Issue with primer pockets on new brass

[Thegeek]

I bought 500rd of .300BLK new American Eagle brass. I primed three cases and the primer is visibly higher than the face of the case head. I thought my hand priming tool (RCBS) just wasn't pushing them in far enough. I decided to push the three I did the rest of the way in with my press. No go. I decided to measure. The primer pocket on the brass is 0.018" deep. The CCI 400 small rifle primers are .020" tall.

I'm going to load and fire 2 round to see if it slam fires. I'm not really comfortable with this outcome. Has anyone else come across something like this?

 

[BiscuitsandGravy]

No. Not good.

Think about it, the bolt closes, the firing pin is still traveling on its way to that primer which is now .002 closer. I'll pass.

Did you try to see if the bolt will close properly by hand with the primer sticking out?

EDIT: Now that I've measured some SR's... S&B .117", CCI 400 .118", Rem 7 1/2 .122", Tul .117".

Some more reference....
Primers And Pressure

https://www.thehighroad.org/index.p...-a-primer-a-primer.319275/page-2#post-3936874

I would exercise caution.

 

[bgcatty]

Send them back. No reason to take chances, safety first when it comes to reloading. Period!

 

[BiscuitsandGravy]

Send them back. No reason to take chances, safety first when it comes to reloading. Period!

Call them up and get them replaced if they are all like that. A bad production batch and bad QC.

 

[Old Syko]

I bought 500rd of .300BLK new American Eagle brass. I primed three cases and the primer is visibly higher than the face of the case head. I thought my hand priming tool (RCBS) just wasn't pushing them in far enough. I decided to push the three I did the rest of the way in with my press. No go. I decided to measure. The primer pocket on the brass is 0.018" deep. The CCI 400 small rifle primers are .020" tall.

I'm going to load and fire 2 round to see if it slam fires. I'm not really comfortable with this outcome. Has anyone else come across something like this?

Your dimensions don't make sense.
MINIMUM AND MAXIMUM DIMENSIONS OF PRIMER POCKETS
Here is a table of the minimum and maximum primer pocket and primer dimensions. Surprisingly this data isn't too easy to find, so I have done the research for you. Dimensions in inches.

Pocket Type	Depth Min	Depth Max	Diameter Min	Diameter Max
Small Rifle/Pistol	0.1170	0.1230	0.1730	0.1745
Large Rifle	0.1250	0.1320	0.2085	0.2100
Large Pistol	0.1170	0.1230	0.2085	0.2100

Primer pocket dimensions and tolerances

Primer Type	Height Min	Height Max	Diameter Min	Diameter Max
Small Rifle/Pistol	0.1150	0.1260	0.1745	0.1765
Large Rifle	0.1230	0.1360	0.2105	0.2130
Large Pistol	0.1150	0.1260	0.2100	0.2120

Primer dimensions and tolerances

It's interesting to note that while small pistol and small rifle primers are exactly the same size, the same is not true of large pistol vs large rifle. I have heard of people substituting small pistol and small rifle primers during desperate times, but one should always be careful of pressure increases and the potential for pierced primers if one resorts to such extreme measures. It's always best to use components as they were intended.
Another notable fact is the overlap in tolerances. The largest primer is taller than the shallowest pocket, and the loosest in-spec pocket is the same size as the smallest in-spec primer. It's for these reasons that we sometimes run into so much frustration with certain brands of brass and primers.

 

[billybob44]

Your dimensions don't make sense.
MINIMUM AND MAXIMUM DIMENSIONS OF PRIMER POCKETS
Here is a table of the minimum and maximum primer pocket and primer dimensions. Surprisingly this data isn't too easy to find, so I have done the research for you. Dimensions in inches.

Pocket Type	Depth Min	Depth Max	Diameter Min	Diameter Max
Small Rifle/Pistol	0.1170	0.1230	0.1730	0.1745
Large Rifle	0.1250	0.1320	0.2085	0.2100
Large Pistol	0.1170	0.1230	0.2085	0.2100

Primer pocket dimensions and tolerances

Primer Type	Height Min	Height Max	Diameter Min	Diameter Max
Small Rifle/Pistol	0.1150	0.1260	0.1745	0.1765
Large Rifle	0.1230	0.1360	0.2105	0.2130
Large Pistol	0.1150	0.1260	0.2100	0.2120

Primer dimensions and tolerances

It's interesting to note that while small pistol and small rifle primers are exactly the same size, the same is not true of large pistol vs large rifle. I have heard of people substituting small pistol and small rifle primers during desperate times, but one should always be careful of pressure increases and the potential for pierced primers if one resorts to such extreme measures. It's always best to use components as they were intended.
Another notable fact is the overlap in tolerances. The largest primer is taller than the shallowest pocket, and the loosest in-spec pocket is the same size as the smallest in-spec primer. It's for these reasons that we sometimes run into so much frustration with certain brands of brass and primers.

I agree..I think the OP needs to re-measure, get a new battery for digital calipers, or something..


PS: FWIW: I use this on my Match .223/5.56 cases. This will even out your primer seat..


https://www.midsouthshooterssupply.com/item/0004490379/primer-pocket-uniformer-small

 

[Thegeek]

Correct. .118 and .120

Based on those tables, it looks like I just have a mismatch of tolerances. Both the brass and the primers are both within spec.

Billybob, I'll check out that uniformer.

 

[AmmoManAaron]

I've occasionally run into that with a few cases from mixed range or gun show brass. In those instances I fixed the problem with a dead-length primer pocket reamer (basically a small end-mill). If I got 500 brass like that, I would not be happy. Since the pockets are technically in-spec, I would try a different brand of primer (if you have any on hand) and see if that will solve your problem.

Tolerance stacking is not a fun issue to deal with. You will probably run into it with shellholders too at some point.

 

[Thegeek]

That uniformer is for the case prep station. I looked up on Midway for other options. All the handheld tools had reviews that they weren't good for a large number of cases. But, on this uniformer, the reviews there were several people saying that they added a 3/8" nut and chucked it into a drill. So, that's what I'm going to do. The one thing that bothered me was that it said it would cut to SAMII spec. So is it cutting to minimum or maximum? Also, it didn't indicate if it was adjustable or not. My cases are pretty close to the shallow end. If this cutter only goes to .119, then it'd still not be deep enough.

I'm actually surprised that SAMII specs allow for an unsafe condition. You'd think the minimum depth and maximum primer height would be equal.

 

[Old Syko]

That uniformer is for the case prep station. I looked up on Midway for other options. All the handheld tools had reviews that they weren't good for a large number of cases. But, on this uniformer, the reviews there were several people saying that they added a 3/8" nut and chucked it into a drill. So, that's what I'm going to do. The one thing that bothered me was that it said it would cut to SAMII spec. So is it cutting to minimum or maximum? Also, it didn't indicate if it was adjustable or not. My cases are pretty close to the shallow end. If this cutter only goes to .119, then it'd still not be deep enough.

I'm actually surprised that SAMII specs allow for an unsafe condition. You'd think the minimum depth and maximum primer height would be equal.

No idea what you would do with a 3/8 nut since the stud (which also serves as an adjuster) is 8x32. Cutting depth is fully adjustable on the tool itself which makes any min or max irrelevant.

That said, after loading hundreds of thousands of rounds over the years I have never run into primer pockets so shallow to cause this issue. Must suck to have such luck.

 

[Thegeek]

I think the 3/8 is the wrench size for the nut, not the thread size. Thanks for turning me onto the tool.

 

[NKBJ]

If the primers are sticking up after you firmly seat them, then yeah, possible problem.
That's the acid test and tolerances do not otherwise matter.

If pistol primers are used and slam back against the bolt face because of being so far below the base of the case that they have time to accelerate, then that too can eventually (sometimes) create problems. But I've loaded rifle cartridges with pistol primers and well, never had a problem. Me myself, after almost five decades of reloading, the huge differences between primers makes me just use what works and make work what I have. Some are big, some have hard cups, some thin cups, some have more power though not "magnum", be they labeled pistol or rifle, match, magnum or standard. But then again, I don't magnumize reloads either.

 

[Thegeek]

So, now I'm pissed. The uniformer cuts so slow and trying to hold the brass is a dangerous game. I think the best course of action is to try and see if there's some shorter primers available. I'm using CCI400 now. Anyone want to mic some other brands for me?

 

[AmmoManAaron]

So, now I'm pissed. The uniformer cuts so slow and trying to hold the brass is a dangerous game. I think the best course of action is to try and see if there's some shorter primers available. I'm using CCI400 now. Anyone want to mic some other brands for me?

Not sure how much help this will be since most of my reloading supplies tend to be older stock, but here are some measurements from my relatively newer primers (1990s or newer). I measured four of each at random and will give the minimum and maximum I measured.

Rem 7 1/2 Bench Rest: 0.1165 to 0.1180
CCI 400 "blue box": 0.1185 to 0.1195
Win WSR "white box": 0.1155 to 0.1165
PMC SR "heavy metal free": 0.1165 to 0.1175

Of my samples, the CCI 400 (what you were trying to use) were the tallest and Winchester WSR "white box" were the shortest. Different production lines within a brand and wear on the machinery over the years will cause changes in the dimensions - these are very small numbers we are dealing with and there are no guarantees that what I measured on my primers will hold true with something on the shelf today. Good luck and let us know how things work out for you.

 

[Thegeek]

Thanks for doing that. Looks like I'll be buying some Win WSR primers....