Recent .357 Magnum primer seating issue.

[Crashbox]

I recently grabbed some virgin Starline .357 Magnum cases and began priming them with my Federal 200 small pistol magnum primers, using my dedicated RCBS bench-mounted priming tool. There were probably a good 10-15% of these which the primers would seat, but HARD. And I mean HARD. It was all I could do to get 'em seated without detonating them. I have never, EVER had issues in the past with this combo, and I have loaded thousands of them.

I was wondering if anyone else has had any recent issues with HARD primer seating, using Starline brass of late and/or Federal 200 SPM primers...?

Given the extreme demand for both items lately, it is entirely possible that one or both items have had some QC issues that I would classify as minor, in light of the times...

That's all. Thanks in advance.

 

[leprechaun50]

I use both Starline brass and Federal primers and have not had a problem with that combination.

 

[gamestalker]

I don't use Federal primers, but I load a lot of .357 starline brass using CCI 500's / 550's. I've never experienced anything even similar to what your describing though.

If they are as difficult to prime as you say, I wouldn't be using them until you've identified the culprit. First thing I would do is break out the dial caliper and do some measuring of both the pockets and the primers. Also inspect the pockets to see if there is some anomaly that's responsible for this. Maybe there is a bad spot in the pockets the result of a manufacturing die that got galled during production.

GS

 

[Crashbox]

I checked for pocket burrs, etc. on some of the toughies before priming and nothing unusual could be seen. I've seated primers in Sellier and Bellot brass and these are sometimes tougher yet. Reckon it's time for the dial calipers and the micrometer...

It is most puzzling as both Starline brass and Federal primers are high quality IMO. I know Federal gets hammered a lot for their seriously oversize packaging, but I just look at it as being a reminder of federal government-

 

[7mmb]

I know Federal gets hammered a lot for their seriously oversize packaging, but I just look at it as being a reminder of federal government-

That and a blown up UPS truck...

 

[leprechaun50]

I should also add that I have used CCI, Winchester, and remington primers in Starline brass without a problem.

 

[Crashbox]

I think I figured it out, it is a primer size issue. I grabbed some of my 'seasoned' .357 cases and sure enough, a few of them were very hard to seat.

Probably some new person in the plant and they thought magnum primers were somewhat larger physically, rather than a hotter primer compound

 

[cfullgraf]

Probably some new person in the plant and they thought magnum primers were somewhat larger physically, rather than a hotter primer compound

Probably some dies in the primer forming process that are at the end of their life and due to be replaced. It would not take much wear in the dies to make the primer hard to seat.

 

[Hondo 60]

That and a blown up UPS truck...

Every other primer mfg uses MUCH smaller packaging.
But then again Fed uses a more sensitive priming compound.

I'd be interested in seeing SAFE testing - to see if Federal really needs to use the larger packaging.
(don't wanna see or hear of a UPS driver gettin hurt)

 

[beatledog7]

There are some primers, such as Tula small rifle magnum, that are marginally oversized and thus hard to seat. That is the most likely problem.

I've never had a bad piece of Starline brass.

 

[Fishslayer]

Probably some new person in the plant and they thought magnum primers were somewhat larger physically, rather than a hotter primer compound

It was my understanding that magnum primers also used a slightly harder cup material? I know that seating standard CCI LPP in any headstamp requires really leaning on the lever to get them fully seated.

 

[Crashbox]

It was my understanding that magnum primers also used a slightly harder cup material? I know that seating standard CCI LPP in any headstamp requires really leaning on the lever to get them fully seated.

Perhaps so, but I've seated thousands of the Federal SP Magnum primers and this is the first time I've had this issue. I've got some CCI SPM primers in transit, it will be interesting how tough they may prove to be. I've loaded CCI regular SP primers before and they weren't all that bad...

 

[Steve C]

Over the years I have always felt that the Federal primers where a slightly bit larger in size than the primers of the other manufactures, esp with shotgun primers. Used to load using Win or CCI primers until the the pockets started to enlarge enough to make the primers noticeably easier to seat indicating the primers where starting to get loose. I would then switch to Federal primers for the next 4 to 5 loadings before disposing of the case which by that time had usually burned out.

New brass is almost always a bit tighter in the pocket but the variation is very slight. I've used the Lee primer pocket cleaner to make a turn into the pocket of new brass, even though it wasn't dirty, and found just the slight contact wear of the tool with the sides of the pocket have made it easier to insert primers. A dedicated primer pocket uniformer would probably be the correct tool if you wanted to invest in it to ensure easy primer insertion in new brass.