Does gas check on GC boolit prevent brass sizing boolit?

[autopilotmp]

Just received my first GC boolit mold (Lee 225-55 FN). I know that with my 9mm I had to get a larger expander plug for my powder thru die so that the brass wouldn't size down my boolit. I have not received my gas checks yet but thought I would make a couple dummy rounds to check mag and feeding. My brass of course sized the naked boolits down to @ .2235. Then of course I was trying to figure out how I was going to expand the neck to make these boolits fit. Then I seated a jacketed bullet in a case and pulled it, then I seated a cast boolit and it came out the exact same size as the jacketed bullet. This is where my question comes from. Any help with this or suggestions on what to do if the GC does not prevent the boolit squish is much appreciated.

[Dusty Bannister]

Perhaps this thread will help you understand what need. The Lyman M die expands the neck to a desired and consistent diameter. The Lee tool only flares the opening so does not prevent neck tension from sizing the bullet down further.

http://castboolits.gunloads.com/show...ersal-expander

[FredBuddy]

I've started using the NOE expander plugs and bushings. They come in a myriad of sizes and should meet most needs to maintain appropriate neck tension, yet not squish your cast boolits below what you need for your application. And the price is right!

[.22-10-45]

In my Hornet, I find I can use a tighter neck using g.c. than with p.b. bullets. pulled bullets show no reduction in dia.

[rupe01]

+1 with Fredbuddy....the NOE expander plugs are cheap and fit in the Lee Universal Expander die and do a great job!

Sent from my Nexus 7 using Tapatalk

[JonB_in_Glencoe]

Just received my first GC boolit mold (Lee 225-55 FN). I know that with my 9mm I had to get a larger expander plug for my powder thru die so that the brass wouldn't size down my boolit. I have not received my gas checks yet but thought I would make a couple dummy rounds to check mag and feeding. My brass of course sized the naked boolits down to @ .2235. Then of course I was trying to figure out how I was going to expand the neck to make these boolits fit. Then I seated a jacketed bullet in a case and pulled it, then I seated a cast boolit and it came out the exact same size as the jacketed bullet. This is where my question comes from. Any help with this or suggestions on what to do if the GC does not prevent the boolit squish is much appreciated.

"Does gas check on GC boolit prevent brass sizing boolit?"

The answer your question is maybe.
Typically I use a harder alloy for rifle, so the hardness as well as the GC do minimize a boolit being swaged down by case mouth tension.
Are you casting with COWW or softer, for use in 22LR equivalent loads? if so, you will probably see the problems you are currently talking about...and, as mentioned, the Lyman "M" die or the NOE exaplnder plugs that fit in the Lee universal flare die are the solution to getting proper neck tension.
Also, how long have your bullets aged? An alloy like COWW needs 2 to 4 weeks of aging to reach it's final hardness.

[williamwaco]

Maybe but not reliably. Answer for sure by pulling a seated bullet and measuring it.

[autopilotmp]

Thanks for the responses, I picked a Lyman M die and it works wonderfully. I am currently using air cooled coww+2%tin. After much reading I should probably be water dropping them, however I will test this first batch and let my rifle do the talking.