Home Forums Hunting & Shooting Ask The Gunwriters Small rifle v Small rifle bench rest primers

700's are notorious for this, though you see it in other makes as well. Excessive clearance around the pin tip allows primer cup material to flow into the area between the pin tip and the hole. This 'shears' the material, resulting in a hole in the primer cup. Technically, it's a 'blanked' primer. A true 'pierced' primer is something different.

Regardless, the fix is straight forward and has been done for decades. The pin tip diameter is normally reduced/recontoured. You might be able to band-aid it with a different primer but sooner or later, it will bite you.

If you've had this happen, remove the fp assy and get all the little bits of material from inside the bolt body.

Good shootin' -Al

Gre-Tan bushing the boltface is the answer with the 700. They've done a couple for me.

Don’t know if GreTan is taking on work, but if so have him bush the bolt. Simple fix and he does great work.

Maybe I've missed it, but when we're discussing small rifle primers and pierced/blanked/magnum/ball powder ignition/etc, some attention should be given the CCI #41.

Those are decent too. Not a whole lot different from 450s, practically speaking.

Why spend money bushing FP holes, etc when you can just change primers? Speaking from an AR15 perspective here. 450s are never a problem.

Primers
I found this page if it helps.

That's good to know, John.

There were a few sources online which showed the 205 M had a thicker cup than the standard 205, but none of them were the primer manufacturer.

In my experience, the 205 M has a "tougher" cup than CCI 400's. I have a bolt gun that does pierce primers, a Ruger American in 223. I started substituting CCI 400's in loads that produced pierced primers with 205 M primers after looking at chart on James Calhoon's website, and the piercings went away. The site showed that 205's and 400's had the same cup thickness, but that the 205 M primers had a slightly thicker cup. My experience bore that out, but I made a faulty assumption about standard 205's based upon someone else's measurements.

The primer piercing issue went away when I quit using 400's in that rifle. I consider it more a feature than a flaw in that gun.

Great conversation. Thanks for the chart LBP. I certainly hope should America ever get back to "normal" we can pick and choose the primers of our choice. I like the Federal 205M's. Less cratering and a bit more accuracy. I'm willing to pay a bit more for them. Just my observations.

kwg

Butch,

I was told about the primer compound being spread more consistently in match primers while touring the Federal plant in 1996--which was also when they told me the brass used in each match-primer manufacturing lot was also the same--not another batch of brass received later.

But one other thing learned from interviewing the folks at various manufacturing plants over the decades is that many companies tweak their products now and then--how often depending on the product and "perceived need." One example is the history of how CCI 450 primers have changed over the years....

Sounds like an interesting story, John, I'd love to read it.

says one not caring about accuracy in their ammo often then. Its often that a primer change makes a pretty fair difference in groups. Blind statements like this show ignorance.

I watched a gun show some years ago that said basically what Swift52 said. This was at the CCI plant. The most experienced people who could spread the compound the best and most even were those who made the Bench Rest primers. They were not hotter than the others just more consistent. I don't know if they are worth the extra $70 unless a person had a rifle that could prove it.

Actually your statement shows blind ignorance as MD said the same thing in this thread. Or are you saying MD’s statements are blind ignorance also.

Federals have proven themselves over the years so that's what I start with, no matter the application.

As far as the Benchrest versus Standard primers thing, it isn't something to get to hung up on as long as you're using an appropriate primer for the application.

One of my competition rifles (30BR), the Fed 205M, standard 205 and the Winchester WSR all perform the same. Several others (two .22s and a 6mm) show a marked preference for primer series (Benchrest versus Standard) but not brand.

Every once in a while, I'll work with a rifle that really shows a marked difference with primers....they tend to be factory rifles with large primer cases. But in general, unless things are wonky and not making sense early on, I save any primer testing to the end of load work.

Good shootin' -Al

Al,

Saving primer testing until the primary load work is also what I do--AFTER I've determined which bullet, powder and seating depth work best.

Might also mention that have been playing with my 6mm PPC benchrest rifle for about a decade now, not for competition but just to see what stuff can make a difference. One of my tests involved trying some European primers obtained during the LAST primer shortage, when the standard American brands were unavailable. Turned out that Sellier & Bellot small-rifle primers out-grouped the typical American brands, including CCI BR4s and Federal 205Ms.

Had purchased 1000 each of S&B small and large-rifle primers. After the testing (which included the LR primers) I tried to purchase more, but the company where I bought 'em was sold out.....

John

John, seems like we both approach load work the same way.

Some years back, an engineer pal that worked for one of the major ammo and bullet companies sent me some large rifle primers to evaluate. At that time, I was shooting a shortened 308W-based cartridge using the Lapua 308 case in Hunter Bench Rest class.

Anyway, the primers were pretty strange. They had a slippery gray coating on the cup (almost like a sealer), the priming compound was bright green they had a black anvil. They shot crazy good...every bit as well as the 210Ms I'd tested extensively. My suspicion is they were RUAG or Swiss sourced. When I sent my results to him, he said the "agreement" with the primer company fell though.

Weird, for sure.

Stay warm out there! -Al