

[mrawesome22]

No such thing as custom case length.

If you mean cartridge length, do a forum search for "hacksaw".

 

[brickeyee]

No such thing as custom case length.

If you know the actual length of the chamber you can use that to determine trim length instead of just the 'standard' length.

 

[F. Guffey]

Along with cases I formed to determine the length of the chamber from the bolt face to the shoulder I also forms cases to determine the length of the chamber from the bolt face to to the end of the chamber and beginning of the forcing cone, I want to cover all the chamber with the case if possible. When forming wildcats some cases shorten .040 thousands, the shorter neck reduces bullet hold and exposes part of the chamber (neck) (depending on how the chamber is cut) to hot high pressure metal cutting gas, do I want to EXPOSE THE CHAMBER TO EROSION? no, so I go to the trouble of eliminating it.

F. Guffey

 

[F. Guffey]

and as I have said, I have one rifle with .016 thousands head space, these things do not lock me up, all I have to determine is ‘where to add the additional length.

F. Guffey

 

[mikld]

Perhaps you are looking for the overall length of your reload to "customize" the bullet seating depth as related to the lands of the rifling? The tool you saw is the tool for determining the distance from the bolt face to the lands for determining the seating depth/OAL....

 

[243winxb]

Double post, sorry

 

[243winxb]

308 Win. Trim Length & Finding OAL Or COL as i call it.

When case length reaches 2.015" it gets trimmed back .010" to 2.005" This is done mostly after full length resizing. The COL for the round can be found by different methods. This will work & is free. >

I find the COL by pinching the fired case neck with plyers. Place bullet in case mouth at the longest setting. Insert dummy round into rifle. Extract dummy while holding case with fingers so the ejector does not push it against the side of the receiver. Do this many times till you get the same COL measurement. For hunting, set the bullet at least .010" deeper or till dummy round fits the magazine.