Jump to content
Brian Enos's Forums... Maku mozo!

Inconsistent neck expansion with Lyman M Die


surgdog

Recommended Posts

I have been prepping 223 range brass picked up at matches and have my Dillon 650 set up with a "loading" tool head consisting of partial resizing/decapping in station 1, Dillon RT1200 station 3 and Lyman M die station 5.

I have noticed a significant number of cases have the mouth flared too much so that they don't pass the chamber check. I find myself having to reset the M die a fair bit.

 

I suspect the problem is range brass being different lengths and some go further into the die than others causing the extra flaring.

Has anyone dealt with this in reloading and should I just not use the M Die for range brass. It sure makes the bullet go in easier when is works correctly.

Any suggestions would be appreciated.

 

Thanks,

M Koury

Link to comment
Share on other sites

I have had some of this but it was due to the die working loose. All cases should be the same max length after coming out of the trimmer so make sure you have set the "M" die up for the max length and check it for tightness every few hundred rounds


Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

 

21 minutes ago, Hi-Power Jack said:

Are you trimming the brass before loading?

Yes, as stated the RT 1200 trim/size die is in station 3 BEFORE the M die.

 

18 minutes ago, Tmcfarland said:

I have had some of this but it was due to the die working loose. All cases should be the same max length after coming out of the trimmer so make sure you have set the "M" die up for the max length and check it for tightness every few hundred rounds


Sent from my iPhone using Tapatalk

The trimmer has a maximum length of around 1.747 or so (I can't get 1.750 to save my soul due to trimmer moving a bit when turned on). That is the length I set the M die for. A good number of cases are shorter so never get trimmed. Interestingly, I did find the M die mandril stuck in a case I guess from slowly unscrewing with use. Thinking about putting some locktie on it.

 

Another thought I had about this since posting is to get rid of M die and have mouth expansion with a PowderFunnel in the powder die. That has worked very good with pistol rounds.

 

What do y'all think about that?

Link to comment
Share on other sites

I think I identified the problem. I pulled the inner portion of the M die out and found the mandril had come partially unscrewed again which of course over flares some cases over time. Put some blue locktite on it and ran about 300 cases. So far so good.

 

Edited by surgdog
addition
Link to comment
Share on other sites

  • 2 weeks later...

Your problem is that your setting up your trimmer so that it's not trimming all cases.  You want to set up your trimmer for the short side 1.750 or the trim to length, not the long side.  If you did find that your shortest cases are 1.752, then you could set up your die for that as well.  You will get some variation in OAL because you are using range pick up brass.  It happens.  You should also have set up your sizing die so that it's sizing all the cases not just some.  

Link to comment
Share on other sites

  • 1 month later...
On 4/10/2017 at 6:25 PM, surgdog said:

I think I identified the problem. I pulled the inner portion of the M die out and found the mandril had come partially unscrewed again which of course over flares some cases over time. Put some blue locktite on it and ran about 300 cases. So far so good.

 

My M-die is doing the same. I'll have to take a look at mine and see if that's cause. 

Link to comment
Share on other sites

On 4/10/2017 at 8:25 PM, surgdog said:

I think I identified the problem. I pulled the inner portion of the M die out and found the mandril had come partially unscrewed again which of course over flares some cases over time. Put some blue locktite on it and ran about 300 cases. So far so good.

 

 

I have had this issue as well.  I clean all my M-dies and actually have super glued the mandrel on each one.  This pretty much makes it impossible for them to come apart.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...