Primer Cup Thickness
- Thread starter Joe
- Start date
G
GS Arizona
Guest
Wilbur, speaking only for myself, I'm endlessly fascinated by primers - small item, small mind.... 
Seriously, as a long-range shooter, primers are very important to load performance at 600 to 1000 yards, so I put a lot of energy into examining and testing them. In the world of competitive Benchrest, they seem to be less of a factor, so I can understand the relatively lower interest level.
German Salazar
Seriously, as a long-range shooter, primers are very important to load performance at 600 to 1000 yards, so I put a lot of energy into examining and testing them. In the world of competitive Benchrest, they seem to be less of a factor, so I can understand the relatively lower interest level.
German Salazar
Wilbur
Last winter I built 3 new rifles. Two for BR and one for hunting.
Actually, the hunting gun I have had for over 25 years and I rebarrelled it.
With the same old loads I have been using all along, I pierced a few dozen primers. (Yes, a few dozen)
This lead me on a crusade to find out why I was piercing primers.
After a couple of months of trials and tribulations, I decided to share my findings with my BR friends as I found it to be particularly interesting and informative.
Joe Cowan
Last winter I built 3 new rifles. Two for BR and one for hunting.
Actually, the hunting gun I have had for over 25 years and I rebarrelled it.
With the same old loads I have been using all along, I pierced a few dozen primers. (Yes, a few dozen)
This lead me on a crusade to find out why I was piercing primers.
After a couple of months of trials and tribulations, I decided to share my findings with my BR friends as I found it to be particularly interesting and informative.
Joe Cowan
Another thought about Primer thickness and hardness
I have had problems in the past while fireforming brass, getting the round to go off.
Especially when the shoulder is being blown out a good bit.
When relying on bullet seating depth for headspace, it is sometimes hard (at least for me) to get a good enough strike on a primer with a thick cup.
The info listed above will be considerable help in choosing a primer with a thin cup to get a sure fire the first time.
I have had problems in the past while fireforming brass, getting the round to go off.
Especially when the shoulder is being blown out a good bit.
When relying on bullet seating depth for headspace, it is sometimes hard (at least for me) to get a good enough strike on a primer with a thick cup.
The info listed above will be considerable help in choosing a primer with a thin cup to get a sure fire the first time.
Joe,
That specifically was one of the things I was testing. My findings were clear and unequivocal. You WILL NOT get the jammed bullet to hold the case back even with a thin cup.
And just getting the case to fire does NOT make for good brass.
Proper fireforming requires solid shoulder support.
sorry if it seems like I'm changing the subject this fireforming thing is one of my Hot Buttons.....
LOL
al
That specifically was one of the things I was testing. My findings were clear and unequivocal. You WILL NOT get the jammed bullet to hold the case back even with a thin cup.
And just getting the case to fire does NOT make for good brass.
Proper fireforming requires solid shoulder support.
sorry if it seems like I'm changing the subject
this fireforming thing is one of my Hot Buttons.....LOL
al
L
Larry Elliott
Guest
About ten years ago I was having trouble fireforming some AI cases using CCI 400 primers, with lots of failures to fire Although Winchester primers are supposed to be less sensitive than others, they gave 100% ignition with nothing else changed. Although the CCI 400's appear to have thinner cups they must be harder because they tend to not flatten and/or crater like WSR's or F205's.
About 15yrs ago I was big into shotgunning. I'd spent 10hrs on the patterning board and had worked up a great load using AA hulls and 700X powder (If I remember right). All was great, I used this load with success for some time, it came right out of the reloading manual and it patterned great, good vel etc.
One night I had to load up 500rds for our Thanksgiving Day shoot and I ran out of the Win primers.
No problemo, I had cases of others.......so I just grabbed a brick of federals and went to work.
Next day was cold, as we progressed into our shoot about an hour one of the guys started to get some odd sounding shots from his 870, he missed-whined-stuttered some birds-whined-got unmercifully scorned for his complaints------and all of a sudden had a hangfire that popped AFTER the action was open.
SPOOOOKY!!!
We stopped the action for an hour while we sorted it out. The buckets of rounds were cooling down from room temp......his was right by the corner of the building in the wind. Using his loaded rounds we all got hangfires and poopers.
The SAME LOADS but with Win primers were going on like gangbusters.
I set all of the Fed-primed loads back into the heated building and by carrying them in a pocket and using them warm we got thru the day. Later I burned them up for crow loads in the summer.
I called Federal all in a huff.
The technician that I talked to was a gentle and understanding soul......... he gave me a dissertation on reloading components and the use thereof. He explained how different powders had different ignition characteristics and different primers had different burn rates and brisance..... Even different chemical compositions, different actual priming compound mixtures. ALSO that priming mixes changes and evolved over the years, that it was a real pain when a problem was "cured" with a mixture but they couldn't publish because there were still old lots out there..........He furthermore stated that the loading manuals tested combinations through a wide range of conditions and also that they had characteristics charts that allowed them to spot problems and tailor primers to powders.......etc etc etc and ad nauseum, I was starting to feel flimflammed.
Me being a sneaky and belligerent unbeliever who was used to having snarky salespeople blow warm air up my skirts I asked him to read me from his list of "bad combinations".....
Combination #3 with a star by it was "Fed 209's lot numbers between XXX and XXX NOT compatible with 700X, ignition problems under 60 degrees, NOT recommended for any use"........
!!!!!!!!
KNOCked the pugnaciousness right outta' me.......
The guy then actually sent me 2000 primers for FREE!!! It's always left me with a soft spot for Federal products. I owe 'em.
My point is this:
I essentially ignore "burn rate charts" except to group powders near each other.
I ignore claims of "hotter" or "cooler" primers because I've had primers act "hotter" with one powder and then "cooler" with another. What I'm saying is, using 2 brands of primer and 2 brands of powder the trends may well REVERSE.
I start with stuff that's got a track record and NEVER change even so much as the primer without backing off a good bit and NEVER assume that a primer/powder combo will work until it's been run through the wringer of time and temp.
I guess when it comes to primer/powder combo's I just never assume.
I still remember the way my brother-in-laws safety glasses looked when he turned his soot-blackened face toward me and asked "NOW can I whine?"
al
One night I had to load up 500rds for our Thanksgiving Day shoot and I ran out of the Win primers.
No problemo, I had cases of others.......so I just grabbed a brick of federals and went to work.
Next day was cold, as we progressed into our shoot about an hour one of the guys started to get some odd sounding shots from his 870, he missed-whined-stuttered some birds-whined-got unmercifully scorned for his complaints------and all of a sudden had a hangfire that popped AFTER the action was open.
SPOOOOKY!!!
We stopped the action for an hour while we sorted it out. The buckets of rounds were cooling down from room temp......his was right by the corner of the building in the wind. Using his loaded rounds we all got hangfires and poopers.
The SAME LOADS but with Win primers were going on like gangbusters.
I set all of the Fed-primed loads back into the heated building and by carrying them in a pocket and using them warm we got thru the day. Later I burned them up for crow loads in the summer.
I called Federal all in a huff.
The technician that I talked to was a gentle and understanding soul......... he gave me a dissertation on reloading components and the use thereof. He explained how different powders had different ignition characteristics and different primers had different burn rates and brisance..... Even different chemical compositions, different actual priming compound mixtures. ALSO that priming mixes changes and evolved over the years, that it was a real pain when a problem was "cured" with a mixture but they couldn't publish because there were still old lots out there..........He furthermore stated that the loading manuals tested combinations through a wide range of conditions and also that they had characteristics charts that allowed them to spot problems and tailor primers to powders.......etc etc etc and ad nauseum, I was starting to feel flimflammed.
Me being a sneaky and belligerent unbeliever who was used to having snarky salespeople blow warm air up my skirts I asked him to read me from his list of "bad combinations".....
Combination #3 with a star by it was "Fed 209's lot numbers between XXX and XXX NOT compatible with 700X, ignition problems under 60 degrees, NOT recommended for any use"........
!!!!!!!!
KNOCked the pugnaciousness right outta' me.......
The guy then actually sent me 2000 primers for FREE!!! It's always left me with a soft spot for Federal products. I owe 'em.
My point is this:
I essentially ignore "burn rate charts" except to group powders near each other.
I ignore claims of "hotter" or "cooler" primers because I've had primers act "hotter" with one powder and then "cooler" with another. What I'm saying is, using 2 brands of primer and 2 brands of powder the trends may well REVERSE.
I start with stuff that's got a track record and NEVER change even so much as the primer without backing off a good bit and NEVER assume that a primer/powder combo will work until it's been run through the wringer of time and temp.
I guess when it comes to primer/powder combo's I just never assume.
I still remember the way my brother-in-laws safety glasses looked when he turned his soot-blackened face toward me and asked "NOW can I whine?"
al