Tight fitting primers

[Minky]

Recently I've noticed that in once-fired cartridges some of the primers (all OEM primers) are in very tight primer pockets. No rust, just tight primer pockets. Forcing the primers out with one downstroke results in a slight bulge ring around the primer pocket or bowing of the cartridge base.  Now, when I experience a tight primer, I back off the operating handle of my size master and rotate the case half a turn, and bring the handle down again. Some really stuck primers require rotating the hull several times before it will drop out. With this approach, I've found that most of the tight primers can be removed without distorting the hull'cases base and the amount of bulge, if any, is far less than just forcing the primer out with one stroke. It mainly sems to be high brass.  I've measured different  cases and every dimension I  can. The collet has been checked for debris and well coated with copper slip. Strangely when the primers are shifted out a little bit they can easily be popped out with the tip of a screwdriver. Anyone got any ideas as to why.?

Edited November 12, 2021 by Minky

[aberisle]

What primers and what cases are you using 209 primers are not all the same size

[Minky]

I can understand that if I couldn't  get a new one in but it's  trying to get the factory one out that causing the problems.  I'll  get a vernier micrometer and measure one that is tight and others.  Then I'll measure some different new ones. Thanks  All good ideas and things to look at.

Edit. 28 gauge cases.  Various makes, Bournaghi, Eley high brass seem the worst.  Primers from different factory once fired seem to be pretty consistent in diameter at 0.243"  and the new ones (Winchester) are again ( 0.243" ) the new ones slides into the primer pocket quite happily with an interference drag.  When I've extracted the spent primer the deprime bar and spike go through the case and primer pocket hole quite easily.  It's almost as if the old primers have been sealed into the pocket with some sort of glue/varnish with such a grip that the bases can get bowed out.

Edited November 12, 2021 by Minky

[aberisle]

could the primers be "sealed" to make the shell weatherproof with lacquer or something...what cases are they?

[Minky]

I was editing my post and missed that one.  Nothing really visible as to sealing.  I'll  make more measurments and observations.   It's  not the end of the world to loose a few cases and when the primer is out they reload well. It's just as to why its happening and what's causing it.

[Gas seal]

Hi Minky are the primers knocked out before the collet starts to resize the brass . Maybe the punch is not central to the primer making it hard to push the primer out it could be loose.  Is it working ok with short brass cases. I use the MEC JR  mark 5  28gauge and a 12gauge they have a a resize ring. I also use MEC steelmaster 10gauge with a seizing collet they all work fine resizing. The photo of primer size may help. The only case I had trouble with was cleaver 28gauge, the new primer I used Cheddite were loose.

[Minky]

Thanks for the image of the primer sizes. Later today I will look again with more care of the diameters and check the timing of the punch but overall some cases are fine and others aren't and it's  only getting some out that three is a problem. 

[harkom]

Is the tip of the de-priming rod straight with no deformation of the tip. Sounds like there could be a mal-alignment of the tip and the primer that you are expelling.

[mellors]

12 hours ago, Minky said:

Recently I've noticed that in once-fired cartridges some of the primers (all OEM primers) are in very tight primer pockets. No rust, just tight primer pockets. Forcing the primers out with one downstroke results in a slight bulge ring around the primer pocket or bowing of the cartridge base.  Now, when I experience a tight primer, I back off the operating handle of my size master and rotate the case half a turn, and bring the handle down again. Some really stuck primers require rotating the hull several times before it will drop out. With this approach, I've found that most of the tight primers can be removed without distorting the hull'cases base and the amount of bulge, if any, is far less than just forcing the primer out with one stroke. It mainly sems to be high brass.  I've measured different  cases and every dimension I  can. The collet has been checked for debris and well coated with copper slip. Strangely when the primers are shifted out a little bit they can easily be popped out with the tip of a screwdriver. Anyone got any ideas as to why.?

I've had the same problem with fiocchi 16 mm head cases. As said i think it's possibly the primer removal rod not locating or tipping when pulled down. I also have had no problem with the 8 mm head cases perhaps they move enough to accommodate the location of the rod as it comes down. 

[Minky]

Right. I've spent a lot of time on this problem today.  I've checked and measured loads of things and arrived at a solution. I accurately measured  all sorts of types / makes of ejected primers. Most are  "0.243 overall but when rotated they vary by a thou or so.  I operated the unit with no case.  No fault found here.  I got a strong light and checked the collet area to see if there was a rogue  pellet stuck in there causing jam up and that it was all lubed up.  All clear. checked to see if there was a build up of spent primers under the ejection port of the collet. all ok.  So then I cut a couple of cases down so that I could see what was happening down at the primer.  This did result in where / what the problem was.  The primer punch isn't low enough to pop the primer out before the collet unit closes up thus you're  trying to over force close the unit.?  The punch is more than long enough and the main amount of punch is halfway up the case tube. Now I don't quite know why this has suddenly become a problem because it isn't damaged or worn and it has been performing well.  To get over this issue I removed the primer punch rod and fitted 2x2mm thick washers on the top thread stem below the top plate. this means that the punch pop's the primer out before the collet locks up.  The primers pop out easily.  I measured the case heads  before and after the colet resized them and this was ok.  The only slight difference to the operation was that I  wasn't almost bending the handle and breaking the machine although the operation was done before bottoming the stroke out.  Job done. ps. By cutting a case down you can see exactly that the case is located in the right place and the primer punch is dead central. I hope this is simple to understand and easy to do.  I still dont understand why it is necessary though. I'll  put some pictures  up later. 

[Gas seal]

It sounds like you were sizing the case before the old primer was knocked out. When l started to reload I used hand tools to de prime and size the case . If I didn’t size the cases sometimes the new primer would be loose. Are you using a MEC machine, there website shows how to set each station up.

[Minky]

1 hour ago, Gas seal said:

It sounds like you were sizing the case before the old primer was knocked out. When l started to reload I used hand tools to de prime and size the case . If I didn’t size the cases sometimes the new primer would be loose. Are you using a MEC machine, there website shows how to set each station up.

Q  It sounds like you were sizing the case before the old primer was knocked out.

Yes this is exactly the fault on this machine.  I'm not depriming or repriming on separate tools. The machine is a Mec SizeMaster SM82 in 28 gauge. I misunderstood your question there.

Q website shows how to set each station up.

The thing is that there is no setting up on this operation.   You put the case in the collet  and then pull the handle. There isn't any alteration of adjustment. On this machine nothing has been changed/ modified, altered or damaged so not sure why this is doing this but the two washers have cured the problem... and why mainly on high brass.?  The internal case dimensions are practically  the same on high and low brass..?

Second edit. ... if you've sworn at it.. beaten it... and all else fails get the instruction manual out and read it.!!!

I moved the loader and took some pictures.... after I'd finished and put the camera away I noticed that round the back underneath the collet there is a locknut.??  Also the main central shaft that has a peg and roller that controls the collet linkage.  All of this was pretty dry.  Now I've  got to find the manual and all the other paperwork.  Or read it online. The saga continues tomorrow. 

Edited November 13, 2021 by Minky

[Gas seal]

Hi Minky if you loosen the lock nut you can adjust the collet by turning anti clockwise to (widen the collet) and the handle will lower. The de prime punch should then be lower as the handle will be lower and remove the old primer. Hope this helps. I will look for the instructions for the machine I will still have them somewhere.

[Minky]

A few pictures of the unit and the mod that I've found to work.  I don't know how the pictures will view because I have had to resize them down from about 14 meg per image.  I cut a few scrap cases down so that I could see what was happening down at the primer end.  1 The collet is open and the short case is sitting down on the base ring.  2 you can see that the collet is nearly closed but the primer punch is still way up the case, probably near the top of the original case length.  3. The punch with the two added washers.  4 The punch being fitted into the top plate.  5 The punch in place with the 2x2mm washers fitted.  in this configuration the primers are popped out and the base is resized down to the same size as a std new round.

Edited November 14, 2021 by Minky

[Minky]

I'll mow investigate the locknut setting under the bottom plat on the collect stem and see what that does.  I did look at the manual and this is covered but the details are are a bit thin.

Edited November 14, 2021 by Minky

[Minky]

After loads of reading and checking I have found the reason for this fault and how to resolve it.  I found that the locknut on the bottom of the collet stem which is located under the back of the base had come loose.  I found that the collet must have rotated during loading and had changed its adjustment.  By fluke I turned the collet fingers and the whole finger unit threaded up and down. I had fitted two washers on the primer punch stem so I removed these washers and tightened the punch stem nut up.  I put a high brass into the collet and adjusted the fingers so that I had full stroke and the primer was popped out before the collet locked up then tightened up the locknut underneath.  This gives an answer to the fact that it did work ok and then wouldn't pop the primers out before the collet locked up.