Most sensitive Large Rifle primer?

[someguy2800]

I tried some older CCI 250 magnum primers that I found at a local gun shop today. Firing pin indents are shallower than they were with the Winchesters indicating harder or thicker cups but the priming compound seamed to be more sensitive. 3 of the 15 failed to fire and interestingly striking them again would not light them like it would with the Winchesters. I am going to try to get to Cabelas in the next couple weeks to pick up some S&B primers and in the mean time I'm going to take it apart again to see if I can slick it up some more internally or find if there is something catching that I can't see externally.

 

[Load Master]

I was thinking of trying the S&B after reading about the issue with them being too thin for 308 pressure. That should be about perfect since a 444 is about 10K psi lower than a 308.

Federal was my first thought but I haven't seen any federal rifle primers in years

Here is a little more data on primers that might be of use. I'm still doing some testing, but the S&B are the thinnest cut I've measured so far.

 

[1stmarine]

any change you can share some close ups of the primers both the ones that ignited and the ones that didn't ?
In an empty case what is the average depth fo the pocket and then the average length of the primer?
I am thinking something else can be happening and the systems is simple enough to be fixed like increasing the pin protrusion but
first need to discard other factors.
Also the firing pin overall length might be a factor vs.simply the protrusion.

 

[someguy2800]

I just checked the loaded rounds I have on hand and the primers are seated between flush and about .004" below flush. I always seat primers all the way to the bottom of the pockets with a good shove on the press arm.

Here are the CCI magnum primers I shot today. As you can see the indents are very shallow. The tall one sticking up is one that did not fire and was only struck once.



Here are the winchesters. Some were struck once and others 2 or 3 times. You can tell the cups are softer or thinner than the CCI's but not necessarily more sensitive.



I took everything apart tonight and fiddles with it awhile. The first thing I did was go find the original hammer spring out of the drawer. After holding the original and the new one next too each other I noticed that the new one seams to have relaxed quite a bit. I believe the temper is not quite right. I put a little bit of extra bend in the original and put it back in.



Secondly I hate to even talk about this on the internet because someone will surely tell me I don't know what I'm doing and have ruined everything but I made some modifications internally. I noticed while playing with it that the sear catches on the hammer a pretty good way forward from the fully retracted position of the hammer, which gave me the idea that I should get more hammer force if it was using the full available stroke of the hammer. So I took it apart and tig welded up the old sear location on the hammer, reshaped it a bit and cut a new sear. I have always thought the trigger is to far back in this gun so while I was at it I changed the geometry a bit to bring the trigger forward slightly and take some of the mechanical advantage of the hammer spring off the sear. Once I had the angles right I stoned them and got the sear engagement the way I wanted it and adjusted the pull using the trigger return spring. I got it about where I want it at a very crisp 4lbs. Moving the trigger position messed up the transfer bar so then I had to weld some material on the nose of the lever that holds the transfer bar in place while the hammer drops. After taking it apart about 20 times I got it perfect. The transfer bar engages 100% when pulling the trigger with your finger, but does not engage if you leverage on the trigger with a stick with no follow through. Just the way it should be. So now the sear catches on the hammer about an 3/16th of an inch or so from the fully retracted position so it should have some more stroke. I gave everything else a good once over and checked that the firing pin is free and not binding in any way and nothing is catching on the hammer.

 

[someguy2800]

Here is a little more data on primers that might be of use. I'm still doing some testing, but the S&B are the thinnest cut I've measured so far.

Good to know. I think those S&B might be just the thing since the 444 marlin runs at only slightly more than 44 magnum pressures. S&B lists there large pistol primer at .5mm cup thickness and there large rifles at .63 and .7 for the two different types. I can't believe they sell those primers with no warning on the box about pressure limits.

 

[1stmarine]

It seems you are mechanically oriented that is a good thing and these mechanisms are simple enough to make some diy improvements.
Just a reminder any trigger parts must be properly heat treated as you probably already know.
the one that has been striken once and didn't ignite seems seated a bit deeper and perhaps shallower protrusion from the pin?
But it could be the picture. Initially I don't see anything crazy but I would see if I can induce a more aggresive strike and perhaps try a spare firing pin if you can.
It is good to have a spare anyway right? The protrusion doesn't have to be round and uniform but must be blunt. Remember how strikes are printed from a glock
that are known for very reliable strike wiht all sort of ammo from all over the world.
I am not saying it has to be that way and or shape but the consistency in the strike is what you need. Of course that they are well seated an not too deep
consistently.
I think the spreads from the primer pocket depths might tell you that.
You have probably though about this but one thing we can be certain, unless primers are bad they should ignite with enough protrusion and speed no matter
what firearm. I don't believe a softer primer is the answer to the problem. It can help but might not cure it.
I hope this makes sense.

 

[Salmoneye]

I've seen cartridges that headspace on the rim do this when the rims are too thin for a particular gun...

Try different brass, and/or a box of factory loads...

For me, changing the internals on the gun would be the last step to making it fire reliably...

 

[fguffey]

Again: I was home minding my business when I got a phone call from a firing range; they wanted to know what was wrong with R-P ammo, I told them the phone number was on the box; so? Call Remington. That after noon 20 R-P rounds show up. 15 fired and 5 that failed to fire. The 5 that failed to fire had attempts by 4 shooters to fire in 4 different rifles. There was nothing suspect about the big dent in the primers, all of the primers in the fired cases were small and all confirmed to the firing pin and the spring managed to hold the pressure.

To shorten the story we pulled down the failed to fire rounds and measured and weighed, magnificent ammo, we then installed the primers back into the came cases they were removed from; I chambered the cases with primers into one of my M1917s (with killer firing pins) and proceeded to bust the primers one after the other. The shooter with the problem had a New Ruger rifle with 2 boxes of new ammo.. It was a waste of time because no one got the shooters name and phone number and they did not bring the new box with Remington information.

The fired and failed to fire cases fit my gages, including home made chamber gages, there was .001" difference in length between the shoulder and case head between the failed to fire and fired cases, And then there was the Miracle, the failed to fire cases did not shorten when I busted the primers, for those that can keep up the primers were hit at least 6 times, The last hit had to be the toughest hit of all because? I have killer firing pins.

F. Guffey

 

[1stmarine]

hard to say there is no difference but at least not a substantial one.
It is not to simply to "put a dent" on a primer and more "how" that happens.
The speed of the strike and cases must be fully supported both consistently.
Assuming there are not issues with the brass and pocket depth in the first place.
This can happen too but it is either an entire batch or very rare.
All those things measurable anyway.

 

[1stmarine]

Once you strike it once and fail to ignite the next strikes have less chances to ignite on average
as the primer is already deformed and primer compound broken out of place.
If the cases are not properly supported then that is a problem and also easily measurable.

 

[fguffey]

hard to say there is no difference but at least not a substantial one.

Again and something else to ignore; I have an Eddystone with a chamber that is .016" longer than a minimum length/full length sized case from the shoulder to the bolt face. :"Hard to say..." meaning the chamber is .002" longer than a field reject length gage. When I fire 30/06 ammo in that rifle that is full length sized the case does not stretch between the case head and case body. And then there is something else no one understands the shoulder on my cases do not move when fired in that rifle. I do not find it amazing but that rifle was made that way. To cut down on all that clearance I form cases for that chamber from 280 Remington cases; how can I miss?

 

[fguffey]

Once you strike it once and fail to ignite the next strikes have less chances to ignite on average
as the primer is already deformed and primer compound broken out of place.
If the cases are not properly supported then that is a problem and also easily measurable.

The 5 failed to fire cases had been hit at least 5 times in 4 deferent rifles. after the 5 attempts at firing I I busted the primers on the 6th attempt (after removing and inspecting the primers for all that deformity, and broken pieces, and then there was the anvil). Properly supported? Again, I am the one that only wants air between my case and chamber, I do not want a lot of air so I size cases to fit/; I understand that is confusing but when I start with a case there is a big chance the case will not allow the bolt to close when I start. The art and science of sizing is to know when to stop reducing the length of the case from the shoulder to the case head.

One of the most accurate rifles I own has a short hook up meaning to bust a primer the firing pin has to get into a hurry in a very short distance to bust the primer, I know, I know, I can change that but I would not risk giving up the accuracy for adding time and distance to turn the rifle into another rifle with a killer firing pin. I paid $120.00 for the rifle and then I paid more than that for the mount rings and scope.

F. Guffey

 

[someguy2800]

Guys I'm going to define where the goal post is. When I pull the trigger it needs to make a bang noise and a bullet needs to come out the end of the barrel. I don't care if I find the source of the problem or simply a workaround because the result is the same. I can either make the hammer deliver more energy to the primer, or I can find a primer that requires less energy to fire. I've checked the gun and cases extensively and can find nothing wrong, you can choose to believe me or not. The cause of the problem is most likely the original hammer spring was just tired and the replacement spring I put in appears to be incorrectly tempered as I showed on the last page. I believe I've done everything I can do on the gun side of the equation so we will see if that gets it through the goal posts later today. If not the primer is next. I don't care if factory ammo works in it or not. I'm going to make the parts I have and the cases I have work.

 

[1stmarine]

The 5 failed to fire cases had been hit at least 5 times in 4 deferent rifles. after the 5 attempts at firing I I busted the primers on the 6th attempt (after removing and inspecting the primers for all that deformity, and broken pieces, and then there was the anvil). Properly supported? Again, I am the one that only wants air between my case and chamber, I do not want a lot of air so I size cases to fit/; I understand that is confusing but when I start with a case there is a big chance the case will not allow the bolt to close when I start. The art and science of sizing is to know when to stop reducing the length of the case from the shoulder to the case head.

One of the most accurate rifles I own has a short hook up meaning to bust a primer the firing pin has to get into a hurry in a very short distance to bust the primer, I know, I know, I can change that but I would not risk giving up the accuracy for adding time and distance to turn the rifle into another rifle with a killer firing pin. I paid $120.00 for the rifle and then I paid more than that for the mount rings and scope.

F. Guffey

If one wants to make the best possible fit one has two options: Neck size only and at least FL but make it so slightly to be snug in that chamber.
Some folks suggest the case SAAMI gauges but the only true reference is the chamber itself. So one might want to start with fire formed brass
or otherwise take the bolt extractor and with everything very clean find the best possible fit to close reliable.
BR shooters ask precision builders to headspace after their custom loads with the actual brass and not the gauges.
If one has a flexible headspace like provided with adjustable nut then that might be something one does this way between seaons.
Most people do not need to do this but what I am saying the starting point is to know ones chamber.
Because a rifle says 223R on the side gives only a very limited amount of information about the chamber. Like on this one there are at least 12 different reamers
a maker might be chambering with most of them backwards compatible with the 223.
As always the most critical meausure to start with is the headspace from the datum of the shoulder to the base of a clean chamber and case.
In the case of the op is the actual rim. and because of the straight wall there is no backup plan like lets say a 300 win mag. (virtual 2nd headspace)
The thing with trouble shooting remotely via thread is very hard because even with great pictures there are so many things we cannot see and feel.
But I would say calipers and micrometers are the best way to assure we do not assume anything. And we should not assume anything.

 

[someguy2800]

Update:

I went on vacation with the family to Yellowstone two weeks ago but the night before we left I worked on the gun some more but it still did not ignite the primer on 2 of 10 rounds.

While on our way west we went past the Cabalas in Billings Montana so I stopped in and picked up a brick of S&B large rifle primers. Got home last Saturday but didn't get a chance to load or shoot any ammo before having to leave on a trip for work on Sunday. I did however try loading 10 of them in empty cases and firing them. All of the primers fired. I got home from my work trip yesterday and this morning I loaded 10 rounds and fired them. All 10 rounds fired and were accurate on target at 100 yards. I did notice afterward that two of the primers appeared to have slightly smaller indents than the others. I also had two rounds hit on the paper slightly lower than the other rounds so I will need to do some more shooting and chronograph testing to see if there is a correlation between the two. For now though the gun goes bang when you tell it to and is quite accurate so its a step in the right direction at least.

 

[ArchAngelCD]

IMO that gun should still take a trip to a good gunsmith and get a complete check up because it still sounds like a gun problem, not a primer brand problem. It's very rare a rifle won't ignite a primer, especially a single shot rifle.

I'm glad the S&B primers fire but the problem still remains. Searching out primers that will fire is only a cover-up.

 

[someguy2800]

I know its a gun problem but I'm content with a primer solution.

 

[Reloadron]

I have a 444 marlin Handi Rifle that I worked over to make a nice accurate deer rifle. Only issue is that it has occasional light primer strikes. I put in a wolff extra power hammer spring in it but it is much much worse with that in. I put it in a month or more ago and never test fired it until today. I shot 20 rounds in it today and I think there were only 1 or 2 that went off with one hit of the hammer.

General consensus is Federal are the most sensitive but with what you have with only one or two primers detonating out of twenty I would guess you have a real problem in that trying a more sensitive primer will not make the rifle reliable. Primers, all primers are made to detonate within a given set of parameters and not detonate outside those parameters. All rifle firing systems are designed to detonate any primer made to standard specifications. You can certainly try other primers but with the odds you mention I would not be very optimistic. You have replaced springs, you can look at firing pin protrusion.

I just want to know if there is a large rifle primer that is easier to ignite than a Winchester.

Then in a word the answer is yes. Try Federal and if you can't find Federal try Remington. Keep in mind that primer sensitivity can vary within a lot by any manufacturer on any given day.

Ron

 

[ArchAngelCD]

I know its a gun problem but I'm content with a primer solution.

OK then... It looks like you found the primers that will help you. I hope they continue to perform 100%.

 

[someguy2800]

Just wanted to update this. I have shot about 100 rounds through the gun prior to deer season to get confidence in its reliability and its been 100% reliable with S&B primers and the new factory hammer spring. I accidentally loaded some earlier this week with winchester primers and the 2nd shot missfired. I pulled them and replaced with S&B and its been shooting great and the accuracy is very good. I shot a small buck with it this morning.

 

[Walkalong]

Excellent!

 

[Slamfire]

Just wanted to update this. I have shot about 100 rounds through the gun prior to deer season to get confidence in its reliability and its been 100% reliable with S&B primers and the new factory hammer spring. I accidentally loaded some earlier this week with winchester primers and the 2nd shot missfired. I pulled them and replaced with S&B and its been shooting great and the accuracy is very good. I shot a small buck with it this morning.

Well good hunting and thank you for the update. I had no idea that S&B primers were that sensitive and it is good information to know.

Buy all the current lot of S&B primers you can, for manufacturer's can change the product at any time and change the product characteristics at any time. An example is Winchester. The nickel plated WSR was a great primer, I used tens of thousands in my AR's. Then, Winchester made them "more sensitive" in 1999. The brass WSR pierce and ate up so many firing pins that I have never bought another. There is no law that S&B can't change the product and make all their primers less sensitive, and then you would be back with an unreliable rifle.

 

[someguy2800]

Yep, I have 900 left and will pick up another 1000 next time I'm at cabelas. I wrote 444 marlin handi rifle on the box and will keep it just for that. I'm also going to buy a couple more hammer springs while they are still available to put in the parts drawer. That should more than satisfy my 444 needs for the rest of my hopefully 60 years on this earth. The grand kids can figure it out after that.

 

[Load Master]

As far as Sellier & Bellot changing, I guess that is possible but they have been the most consistent primers I've used for may years with the lowest standard deviations compared to other brands, even the CCI BR primers.