Federal 205mar primer not seating? Too big?

needham

Sergeant of the Hide
Hessian
Belligerents
Minuteman
Jan 24, 2020
132
44
I was loading up some load development rounds and ran into an issue with fed 205mar primers.
Up to 15% to 25% are getting destroyed while trying to get them to go in.

I ran this brass through a dillon 1050 to swage it.
When my dillon 550 would not seat the primer I bought a "swage it" for the 550 since I do not have the 1050 anymore.

Even using a rcbs hand tool they are often hard to seat.
Here is the kicker..... rem 7.5 primers seated pretty as you please????
Are fed205mar known to be slightly bigger?
I would highly prefer the 205mar work as I have many more of them than the rem7.5

What say you?
 
Last edited:

Mr Tibbs

Private
Minuteman
Aug 17, 2020
84
25
NeedHam : the Federal 205M have a thicker cup, the diameter for the Federal is .1744, the cup height is .1075
while the Remington 7.5 cup is.025, cup diameter is .1752, cup height is .110
 

needham

Sergeant of the Hide
Hessian
Belligerents
Minuteman
Jan 24, 2020
132
44
NeedHam : the Federal 205M have a thicker cup, the diameter for the Federal is .1744, the cup height is .1075
while the Remington 7.5 cup is.025, cup diameter is .1752, cup height is .110
Am I reading that right?
Because it seems like the 205 mar would go in easier?
 

FCS

Gunny Sergeant
Commercial Supporter
Belligerents
Minuteman
Jun 3, 2005
2,058
403
ABQ, NM
www.mccourtmunitionsllc.com
Needham- just out of curiosity, what is lot # for GM205MAR?


I’ve seen this when primer pocket and priming tool don’t line up. Primer starts crooked, cup catches edge of pocket and crumples giving you a FUBAR’ed primer.
Could be pocket isn’t concentric in case, could be misalignment between shellholder and primer carrier,
I learned if I ease into seating primer I could feel the problem cases and realign so primer would seat w/o damage but definitely slowed production rate.
 
  • Like
Reactions: needham

Average guy

Online Training Member
Belligerents
Minuteman
Online Training Access
  • Dec 25, 2018
    464
    304
    Try a regular deburring tool on the edge of the primer pockets. Sometimes a slight chamfer removes the sharp edge of the old crimp. Usually the ticket on brass with crimped primer pockets.
     

    needham

    Sergeant of the Hide
    Hessian
    Belligerents
    Minuteman
    Jan 24, 2020
    132
    44

    Seems more than plausible, thank you!

    Now how to keep it from happening?

    I measured both the 205mar and the rem7.5, both seem to measure .175, maybe the federal is a half to a full thousandth bigger.

    Just to be clear, the federals were also doing this on my dillion 550.
    With hand priming the federal would do it but the Remington would not.
     

    needham

    Sergeant of the Hide
    Hessian
    Belligerents
    Minuteman
    Jan 24, 2020
    132
    44
    Try a regular deburring tool on the edge of the primer pockets. Sometimes a slight chamfer removes the sharp edge of the old crimp. Usually the ticket on brass with crimped primer pockets.

    Yes unless figured out here, my next step is buying a lyman brass processor for the crimp removal attachment since it bevels it some.
    All I shoot is lake city.
    Bit after running this through a 1050 and a swage it tool, I have to believe the issue is with the primers not brass
     

    FCS

    Gunny Sergeant
    Commercial Supporter
    Belligerents
    Minuteman
    Jun 3, 2005
    2,058
    403
    ABQ, NM
    www.mccourtmunitionsllc.com
    If you feel primer going in with more force, stop, rotate case 180 or thereabouts and finish seating. Works majority of time but you really have to be paying attention.
    Slight bevel does help.

    I’ve had some issues with a different lot # of GM205MAR, same brass w/other primers are non issue. Something w/primer but haven’t found exact reason.
     
    • Like
    Reactions: needham

    needham

    Sergeant of the Hide
    Hessian
    Belligerents
    Minuteman
    Jan 24, 2020
    132
    44
    If you feel primer going in with more force, stop, rotate case 180 or thereabouts and finish seating.
    Yes indeed, I have done that many times and it works.

    Not that my feel is super refined, I have done that on tight primer pockets in the past so I know what you are talking about.

    However, with this issue it doesn't seem to help much, as before I feel the issue the primer is so wildly crooked or "rolled up" on the edge there is no saving it. Pretty much have to clamp down and force it to even get the case back out.

    I appreciate you advice and will definitely be feeling for it more intently
     

    Average guy

    Online Training Member
    Belligerents
    Minuteman
    Online Training Access
  • Dec 25, 2018
    464
    304
    Yes unless figured out here, my next step is buying a lyman brass processor for the crimp removal attachment since it bevels it some.
    All I shoot is lake city.
    Bit after running this through a 1050 and a swage it tool, I have to believe the issue is with the primers not brass
    It’s quick and worth a try.