fireforming query

[1967spud]

hi there i have now come to the point where i need to fireform some new lapua cases for my .243 ack at the moment for the formed cases i am using is 80g nosler and 40g of varget.

 

my question is , could some body please reccommend a load for this case for fireforming possibly using that bullet and powder as i have them in stock

 

 

thanks

 

 

also using new brass would the oal be the same in un-fireformed cases as compared to fireformed cases ,. if that makes sense

 

 

thanks mark

[Guest varmartin]

Use the same load as you have been using, but seat the bullet to jam in the lands ( if you can with that 80 nosler ) so the case sits tight against the bolt face.

 

The OAL will remain unchanged as it is measured from case face to bullet and does not account for shoulder changes.

[1967spud]

thanks for quick reply martin do you mean that the measurement to the ogive will the same or fractionally longer

 

so that the bullet is touching the lands

[Guest varmartin]

Your Ackley chamber will have totally different specs compared to your old .243 win chamber so you will need to find your Chamber measurement to the lands.

 

Take one of your old .243 cases and soft seat a bullet in the case. ( do not size the neck , just pinch it a bit to hold a bullet ) cycle this round carefully.

 

measure the OAL of this dummy round and add 0.010 and load your `to be fire formed rounds` to this length.

 

Your loaded rounds should now be in the lands or tight to the lands thus keeping the case face in contact with the bolt face.

 

You should get perfectly formed AI cases when fired.

 

NOTE

 

If your chosen bullet cannot be loaded to reach the lands there are other ways to form new cases, but it involves necking up your brass to the next size to create a shoulder in the neck to stop the case going to far forward..

 

I would recomend ` googling` .243 Ackley fire forming` and reading as much as you can on the subject.

[Ronin]

Also use near max book loads for that weight of bullet (max load in the NON ackley case) it forms the cases better with sharper edge at the junction of the neck and shoulder.

 

As Martin says, jam bullet into lands so that rear of case is touching boltface.