FORMING BRASS PROBLEM

[woodnut]

Recently, I have enjoyed shooting a 20 PPC. I took Lapua 220 Russian and necked it down and fireformed it. No problem. I just found an old stash of 220 Russian by Sako and tried to do the same. Problem arose!
When I sized those cases down, they would not hold the bullet! I had to find a much smaller sizer button that just barely held onto it.
You would think sizing down would make a tight enough neck, right? All I can think of is that the brass wall is much thinner in Sako. Have not miked it yet. Thought I'd ask if anyone has seen the same problem and what should I do.

 

[J E Custom]

Recently, I have enjoyed shooting a 20 PPC. I took Lapua 220 Russian and necked it down and fireformed it. No problem. I just found an old stash of 220 Russian by Sako and tried to do the same. Problem arose!
When I sized those cases down, they would not hold the bullet! I had to find a much smaller sizer button that just barely held onto it.
You would think sizing down would make a tight enough neck, right? All I can think of is that the brass wall is much thinner in Sako. Have not miked it yet. Thought I'd ask if anyone has seen the same problem and what should I do.

Lapua brass cases are typically thicker than other brands of brass and require different sizing sometimes.

I would do like you said and mic. the neck thickness first and then would look into a set of bushing dies if you are going to run different brands of cases. it is easy to adjust the neck tension with bushings
that are very inexpensive.

You do have/need to mic.the wall thickness to purchase the correct bushing though.

Good luck

J E CUSTOM

 

[woodnut]

Hehehe, I just found my other stash...of Lapua brass! Now I can proceed with that and in spare time work on Sako brass, if needed.

 

[L.Sherm]

You may try annealing after sizing down and run through your FL size afterwards, you could be getting alot of spring back also.