Can't seat primer deep enough, small bump

G

Gawp

New member
Hi,

I'm trying to make my first batch of .30-30 Win cartridges! I just received everything and after having measured the brass & bullets to make sure everything is right, my first step was to seat the primer.

I have a Lee Classic Turret Press and I use the priming system that comes with it to seat my primer (example in that video: https://www.youtube.com/watch?v=yLlYQ6wNjz4).

However, I just can't seat the primer deep enough into the primer pocket: when the primer is seated, there is still a very small bump under the cartridge (because the primer is not deep enough I believe).

When I put my primed cartridge on a flat surface (e.g. a table), it will wobble very slightly because of the bump caused by the primer. With manufactured cartridges or my unprimed cartridges, it doesn't wobble at all.

Below is a picture of a manufactured .30-30 Win I usually buy at the gun shop (bottom/left), and the brass I primed myself (top/right).

mXK2COe.jpg


I tried to push pretty hard on the press arm but it won't go any deeper.

What do you think is the problem? Is it because of the primer, the press...?

More importantly, is it safe like this?
 
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It is likely caused by the priming arm on the press not protruding far enough. If this is the case, no matter how hard you push it won't seat any further. Also, priming on press gives you way more leverage than needed. So the priming pin not protruding far enough would be my bet
 
On that note, is the primer arm sleeve screwed down tight ?
(If it has unscrewed a bit, it will leave the primer high)
 
It is likely caused by the priming arm on the press not protruding far enough. If this is the case, no matter how hard you push it won't seat any further. Also, priming on press gives you way more leverage than needed. So the priming pin not protruding far enough would be my bet
Click to expand...
It might be the reason indeed. I ordered another brand of primer, the same as the manufactured cartridges I believe (CCI LR primers). I'll see if it works better with these.

If it doesn't, I also ordered a hand priming tool (the Lee one). I'll see if it works with this one!

Finally, I also bought the Lyman Prep Case Kit with the tool to make sure the primer pocket is deep enough and make it deeper if needed.

l2.jpg


We'll know the truth soon!

On that note, is the primer arm sleeve screwed down tight ?
(If it has unscrewed a bit, it will leave the primer high)
Click to expand...
There is no screw for that tool. I tried to see what could be done to make it work better but... I don't see what could be wrong :/
 
Can you put a small round piece of masking tape on the priner seater and seat a primer in an empty case? The tape will have some compression, but it should be a good troubleshooting aid to verify if the seater is too short. If not thix, my bet is dirty or shallow pocket.
 
you can measure the primer and the cup depth with your set of calipers

http://bulletin.accurateshooter.com/...-and-accuracy/
Click to expand...
Hey, thank you hounddawg! I didn't know that trick!

So I did a few measurements (the measurements are in no particular order):

Case length => Primed case length:
51,67 => 51,83 => +0,16mm (0,006 in)
51,71 => 52,03 => +0,32mm (0,013 in)
51,67 => 51,76 => +0,09mm (0,004 in)
51,66 => 51,88 => +0,22mm (0,009 in)
avg 0,20mm (0,008 in)

Primer pocket depth:
3,35mm (0,132 in)
3,34mm (0,131 in)
3,33mm (0,131 in)
3,33mm (0,131 in)
avg 3,34 (0,131 in)

Primer thickness:
3,28mm (0,129 in)
3,26mm (0,128 in)
3,24mm (0,128 in)
3,24mm (0,128 in)
avg 3,26mm (0,128 in)

Conclusion: the primer pocket is deep enough, it is probably my priming tool which doesn't push the primer deep enough!


EDIT:
Can you put a small round piece of masking tape on the priner seater and seat a primer in an empty case? The tape will have some compression, but it should be a good troubleshooting aid to verify if the seater is too short. If not thix, my bet is dirty or shallow pocket.
Click to expand...

I will try it!
 
Push the priming arm sleeve down as far as it will go on the spring.
Is the top edge of the priming arm then fully exposed above the sleeve?

If not, there's your problem.
Solution (if that's the problem), file down the top edge of the sleeve so that the arm/edge is exposed above the sleeve.
 
what brand primers? i have used win, cci, nad rem. i have had some problems getting the remington to fully seat. no issues with win and cci. I would invest in a hand primer, much easier to use than the press and better feel for how the primer is seating.
 
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Take a good look at your press mounted priming system. There is something coming into contact with something that STOPS the system /limits the travel.

IF the stop portion and the primer seating punch are "off" a few thousandths in relation to each other, one way, your primers won't be seated correctly, no matter how much force you use. If they are "off" the other way, you can crush the primers in the pocket.

After using press mounted system for decades (and sometimes having the same problem you have) I switched to a hand tool, began with Lee, settled on RCBS.

Primers seat fully with just thumb pressure, and you can easily feel when they are seated.

I'd hold off on reaming the primer pockets, for now (especially with .commercial 30-30 brass). Primer pocket reaming is often a needed step with military cases, but rarely needed for US commercial brass. It's not impossible to "cut too much" and ruin the case. Not easy to screw up, but not impossible. ;)

Try priming using a good hand tool. My bet is that will solve the problem.

Be aware that some systems still come with two different punches for each primer size, one is flat the other is not (concave??) this is because ages ago, some primers were curved on the "top", and while they haven't been made like that in a long time, some priming systems still give you a punch for them.

Using the wrong punch for the primers you have will cause issues, as well.
 
Some shell holders if not properly sized/aligned might cause the case to lift or tilt under pressure. Me personally, as a rule I avoid doing anything to the primer pockets if I can help it unless I have to (like clean) because over time and repeated uses they gradually stretch and loosen their hold on primer.
 
Push the priming arm sleeve down as far as it will go on the spring.
Is the top edge of the priming arm then fully exposed above the sleeve?

If not, there's your problem.
Solution (if that's the problem), file down the top edge of the sleeve so that the arm/edge is exposed above the sleeve.
Click to expand...
I'm not sure how long is the priming arm so I'm not sure if it is fully exposed. But it goes above the sleeve for sure.

Lee??????
Click to expand...
Yes!

Make sure your bench is nice and solid, if it’s flexing that may be a problem.
Click to expand...
I think it is already.

what brand primers? i have used win, cci, nad rem. i have had some problems getting the remington to fully seat. no issues with win and cci. I would invest in a hand primer, much easier to use than the press and better feel for how the primer is seating.
Click to expand...
I'm using Winchester LR primers. I ordered the Lee hand priming tool, I can't wait!

Take a good look at your press mounted priming system. There is something coming into contact with something that STOPS the system /limits the travel.

[...]

I'd hold off on reaming the primer pockets, for now (especially with .commercial 30-30 brass).
Click to expand...
I can't figure out what it is... I'll just wait for my hand priming tool to be delivered I think.

There is one tool for reaming and another one, "Primer Pocket Uniformer", this is the one I wanted to try.

Some shell holders if not properly sized/aligned might cause the case to lift or tilt under pressure.
Click to expand...
I suspect it might be the cause as well... anyway I'm switching to a hand priming tool.

Thanks everyone, I'll tell you how it goes with the hand priming tool once I get it!
 
I have some news!

Make sure your bench is nice and solid, if it’s flexing that may be a problem.
Click to expand...
This man got it... it was indeed the problem! I made it so it's not flexing anymore (even if it was not a lot) and now the primer is seating correctly! I couldn't believe it at first but... it was the problem! Thank you so much jetinteriorguy!

I received my hand priming tool and my CCI primers as well, it all works great!
 
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