Accuracy with Pulled Primers

[Catpop]

Engineer1911 has a thread on salvaging good primers from bad brass, others reloads, etc, etc.

Question: Has anyone actually tested salvaged primers against new primers under identical conditions. Same rifle, same day, same load, same bullet, etc.

I’m thinking none with offhand pistol plinking, they all go bang.
But rifle, whether range or hunting, is there a notable accuracy difference?
I’m very curious. Thanks

 

[edwardware]

Recognize that pocket uniforming, and seating primers to a specified force and depth (not "till it bottoms out") is normal technique in benchrest competition. Dispersion on target for pocket depth and primer seating force is in the tenths of MOA.

If you're not shooting half an MOA or better, you likely couldn't measure the difference.

My rifles and skills have me in the 0.5-1MOA range with several guns, and I know I couldn't tell.

 

[Walkalong]

In general shooting, I haven't seen any real difference in .308 "target" loads when using decapped Federal LR match primers. Load still shot .5 to .75ish at 100 yards. YMMV

I would have never done it in a Benchrest match, but Hall of Famer Alan Hall told me once, "If your primer goes bang, you don't have a problem".

I haven't tried it in my sub .5 PRS load, but haven't had any CCI-450 primers I have needed to decap and save. Bet it wouldn't matter enough to worry with.

But if it is in the back of your mind that it might or ill, don't do it.

 

[AK Hunter]

Of all the primers I have pulled or pushed out I don't use them for anything that needs to be accurate just plinking or test ammo.
Up to now they have all gone off.

 

[AJC1]

Would I compete for score with any component I did not have complete faith in, no. Would I load sighters and plinking rounds with recovered primers in these times absolutely.

 

[lightman]

I have never noticed any difference. But I don't load them in my hunting, competition or defense ammo. Just because............

 

[FROGO207]

I would think that they would be no different than the different brands and types of primers would show when used against each other. My shootimg would probably not notice anything different and have not in the past. Still would not use them for other than plinking or sighter ammo just because but will not make a difference I bet.

 

[Bfh_auto]

Recognize that pocket uniforming, and seating primers to a specified force and depth (not "till it bottoms out") is normal technique in benchrest competition. Dispersion on target for pocket depth and primer seating force is in the tenths of MOA.

If you're not shooting half an MOA or better, you likely couldn't measure the difference.

My rifles and skills have me in the 0.5-1MOA range with several guns, and I know I couldn't tell.

Same here. None of my rifles weight over 10 pounds. Also 90% of my shooting is field positions. I'm happy with 1- 1 1/4 minute like that.

 

[edwardware]

I would have never done it in a Benchrest match, but Hall of Famer Alan Hall told me once, "If your primer goes bang, you don't have a problem".

I have suspected that is the case, since if I was designing a priming system I would dimension the primer to completely saturate the mass of propellant. This would make the resulting pressure curve very insensitive to small primer variations.

 

[LiveLife]

Question: Has anyone actually tested salvaged primers against new primers under identical conditions. Same rifle, same day, same load, same bullet, etc.

But rifle, whether range or hunting, is there a notable accuracy difference?

Consider this.

New primers are shipped with anvil feet sticking out under the primer cup so anvil tip is not contacting the priming compound. This provides a safety measure in preventing detonation if box of primer is dropped (And why primers are further packaged in trays to separate primers individually) - https://www.thehighroad.org/index.p...s-90200-hand-held.871506/page-2#post-11567786

We "activate" new primers by seating them deep enough (.003"-.005" below flush on average) to push the anvil feet up into the cup so anvil tip will set against the priming compound so when firing pin/striker indents the cup, priming compound will detonate compressed against the anvil tip.

So "salvaged" primers are simply already "activated" primers. I have deprimed many primers from cases and when reseated into another case, they all went bang.

As to accuracy difference, consider this.

Primer detonation flash (Comparison of different brand primer flash documented here) involves flash size and duration but as well illustrated by pictures in the link, primer detonation flash extends well beyond any powder charge in the cartridge and I doubt if there would be any noticeable difference in the chamber pressure build and average max pressures achieved to propel bullet out the muzzle to produce muzzle velocity.

So as long as "salvaged" or "activated" primers are seated deep enough in the primer pocket to ensure the bottom of primer cup with anvil feet already pressed inside the cup contacts the bottom of primer pocket, I think we would see reliable primer detonation to ignite the powder charge, just like "new" primer that gets "activated" during initial seating.