A Better Case Expander

View previous topic View next topic Go down

A Better Case Expander

Post by Dr.Don on Thu Jul 25, 2013 2:51 pm

I notice in many posts here the reference to "belling" the cases more or less to aid in bullet seating.  Many years ago I discovered what I think is a better method.  The idea is not original with me.  I took it from something I saw in a Lyman die set, and I think they called it an M-type expander.  Basically, instead of a tapered expander section which produces the familiar "bell" mouth, this expander used a stepped approach.  Most of the expander is the standard diameter needed to produce a tight bullet seat.  The stepped section produces a larger case diameter that is just right for a bullet to be inserted easily; and since it isn't tapered the bullet sits nice and square.  The step between the two sections is a 45 degree chamfer so the cases do not catch on the edge of the step. 

I use a Dillon 550 press and the expander is also the powder drop tube.  I am not aware of any special step type expanders available from Dillon so I made my own.  (A lathe is a nice tool for a guy interested in guns.)  I made them from tool steel and hardened them to resist wear.  I have a set for .45, 9mm, and .38.  In the picture below the bottom expander is the standard Dillon expander, and my homemade unit is above.  The detail shows the step, and the discoloration is from the heat treatment process.
Attachments
IMG_1356_4_1_1_1.JPG Homemade expander below, Dillon expander top.You don't have permission to download attachments.(70 Kb) Downloaded 10 times
IMG_1357_1_1.JPG Detail of the step expander.You don't have permission to download attachments.(69 Kb) Downloaded 10 times

Dr.Don

Posts : 346
Join date : 2012-10-31
Location : Cedar Park, TX

Back to top Go down

Re: A Better Case Expander

Post by urbanm84 on Thu Jul 25, 2013 4:06 pm

I also made a set awhile ago,but I welded up as needed and turned it back down in a surface grinder. I'll never use anything else again.
Mart

urbanm84

Posts : 24
Join date : 2012-12-30
Age : 60
Location : Comstock Park Michigan

Back to top Go down

Re: A Better Case Expander

Post by DavidR on Thu Jul 25, 2013 4:26 pm

Steve B. sells them on eBay along with other items he makes. I tried one in a 1050 and the cases would stick so I took it back out and returned it but he said they worked in his 550

DavidR
Admin

Posts : 2856
Join date : 2011-06-10
Age : 62
Location : NRA:Expert, Georgia

Back to top Go down

Re: A Better Case Expander

Post by Steve B on Thu Jul 25, 2013 7:45 pm

DavidR wrote:Steve B. sells them on eBay along with other items he makes. I tried one in a 1050 and the cases would stick so I took it back out and returned it but he said they worked in his 550

 I bought one of these for the 45 and it works real well.  I wish i could get one for every caliber.

Steve B

Posts : 333
Join date : 2011-06-16
Location : Elkhart, IN

Back to top Go down

Re: A Better Case Expander

Post by CR10X on Fri Jul 26, 2013 5:22 pm

I would also suggest considering making them wiht the rebated section between the expansion section and the bottem (that enters the case first).  This reduces the surface area and seems to make the extraction a little easier.  Dillon used to do this on the powder drop / expansion tubes, but apparently stopped this additional step quite a few years ago. 

Just a thought.

Cecil

CR10X

Posts : 356
Join date : 2011-06-17
Location : NC

Back to top Go down

Re: A Better Case Expander

Post by Sponsored content Today at 9:58 pm


Sponsored content


Back to top Go down

View previous topic View next topic Back to top


 
Permissions in this forum:
You cannot reply to topics in this forum