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FLATTENED PRIMERS FOR 223 LOADS

6K views 52 replies 16 participants last post by  FreedomAndForgiven 
#1 ·
I have loaded several test batches for my AR 16" barrel with carbine length gas tube . get flat primers from the first shot. I am using once fired FC brass that I deprimed before tumbling with walnut which came out clean as new. Resized using Lee die bumping the shoulder a bit to get good feed and seat. Tumbled again to remove lube. Trimmed using Lee case length gage on a Lee cutter on a Lyman Case Prep Express and deburred as well as deburred the flash hole with the Lyman tool. Primed with CCI Small Rifle Primers using Lee Ram Prime on Lee handpress. Bullet used is Hornady 55 grain FMJ BT with cannalure set at the bottom of the cannalure and a little more than a light crimp. Bullets are not geting any setback from recoil, I checked. Loaded using Hornady 9th for .223 and 55 grain FMJ data starting at minimum to maximum 5 rounds with .3 grain increments. All charges were weighed using a Frankford Arsenal 750 digital scale with fresh batteries and watching for drift. I have used CFE223, BLC-2, H335 and IMR 3031 powders. The brass ejects the pretty much the same as factory federal 55 grain 223 with the exception of the flat primers, case web looks no different to me.
I guess my question is could the flattened primers be due to I am using standard small rifle primers verses the #41's and just need to pay attention to the case web for pressure ring or could I have bumped the shoulders to much reducing case volume increasing pressure (i have eyeballed one of mine to a factory unfired case and to me they dont look to different. I did mess one up by smaching the shoulder in the process)
 
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#2 ·
Probably got the shoulders pushed back too far. But being a "gas gun", you have to work a little closer. Shoulders pushed back too far, round goes BANG, primer gets pushed out of it's pocket a little then pushed back in by the firing pin. See if your fired brass will fit back in the chamber and the bolt closes all the way into battery. If so, size the necks and reload but remember. you're working real close because of it being a "gas gun". Next time, full length resize but be careful not to push the shoulders back as far. About .002 is good.;)
 
#3 ·
Ok. I just dropped a spent case in the chamber and dropped the bolt. It went into battery but extraction took a bit of a pull on the charging handle, but not so much that I believe would effect operation. Only one way to find out, guess I need to get the neck sizing die on order as I only have the 3 die set for .223, all my other sets are 4 die.
Nor Cal Mikie thanks for that bit of information. I had wondered if your suggestion was possible but just was not sure if it was safe so I did not even try it or mention it and look like a DA if not a good idea. But I guess it is a bit late as I have already made the DA mistake of setting the shoulder back a tad to much. Now to not do it again.
 
#5 ·
I guess first thing to do will be to measure to the shoulder using a factory unfired brass, one of my sized brass and one of my fired test load brass to see what the differences are and go from there? Maybe get some #41 primers and see how they do with my resized brass?
I have 2000 pieces of brass and like 4500 bullets have made 100 test loads and made no progress.
 
#29 ·
That is a good question. Especially since they can look different than a standard rifle buffer which most of us have. What about counting the coils of the spring since rifle and carbine springs shouldn't be interchanged? I don't have your understanding of the components, but have read enough to know lots of strange to dangerous things can occur w/ wrong mix.
 
#7 ·
Got a photo of the flat primer's? CCI, as I understand it, have a softer cup and primer's can look flat but aren't really a problem. Are you sure the tug you feel taking out a round is not caused by the bullet entering the lands a bit? If the bullet is touching the lands, it can raise pressure.
 
#8 · (Edited)
A flattened primmer is not out of the ordinary even for factory ammo. Its when the spent primmer has a rim that is extruded on the primers back end is a sure singe of over pressure. I mean that it will have a sharp edge or rivet like appearance.

Measuring case web expansion will only work if your measuring a first time fired case and compare that to a unfired case from the same batch as a comparison. But keep in mind that brass cartridge cases can vary in the brass hardness. Brass is 70% Copper, 30% Zinc , and .0.07% Lead. These %'s varied as much as .01% will will produce brass that is ether a little soft or little hard. Also most of the brass used now a days is recycled. This can add more variability. So one should work up a load for a particular firearm starting with a batch of new brass if possible. I mite add that a blade type micrometer is the best tool to measure case head expansion.

Also for a shell shucking gun/auto loader, you should use a Small Base sizing die. RCBS offers them. I have them for .223 Rem., .308 Win., and 30-06 Spfl.

The only problem with S.B. sizing dies, is that they can work harden the brass by compressing down the case in front of the web after multiple resizing. This over time could lead to case head separation. This can some times show up as a bright ring that will have a roughness that can be felt by dragging a razor blade across it. Or use a 10 power lope to inspect the bright ring to see if it looks fractured. Another more simple tool one can make is to take paper clip straightened and sharpen at one end to a point and then bend about 1/8 inch that end 90 degrees. Then insert the hooked end into the case mouth down to the web and drag it up along the inside of the case and if the web is going separate one can feel it dip or catch into brass where it will separate.

A case Head Space Gauge is also a good accessory for determining how much if any that one is pushing the case shoulder back during the resizing process. Midway sells one made by L.E. Wilson for $25.00. I again have one for every cartridge I load for when I need produce ammo of SAAMI spec.. I use a 0.000 - 1.000 inch depth micrometer to determine this. If the case extends beyond the base of the gage, I set the base of the depth micrometers base on the case head and run the spindle down to the gauges base. This will show how much set back has accrued to the case. Then move the sizing die down into the press a little bit, and resize the case again. Do this until the case is flush with the head space gauge. I also will remove the decapping pin with its sizing button so as not to stretch the case neck from working that one case over and over again. When correct head space is achieved, reinstall the decapping ping assembly and size a 2-3 case and check them in the gauge. Also to remember to relube the case if you do this operation to the one case every time you run the case into the sizing die so as not to have to deal with as stuck case in the die.

I do not claim to be the definitive ammo loading expert, but loading/reloading ammo for of forty years has tought me a lot of good information that has allowed me to craft ammo that will test the accuracy of every gun I have owned.
 
#10 ·
Interesting. I've never
A flattened primmer is not out of the ordinary even for factory ammo. Its when the spent primmer has a rim that is extruded on the primers back end is a sure singe of over pressure. I mean that it will have a sharp edge or rivet like appearance.

Measuring case web expansion will only work if your measuring a first time fired case and compare that to a unfired case from the same batch as a comparison. But keep in mind that brass cartridge cases can vary in the brass hardness. Brass is 70% Copper, 30% Zinc , and .0.07% Lead. These %'s varied as much as .01% will will produce brass that is ether a little soft or little hard. Also most of the brass used now a days is recycled. This can add more variability. So one should work up a load for a particular firearm starting with a batch of new brass if possible. I mite add that a blade type micrometer is the best tool to measure case head expansion.

Also for a shell shucking gun/auto loader, you should use a Small Base sizing die. RCBS offers them. I have them for .223 Rem., .308 Win., and 30-06 Spfl.

The only problem with S.B. sizing dies, is that they can work harden the brass by compressing down the case in front of the web after multiple resizing. This over time could lead to case head separation. This can some times show up as a bright ring that will have a roughness that can be felt by dragging a razor blade across it. Or use a 10 power lope to inspect the bright ring to see if it looks fractured. Another more simple tool one can make is to take paper clip straightened and sharpen at one end to a point and then bend about 1/8 inch that end 90 degrees. Then insert the hooked end into the case mouth down to the web and drag it up along the inside of the case and if the web is going separate one can feel it dip or catch into brass where it will separate.

A case Head Space Gauge is also a good accessory for determining how much if any that one is pushing the case shoulder back during the resizing process. Midway sells one made by L.E. Wilson for $25.00. I again have one for every cartridge I load for when I need produce ammo of SAAMI spec.. I use a 0.000 - 1.000 inch depth micrometer to determine this. If the case extends beyond the base of the gage, I set the base of the depth micrometers base on the case head and run the spindle down to the gauges base. This will show how much set back has accrued to the case. Then move the sizing die down into the press a little bit, and resize the case again. Do this until the case is flush with the head space gauge. I also will remove the decapping pin with its sizing button so as not to stretch the case neck from working that one case over and over again. When correct head space is achieved, reinstall the decapping ping assembly and size a 2-3 case and check them in the gauge. Also to remember to relube the case if you do this operation to the one case every time you run the case into the sizing die so as not to have to deal with as stuck case in the die.

I do not claim to be the definitive ammo loading expert, but loading/reloading ammo for of forty years has thought me a lot of good information that has allowed me to craft ammo that will test the accuracy of every gun I have owned.
I have never loaded for but one rifle that wasn't a bolt, Rem 760 years ago. I've never used a small base dies and had no idea they could do to a case about the same as excessive head space can do. Is it possible to partial re-size them or would the case head then keep the case from seating in the chamber right?
 
#9 ·
Looking at primers isn't going to tell you much of anything about pressure. Well, unless it's blown smooth out of the primer pocket. Then you have an over pressure round for sure.

Save yourself the headache and guess work and get yourself a chronograph and a box of factory ammo that has the velocity listed so you know how much less velocity to expect from a short barrel.
 
#13 ·
This.
I too was getting flattened primers on my Colt LE6920 even at moderate powder ranges so I bought a chrono for $49. It assured me that my loads are just fine and it's highly unlikely I am running a dangerous PSI based on velocity I was getting from the chrono.
PSI can be tested with a number of methods, the most common current one being a carefully calibrated piezoelectric transducer affixed to the chamber. But unless you're super anal retentive, it's not worth buying one.
 
#16 ·
Hodgdon for example, lists pressure and velocity with their online data. So, if you're working up a load and reach their velocity there's a very good chance that you're at or exceeding their listed pressure. With variations in lots of powder you could, A) reach their velocity below their listed max. B) not reach their velocity at listed max.
Unless you're a velocity chaser there's really not much need to get to a max load since the optimum charge weight for accuracy usually falls below maximum.
 
#15 ·
You don't measure pressure with a chrono.
Just velocity. In THEORY, if you're exceeding velocity for a given powder and bullet weight you *might* be in an overpressure situation.
But the cheaper chrono's are sometimes off, I had a nice spread going on some 30-06 rounds last weekend until one bullet measured 6,599 fps. :eek: Obviously the snow flakes coming down were messing with the sensors or I wouldn't be alive to type this.
 
#17 ·
Two things: I think way too many people chase ultra high velocity rather than accuracy and reliability, and the other is that science may be against me on this - but flattened primers are a worry to me. I'm still thick-headed enough to be convinced that flattened primers are telling me that my pressures are getting too high.

In all of the years that I've been hand loading, there has only been (for me) ONE instance where my ammunition has benefitted by a heavy charge, and that was my .30-06 with IMR-4350 and the old Speer 180 grain SPBT. That load was right at the maximum charge in my old Lyman manual and gave something like 2885 FPS - according to that manual. I load for accuracy and function, and none of my other loads are maximum charges. Most often the best loads have been mid-range in charges.
 
#18 ·
Wow, I really did not expect I would get this kind of response to my question but it will all help me and maybe someone else in the future.
In response to an earlier post about maybe my C.O.A.L. being to long - My overall length was 2.230 and the rounds feed and extracted fine when I tested the first 5 thru the gun by using the charging handle. The tug was to remove a spent case dropped into the chamber as suggested in the first post. I could be wrong but wouldnt a 55 grain bullett to hit the lands be to long to fit the mag and barely be in the case mouth? (agree semi-auto brass needs FL resize, please forgive my DOH moment)
I am not chasing velocity, I am looking for the load that gives me consistent MOA or better when I do my part behind the rifle. The velocity will be what it is when I borrow a friends Magentospeed.
I know there are differences in hardness of primers between the makers and even the types, ie. CCI Small Rifle verses CCI #41. But just wanted to see if issue with flatened primers is or is not something to worry about as I did not use the #41's which Big Mac seems to have covered. Guess I really need to get my hands on the headspace gage to know when to stop bumping the shoulder and make a few more to chrono.
Have tried to get a pic of the primers but having trouble getting a quality pic to do any good. I will try for a beter result this evening.
 
#19 ·
I think for you, you'll be better off just full length resizing. And make sure you don't push the shoulders back too far.;) After you've done it for a while, only then can you try other ways of sizing your brass. Keeps you out of trouble that way.:D

There was issues about neck sizing M1A brass. Only full length resize!! If not, you'll poke your eye out.:eek::rolleyes: Tried sizing just the neck to see if it could be done. Worked like a champ but not recommended for the every day reloaded. Good way to get your butt in a crack.:eek: Been reloading for a few years so it was something I "just had to try".:)
 
#20 ·
I load my .223 rounds for the AR's with 26grs of BLC-2 using either 41's or CCI magnum primers. The 41's you load using magnum data so essentially the same. The magnum primers also help minimize the cold weather sensitivity that BLC-2 has. I run OAL at 2.23 and a light crimp with the Lee FCD on the 55gr boattail bullets, but no crimp on flat base 55 or heavier bullets. I don't see any flattening of the primers other than normal, it's when they spread out and completely fill the primer pocket that you are having problems.

If you get a chance, grab some IMR 8208XBR and load some of the 55gr Hornady's up with 25.4-25.5 grs at that OAL, my favorite and most accurate load out of all the 16" carbine AR's that I've built...well, except one that had a 1:7 twist, it liked the BLC-2 load a lot better!
 
#21 ·
Speaking of primers, and apologize for going slightly off topic, but I wanted to show firing pin strike differences between copper primers on 1883--1887 copper cartridges vs modern primers (CCI Magnum Lg Rifle) Case in point a model 1873 Trapdoor. (Cartouche is 1883 so it had the 1879 improvements)

Same rifle struck all of these cartridges. I was fortunate enough to have some original casings that came with my trapdoor.

You'll notice the same "slightly" offcenter strike but most noticeable is how the soft copper primers 'rose' around the edges when fired back 137 years ago. Naturally these were the corrosive primers mated with the inferior copper cartridges that the Army began transitioning to brass.

Some say that Custer lost because of known 'copper fouling' in the chamber when the rifle heated up. I believe that MAY have played a part in the defeat but overall numbers and piss poor planning was the primary reason,,,,but that's a whole 'another topic!

Copper Ammunition Metal

Ammunition Button Brass Metal Bullet
 
#22 · (Edited)
Twicepop;
The only reason that I spoke of small base dies is that with any shell shucker/auto loading gun, is it will give the most reliability when the gun is cycling.

The problem with auto loading guns like the AR 15, is during the chamber reaming step of the barrel machining processes, is that the gauging of head space is usually done with one test bolt that in all likely hood, that bolt will not follow that barrel to the finished gun unless one is to order a AR 15 custom built. I know this as a fact as that for 6 1/2 years I worked for a company that manufactured AR 15 uppers.
 
#24 ·
I like your logic, but I disagree with the use of small base dies - UNLESS - the rifle will not cycle ammo reloaded with standard full length dies. In it's simplest terms, sizing with small base dies over works the brass an unnecessary amount. I am certain that there are plenty of rifles out there that do require small base sizer dies, but I haven't come across one yet myself. The semi-autos I load for are (3) AR-15, (2) M1 Carbine, Russian SKS, Norinco MAK90, M1A and M1 Garand. None of those require small base sizer dies. At least mine don't.
 
#23 ·
Mogunner;
Have you tried Western Powder/Ram Shot, TAC powder. I used it for a AR 16" HBAR in .223 Rem.
26.4 gr., TAC
Std. Win., small rifle
53 gr., XFB, Barnes-X,Triple Shock
DNL brass
Roll crimp
Texas wild pig eradication load.
Not able to chronograph them though because a fiend, oops, I mean friend shot my chronograph. A safe load in my gun.
 
#27 ·
I'd love to try Ramshot, heck, I'll try and work up a load in any powder pretty much, but I'm severely limited in what I can find hereabouts. I have a couple suppliers about 40 miles south of me but their prices are about $5 per pound higher than they ought to be, but it's 100 miles the other direction back to where I used to buy my supplies prior to moving out here to the boonies. I have the wife stop in there when she's up every month for her doctor's visit, but she's clueless when I start talking about what powders to check for, the best we've managed is she goes into Dunn's Sporting Goods and texts me photos of the powder shelves...lol
 
#25 · (Edited)
Twicepop;
I'm more of a bolt gun fan, so most of the time for my rifles I only neck size. With that said its really a conundrum for me to have use a small base sizing die because accuracy/reliability is always a compromise with auto loaders.

I have tried using a standered sizing die for .223 ammo for AR's with some success, but only if the guns chamber is a little over sized. That happens when the chamber reamer starts getting dull and the barrel maker is only checking for head space.

The AR company I used to work for first supply of barrels were made as a rifled blank from one company, and then sent to another company to do the turning work including the chambering. It was not a good arrangement. With my suggestion of trying another barrel maker who worked the barrel from a blank bar to a finished barrel worked out much much better.

The other side of the coin, is when a chamber reamer is resharpened to many times it will produce a under sized chamber. This was not a problem for the company I worked for because the reamers were acquired from Clymer who would tell use that the reamer was at the end of its life being that it could not make a minimum SAAMI spec chamber any more. As a side note. Instead they can be sharpened and used to make a sizing die reamer which the company I worked for had quit a lot of. I used one of those reamers to make my own neck sizing die that utilizes the Redding neck sizing bushings and it works great.

The problem with AR's, is there are so many company's now making bolts, barrel extensions, and some god awful barrel makers out there supplying the builders of AR's, that it is all about tolerances, or tolerance stacking.

So in the end its like with Stradivarius violins, every one is a little different.

This has really gotten off the original subject.
 
#30 ·
Although I may end up getting some grief over this here goes, because when you are asking for assistance you aint gonna get it without full disclosure sometimes. As stated I ran my test loads thru a 16" barrel (1:7 twist 223 wyld) by Black Forest Outfitters with carbine length gas tube. I bought everything for this 16" upper at a gunshow 3 days before the election. I used the lower off of my 18" DD Stainless (1:7 twist 556) rifle length gas tube gun as I only have the one lower at this time, wanting to get an 80% lower. The lower is Aero Precision with Aero Precision buffer kit (APRH100151) with carbine buffer (buffer knowledge is lacking) with a CMG 3.5# single stage drop in trigger. My first group of test loads (hornady 55 gr. FMJBT w/ can. Data from Horn.9th OAL 2.230 using cfe223 at start) were fired using the 18" upper and I got flattened primers as well. When I shot my last group of test loads using same bullet and data source using BLC-2, H335 and IMR -3031 I used the 16" upper because it was on the lower and got flat primers again, using CCI SMALL RIFLE PRIMERS. But when I have shot factory Federal 55 grain ammo using either upper on the same lower the primers look better.
 
#31 ·
Have you only fired minimum charges? If so add more powder. Shoot the loads over a chronograph and see how your velocities compare to the manual. That's the only way you're going to know if you're pressures are ok. Unless you want to buy a pressure trace II.
The world would be so much easier if the old wives tale of flattened primers meant high pressure would disappear. Primers and primer cups are not created equally. Some are softer, some are harder. Looking at the primer isn't going to tell you one bit about pressure, unless they're blown out of the primer pocket.
 
#32 ·
Well I don't completely buy that. A primer completely flattened in the pocket with the cup right up against the hole in the case indicates to me, way to much pressure. You remove one of them and put a new primer in and you'll notice it goe in very esy. Had a guy back east tell me when that happens to him, he simply glues in a new primer. I cannot recommend that. Another sign on the primer is gas leaking around the edges, it's turn the edge black. By the time you reach this point, either point, your gonna be way over pressure. If your to the point where the primer is flattened all the way to the edges, Your likely going to have a bolt sticking too. If your running hot loads, over time your gonna notice a cut forming around your firing pin hole on the bolt, it's called flame cutting, gas coming out around the primer does that. There has been a time or two in my past that I could not reach a max listed load what I'd call safely, and I do push! There also are time's when I have gone past the max listed load but I've never gone more than a grain. One exception to that is with my 6.5x55. In my Hornady book it is listed that the test arm used was a 96 Mauser. It's not able to handle the pressure of my Mod 70 so I do exceed it. To cross reference it I used the Nosler data for the cartridge, tested with a Lilja barrel and I think a universal receiver. The data vary's quite a bit and the Hornady bullet is a bit heavier so I start low and work up to 1 gr over max, one round at each 1/2 gr increment, to watch for pressure. I have not found max in most cartridge's but seldom reload over max load listed in a modern fire arm. Nosler notes that their 6.5x55 data is intended for modern rifles in good condition and warns against using it in older military Mauser's. if your rifle will get to max without pressure sign's, it's great place to stop!
 
#35 ·
There's a big difference between a primer that fills the pocket and a primer that enlarges a pocket. I agree that if a primer is enlarging a pocket you have a high pressure situation. Getting a primer that fills the pocket from minimum to maximum tells you absolutely nothing.

I too have gone above book max in some cartridges. As much as 3 grains without issue. I've also put so much 4895 in an 8x57 case that a bullet could barely be seated. Do I recommend someone that doesn't know what they're doing to do that? Definitely not.
 
#34 ·
Slayer - thats a no on just minimum charge. I started at minimum and went to max in .3 grain increments. I do have one correction though, my test charges were in groups 3 and not 5 as I believe I stated earlier.

Don Fisher - please, what is it that you do not buy. I am asking to learn because I do not want to blow up a gun. I looked at my spent cases and could not see any evidence of gasses escaping around the primers. My bolt is new, black nitride coated and used for approximately 125 rounds 75 being my test rounds. I can see a little ring around the firing pin where the outside edge of the primer is contacting upon firing but does not seem to be any different from firing factory ammo. Ammunition Bullet
Auto part
 
#36 ·
There's a big difference between a primer that fills the pocket and a primer that enlarges a pocket. I agree that if a primer is enlarging a pocket you have a high pressure situation. Getting a primer that fills the pocket from minimum to maximum tells you absolutely nothing.

I too have gone above book max in some cartridges. As much as 3 grains without issue. I've also put so much 4895 in an 8x57 case that a bullet could barely be seated. Do I recommend someone that doesn't know what they're doing to do that? Definitely not.
If the primers are filling the pocket from minimum to maximum, that doesn't seem like a pressure issue to me. I have a 308 Norma mag that does the same thing. I chronograph my loads and that told me that I'm not having any issues with pressure. Since you've already gone minimum to maximum with that powder, load 3 at minimum and 3 at maximum and shoot them over a chronograph and see how they compare to what the manual says.
 
#37 ·
I too have gone above book max in some cartridges. As much as 3 grains without issue. I've also put so much 4895 in an 8x57 case that a bullet could barely be seated. Do I recommend someone that doesn't know what they're doing to do that? Definitely not.
I wouldn't recommend someone who does know what they are doing to do that, because they should know better.
 
#38 · (Edited)
Ok. Not gonna worry so much about the primers as there seems to be no gases getting by them and the flattened section only measures .003 to .005, but will try some #41's as soon as I can. Will clean up some of the cases in my pic to try them again making sure to check primer pocket for change in size and how a new primer seats. Will also get a headspace gage to measure cases while FL resizing making sure no more than .002 shoulder bump and checking seating and extraction. Then fire new rounds checking MV compared to some factory ammo.

BTW, Thank you all for the wisdom shared to vanquish some ignorance. I salute you sirs.
 
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