primer seating interfering with head space?

[West Calamus]

I have one particular rifle that bolt lock down is hard after sizing case and priming. Bolt locks down just fine after sizing only but once primed the bolt locks down hard and leaves circular scratch marks on primer where the primer would be mating up to the firing pin hole in the bolt face. If I go back and push primer down with a lot of force in a press then problem solved. Questions are: am I flatting the primer? Will switching brands of primer help? Do I have a tight headspace? Model 70 receiver and bolt , Winchester primers, Nosler and hornaday brass both and I clean pockets. No problems on any of my other reloads and rifles. Excuse me in advance for my ignorance.

 

[West Calamus]

I might add that the brass has been reloaded any where from 4 to 7or 8 times if that would make a difference and has always been somewhat of a issue on this rifle.

 

[Coldfinger]

Can you feel a burr on the boltface. A friend of mine had the same issue on a Browning FN action in 30-06. I couldn't see burr but could feel it with my fingernail. A gunsmith can't easily remedy the problem professionally. I put some diamond valve grinding compound on a case head in a drill and just lightly polished until the boltface was the same even color. I only did it this way due to the poor condition of the rifle and harsh environment it's exposed to, kinda like a framing hammer!!

 

[Lionel Boyd Johnson]

How do you clean your primer pockets? You can buy a carbide end-mill set into a disk to clean and uniform the depth of your primer pockets. Check with Sinclair's. I'll bet this would cure your problem. -Ed

 

[West Calamus]

Can you feel a burr on the boltface. A friend of mine had the same issue on a Browning FN action in 30-06. I couldn't see burr but could feel it with my fingernail. A gunsmith can't easily remedy the problem professionally. I put some diamond valve grinding compound on a case head in a drill and just lightly polished until the boltface was the same even color. I only did it this way due to the poor condition of the rifle and harsh environment it's exposed to, kinda like a framing hammer!!

doesn't appear nor can I feel a burr. Since the scratch marks on the primer is a 360 degree circle and with a bolt throw of 90 degrees I not sure this would be the cause.

 

[Mikecr]

I would have a gunsmith look at the bolt face and show him the primer marking.
Even if there was negative headspace, and primers seated proud of the case heads, the bolt face should not be marking primers like that.
It sounds like the firing pin hole is raised on the bolt face. Maybe always like that. Maybe it formed from past over pressure loads.

 

[Rardoin]

Either the primers are proud of the case head or you had a raised area on the boltface. If this is occurring in two different brands of brass then not likely a shallow punched primer pocket (I've seen this in one lot of .284 brass). Have you tried a different brand of primer? I found in RWS 6.5 x55 Swede brass with S&B primers I had to seat them with tremendous pressure to get them to be at proper depth. If you are not deforming the primer cup with the firm seating pressure you will not likely have any issues but consider trying a different primer if you have not done so.

 

[Jud96]

I would seat a primer like you normally do, then put the case head down against a square surface and move it back and forth easily and see if the primer is rubbing. If you can see shiny spots when the primer is rubbing than it's not seated deep enough. It could also be that your bolt face is cut like a crown and it's high in the middle and rubbing the primers or there's a burr on your bolt face or firing pin hole that's rubbing the primers.

 

[okie man]

Measure the case before priming and after. See if they are growing.

 

[West Calamus]

Thanks for the input guys. I put a straight edge across the case head that cycled and compared to ones that didn't. Yep, primers not being seated enough. I will step up the case prep work for sure. Again I appreciate the ideas put forth by members of this forum even if the answer is obvious it helps to eliminate possible reasons for the problem.

 

[West Calamus]

I might add that I think I will try a cci primer just to see if it seats deeper then the winchester primer.

 

[Niobium]

I find that the federal primers seat in nicely with no deformation of the primer cup, I use the rcbs hand priming tool and it gives a really nice handfeel to when the primer hits the bottom of the pocket. I had this problem once before in an older browning .270. Solved it by trying several primer brands and found federal to give me nice depth.

 

[okie man]

I don't load a case that doesn't have the primer pocket uniform and flash hole cleaned up. Good news is you're sized case seems to fit your chamber well!

 

[misterc01]

Might be worth a few minutes to uniform all the primer pockets so you know they are all at the proper size and depth. Another thought - not knowing how or if clean your primer pockets, but see if there is any crud that might interfere with seating.