Seating with 21st Century Hydro Seater

[robinzon]

Hello all,

I finally got my hands on the 21st Century hydro bullet seater and a Wilson 6mm BR die (from a member here - I do not know what kind of stem it has in it ). I have virgin Lapua brass and 105gr Lapua Scenars. I try to seat the scenars and this is requiring too much pressure and the bullets have a mark from the stem. Now again this is virgin brass, I can expand the necks with an expander mandrel and neck size with a bushing but virgin brass should not need this much pressure to seat. Any ideas?

 

[JFrank]

Expand the necks and dry lube prior to seating or use the ram style the first time

 

[creedfan]

virgin lapua 6br brass has extremely tight necks. use a Expander mandrel and life will be good.

 

[robinzon]

virgin lapua 6br brass has extremely tight necks. use a Expander mandrel and life will be good.

thanks I did not quite have that problem with 308 virgin lapua brass but good point... this goes to show you how little attention we pay to this using high leverage presses

 

[Falfan2017]

thanks I did not quite have that problem with 308 virgin lapua brass but god point... this goes to show you how little attention w me pay to this using high leverage presses

Yes the hydro seater was eye opening. Before I got it I had some loads that must have been at least 150 psi. Just didn’t think much about it on a leveraged press. Groups improved significantly with the hydro

 

[1shot]

I have had several batches of 6br Lapua brass that were really hard right out of the box. Annealing, then expand and size with a bushing die solved the problem. Oh yeah, I love my 21st C. hydro press. It helps you sort out that occasional hard or soft seat that will open a group up in a flash.
I hope this helps,

Lloyd

 

[Petros284]

Give a .2425” Expander mandrel a shot on that new brass and will help out a ton!

 

[robinzon]

Give a .2425” Expander mandrel a shot on that new brass and will help out a ton!

I expanded with K&M mandrel then used a .268 bushing.... wound up with around 60 psi of force still not satisfactory IMHO.... Frankly I don't see the actual mandrel size on their website.... Sinclair is .242 and I have that die as well though I like K&M hard stop screw... I will measure the K&M and compare... and also the 21st Century expanders (which I think same exact diameter as Sinclair as he uses Sinclair stainless but his own carbide)....