.220 Russina to 6PPC

S

shinny

Shinny
I have been having a problem with the finished (FF) length of my .220 Russina brass. The cases come out SHORT (1.485 @ best) and I can't figure out if Lapua has made their necks shorter or am I doing something wrong?
This really puzzles me as most smiths recommend trimming 6PPC brass to 1.500-1.505 and I can't even get close. Because I can't get the recommended length I am considering purchasing my own reamer with a CHAMBER LENGTH of 1.490-1.495 to accomodate the shorter brass. If I shoot bullets made on .790 or .825 jackets w/7-8½ Ogives what FREEBORE would be best?
Any suggestions will be greatly appreciated.
 
Last edited:
shinny ...

shinny said:
I have been having a problem with the finished (FF) length of my .220 Russina brass. The cases come out SHORT (1.485 @ best) and I can't figure out if Lapua has made their necks shorter or am I doing something wrong?
This really puzzles me as most smiths recommend trimming 6PPC brass to 1.500-1.505 and I can't even get close. Because I can't get the recommended length I am considering purchasing my own reamer with a CHAMBER LENGTH of 1.490-1.495 to accomodate the shorter brass. If I shoot bullets made on .790 or .825 jackets w/7-8½ Ogives what FREEBORE would be best?
Any suggestions will be greatly appreciated.
Click to expand...

I hope you are NOT neck trimming BEFORE necking up or fireforming.

When I neck up my Lapua 220 brass to 6mm using my K&M neck expand iron the brass always shortens. When I fireform after that, it shortens even further. Once I've fireformed twice I then trim back to 1.500 for uniformity IF I need to. I wouldn't think of doing any trimming until AFTER necking up and AFTER fireforming.

If it's any consolation, I know of one famous shooter who said he deliberately trimmed his brass back to 1.485" because he hated the case preparation process and trimmed to that length because he didn't want to do it as often. :)
 
abintx said:
I hope you are NOT neck trimming BEFORE necking up or fireforming.

When I neck up my Lapua 220 brass to 6mm using my K&M neck expand iron the brass always shortens. When I fireform after that, it shortens even further. Once I've fireformed twice I then trim back to 1.500 for uniformity IF I need to. I wouldn't think of doing any trimming until AFTER necking up and AFTER fireforming.

If it's any consolation, I know of one famous shooter who said he deliberately trimmed his brass back to 1.485" because he hated the case preparation process and trimmed to that length because he didn't want to do it as often. :)
Click to expand...

Here's my process:
RE: Making 6 PPC from 220 Russian

New brass out of the box = 1.516 avg NOT LENGTH TRIMMED

1st time through the SAAMI Full Length Die to Bump Shoulder = 1.515

1st time over the Expanding Mandrel to Neck Up = 1.504

2nd Time through the SAAMI Full Length die to re Bump Shoulder = 1.508

2nd Time over the Expander Mandrel = 1.501

Turned 3 x's to .0086 then fire formed with the bullet seated well into the lands.

After Fire Forming = 1.485
 
Shrinking brass

Hi Skinny,

I must have been lazy when I formed PPC Lapua brass. I expanded the neck, primed and powdered and stuffed a bullet into the case then fired. I left the shoulder alone until the bolt told me to full length resize. I remember seeing cases in the 1.495" to 1.5" range. I didn't mess with trimming until I needed to - back to that lazy stuff.


Russ
 
Shinny,
I agree with Russ. No need to bump shoulder. Expand, turn neck and fire form. Make sure you grease the case slightly with some die wax prior to fire forming. Also try H322 instead of VV133, you can't get enough pressure with that light of a load of 133 to blow the case out very well.
Dana
 
Shinny ...

shinny said:
Here's my process:
RE: Making 6 PPC from 220 Russian

New brass out of the box = 1.516 avg NOT LENGTH TRIMMED

1st time through the SAAMI Full Length Die to Bump Shoulder = 1.515

1st time over the Expanding Mandrel to Neck Up = 1.504

2nd Time through the SAAMI Full Length die to re Bump Shoulder = 1.508

2nd Time over the Expander Mandrel = 1.501

Turned 3 x's to .0086 then fire formed with the bullet seated well into the lands.

After Fire Forming = 1.485
Click to expand...

Just for laughs and giggles try NOT bumping the shoulder back twice and only expand once. I'd be interested to hear what you get then.

How much does that SAMMI die bump the shoulder back? Who makes the die? Have you tried a Harrell's die?

How do you account for the .004" GROWTH after the second F/L sizing following the first neck expansion? You're reporting 1.504" to 1.508". :)
 
If you must bump the shoulder to relieve a bolt closure issue, do it so that you still have a slight feel, and with that you don't have a need to jam the bullet. (I turn,very thinly onto the shoulder, to the full width of the lead champfer of the cutter, to accomplish the same thing.) If you let the bullet jump, and the chamber and brass are completely lube free, that, along with a faster powder (I have used some leftover Benchmark or some 322.) should change your results. IMO bumping farther to try to avoid a doughnut is taking a step to fix a nonexistent problem. With the bullets that we use, their bases are far enough forward to preclude interference with thickening at the neck shoulder junction.
 
No Problem

shinny said:
Here's my process:
RE: Making 6 PPC from 220 Russian

New brass out of the box = 1.516 avg NOT LENGTH TRIMMED

1st time through the SAAMI Full Length Die to Bump Shoulder = 1.515

1st time over the Expanding Mandrel to Neck Up = 1.504

2nd Time through the SAAMI Full Length die to re Bump Shoulder = 1.508

2nd Time over the Expander Mandrel = 1.501

Turned 3 x's to .0086 then fire formed with the bullet seated well into the lands.

After Fire Forming = 1.485
Click to expand...



Shinny, you're not doing anything wrong and you do not have a problem with your brass ending up 1.485 after fire forming. Actually, that tells me you're doing everything exactly right! :)

Most PPC chambers are 1.515 length. Case necks run into the end of the chamber at 1.515, so if your newly fireformed cases are 1.485 you have .030 of room before trimming would be necessary. In my opinion that's perfect and I would not recommend trimming until the length exceeds 1.500 at which point I would trim them all to 1.490 and forget 'em. :p If they reach 1.500 a second time, it's time to retire them.

Some shooters are paranoid about the .030 to .050 length in front of the case mouth and the beginning of the freebore thinking that carbon will build up there and all sorts of bad things will happen. In my opinion, this is nonsense. :rolleyes: Mike Ratigan covers this in his book, "Extreme Rifle Accuracy" and agrees with me; it's not a problem. :)

Good shootin' :D

Gene Beggs
 
Gene says you're doing it right and I agree. You're probably doing more "steps" than needed but each to his own.
 
Borderghost

Did you have to push the shoulder back on the 6.5?
 
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