Lapua tight primer pockets

Just purchased 100 Lapua .300 WM brass. Am having one heck of a time getting CCI 250 primers to seat all the way. Using a RCBS rockchucker press and have to really reef on it sometimes several times to get a primer to seat. Never had this happen with Lapua brass before. Anyone else have difficulty like this?
I've had that exact issue with their 223 brass seating Win primers.
 
if these are just very snug , they'll loosen up . if these are ridiculously tight , to the point of primer damage , send them back . I've been through the undersized primer pockets , with another brand of brass, it wasn't worth the fight .
 
I use a cheap Lee, press mounted priming tool, no problems seating any primer. Yes, on PPU brass. Lapua is always tight, sometimes after 10 cycles.
 
Just purchased 100 Lapua .300 WM brass. Am having one heck of a time getting CCI 250 primers to seat all the way. Using a RCBS rockchucker press and have to really reef on it sometimes several times to get a primer to seat. Never had this happen with Lapua brass before. Anyone else have difficulty like this?
I just reread your original post . if you're having problems priming with your press , send the brass back .
 
For precision-ish or better loading my opinion is I wouldn't prime on the press. The leverage is set up for case sizing, not priming and honestly not even for seating. Presses obviously work for priming and seating, but there are so many other tools that primer easier and/or better. The RCBS Universal hand primer is a great tool, comes with all the parts to seat large and small primers, turning tray is built into the unit. All around great value to move priming off the press, have used one for 10+ years and it's a quality tool:

Another option is to measure the pockets. You can order pin gauges through Grainger or McMaster Carr if you want to measure and track pockets over time, but a quicker/cheaper answer is a pocket swage gauge. If the go side doesn't fit they could probably stand a reaming (or send them back to Lapua). If the gauge fits just stick the primers in there for the first firing if they don't deform:

You could also try to ream out the pockets if they are too tight:
I like the 21st Century reamer because it's adjustable and you can set it short to only cut out of the top of the pocket and not hit the bottom, but the K+M has the virtue of no moving parts to adjust.



Continuing the PPU love 🤣 Monarch used PPU brass in their el-cheapo loads at one point (might still even). I have enough 30-30 brass to last several life times, and honestly the Monarch el-cheapo stuff didn't shoot any worse than the fancy Hornady Leverevolution - at least looking through buckhorns in my lever action.
 
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Having used at least a half dozen different Lapua cartridge brass, I've never had any dimensional issues with the primer pockets. I did have some issues a few years back with a lot of mFed GM small rifle primers being out of spec. CCI Small rifle primers worked fine in their place.

Several years ago I switched to the Forster Co-AX. I have found the hand helds(RCBS, Lyman, etc) did not provide the seating feel/leverage that I prefer, particularly with small rifle primers. Just me…
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I use RCBS bench priming tool to seat primers. I find that it is more positive and consistent than using my RCBS Rock Chucker press. Have you measured the pocket depth and diameter, also primer diameter and height? Have you compared measurements with other primer brands? You should not have to force primers into primer pocket. I have not used Lapua brass for any of my reloading so I cannot post on any experience. I am still have new in the box Remington brass I have had since the late 70's for 300 WM. What can I say I'm a reloading hoarder!
 
I have found the hand helds(RCBS, Lyman, etc) did not provide the seating feel/leverage that I prefer, particularly with small rifle primers. Just me…
I agree 100% about bench mounted being better than handheld. I can't run a handheld very long anymore in general, not sure I could get great consistency with one of the K+M or 21st Century, even with clicks or dials, because of my hands..... but I didn't want to mention the CPS again and start a riot 🤣 It's like saying try an AMP, a Sherman, a Hammer, or a Creedmoor!

I still use my handheld if I'm doing just a couple, but everything else gets run through a bench mounted primer.
 
Interesting...I have the exact opposite problem this week. Second firing on Federal brass 270 wsm, first time in 49 years reloading...25% 5 out of 20 brass primer pockets expanded and won't hold a primer! And Calvin...glue is too hold something together...it's not lube to help slide a tight primer in PAL. The thought crossed my mind...briefly...about gluing them in...lol With the way supplies are...shame to throw em away! Maybe I should freeze them, shrink the pocket....and only use them for winter hunting!😂
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I use RCBS bench priming tool to seat primers. I find that it is more positive and consistent than using my RCBS Rock Chucker press. Have you measured the pocket depth and diameter, also primer diameter and height? Have you compared measurements with other primer brands? You should not have to force primers into primer pocket. I have not used Lapua brass for any of my reloading so I cannot post on any experience. I am still have new in the box Remington brass I have had since the late 70's for 300 WM. What can I say I'm a reloading hoarder!
I have a Lyman case prep machine and tried reaming the primer pockets with it but didn't seem to change anything. Will see what happens when I fireform them.
 
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