Rookie Question - Blown Primer

[IndianCent]

I prepared two loads today and had two primer blowouts. I am trying to keep it simple, so please bear with me.

I am using a Zermatt TL3 action with a 26” Shilen ratchet barrel. The barrel has a twist of 1:9.

I am using brand new Starline brass in .223 Rem. with CCI 400 small rifle primers. The bullets are Sierra 69 grain TMK’s (boat tail).

The distance from the head to the ogive is 1.92”, touching the leads.

While my first handload using the 1.92” seating depth was better than the factory ammo, it had a lot of room for improvement.

The Geco factory load measures 1.851” (Ogive to head).

So decided to start there, I loaded the minimum charge of 18.3 grains of IMR 4198 and seated the bullet at 1.857”. The last of the four rounds pushed out the primer (I lost it).

Next, I tried one round of the same load using 18.9 grains of IMR 4198 (that is halfway between minimum and maximum charge. The first round blew out the primer, the shell and primer came out of the action separately.

I know I didn’t over charge as I used either the minimum charge or stayed between the minimum and maximum allowed.

My only explanation would be that the bullet was seated too deep causing too much pressure in the shell before the bullet could exit. Should the bullet ever extend down past the neck of the cartridge?

I only sized the shells full length, no crimp.

I will pull the bullets from the remaining loads until I figure out what I need to do differently. All input is appreciated. Thanks

 

[culater]

I would drop that powder your using and move to a slower powder.

 

[Rob01]

Yup dump that powder and get some VV N135/140 or XBR8208.

 

[ShtrRdy]

The primers are showing signs of high pressure. What are you using for a scale?

 

[spife7980]

That’s a soft primer with too fast of a powder for too heavy of a bullet.

 

[straightshooter1]

I prepared two loads today and had two primer blowouts. I am trying to keep it simple, so please bear with me.

I am using a Zermatt TL3 action with a 26” Shilen ratchet barrel. The barrel has a twist of 1:9.

I am using brand new Starline brass in .223 Rem. with CCI 400 small rifle primers. The bullets are Sierra 69 grain TMK’s (boat tail).

The distance from the head to the ogive is 1.92”, touching the leads.

While my first handload using the 1.92” seating depth was better than the factory ammo, it had a lot of room for improvement.

The Geco factory load measures 1.851” (Ogive to head).

So decided to start there, I loaded the minimum charge of 18.3 grains of IMR 4198 and seated the bullet at 1.857”. The last of the four rounds pushed out the primer (I lost it).

Next, I tried one round of the same load using 18.9 grains of IMR 4198 (that is halfway between minimum and maximum charge. The first round blew out the primer, the shell and primer came out of the action separately.

I know I didn’t over charge as I used either the minimum charge or stayed between the minimum and maximum allowed.

My only explanation would be that the bullet was seated too deep causing too much pressure in the shell before the bullet could exit. Should the bullet ever extend down past the neck of the cartridge?

I only sized the shells full length, no crimp.

I will pull the bullets from the remaining loads until I figure out what I need to do differently. All input is appreciated. Thanks

Rather than change powder. You might first want to try a different primer. CCI-400's have pretty thin cups making them more susceptible to being pierced or blown depending on various conditions. You might want to try something like Remington's 6 1/2's or better yet the 7 1/2's, which have thicker cups.

The base of that case in picture "Primer Out" appears to have pressure sign, where too much pressure can certainly blow out a primer.

 

[IndianCent]

I would drop that powder your using and move to a slower powder.

How can I find out if a powder is suitable for my application? IMR 4198 lists a powder charge for .223 Rem. I thought that meant that the powder is fine to use?

 

[IndianCent]

I would drop that powder your using and move to a slower powder.

How can I find out if a powder is suitable for my application? IMR 4198 lists a powder charge for .223 Rem. I thought that meant that the powder is fine to use?

 

[IndianCent]

That’s a soft primer with too fast of a powder for too heavy of a bullet.

Wow, how can I avoid such a bad combo is the future? What tells me that all these things don't mince well?

 

[IndianCent]

Rather than change powder. You might first want to try a different primer. CCI-400's have pretty thin cups making them more susceptible to being pierced or blown depending on various conditions. You might want to try something like Remington's 6 1/2's or better yet the 7 1/2's, which have thicker cups.

The base of that case in picture "Primer Out" appears to have pressure sign, where too much pressure can certainly blow out a primer.

I have Rem BR 7 1/2 that I can use, but wouldn't that increase the pressure in the case even more?

 

[918v]

That’s a soft primer with too fast of a powder for too heavy of a bullet.

^^^ That

 

[918v]

I have Rem BR 7 1/2 that I can use, but wouldn't that increase the pressure in the case even more?

Yes. That will certainly escalate the retardation.

 

[IndianCent]

The primers are showing signs of high pressure. What are you using for a scale?

I am using the RCBS chargemaster and then I verify the charge with the digital scale from Hornady.

 

[918v]

How can I find out if a powder is suitable for my application? IMR 4198 lists a powder charge for .223 Rem. I thought that meant that the powder is fine to use?

When looking at which powders to use, consider the bullet weight. 223 uses 35-95gr bullets. Choose fast burning powders (4198) for light bullets. Choose slow burning powders for heavy bullets. Choose medium burning powders for medium weight bullets. Don’t choose fast burning powders for heavy bullets.

 

[IndianCent]

When looking at which powders to use, consider the bullet weight. 223 uses 35-95gr bullets. Choose fast burning powders (4198) for light bullets. Choose slow burning powders for heavy bullets. Choose medium burning powders for medium weight bullets. Don’t choose fast burning powders for heavy bullets.

Thank you, I will save that rule from here on.

 

[Emerson0311]

Thank you, I will save that rule from here on.

Often the mid range burn rate powders for a particular load are the simplest to work up. The powders on the fast end of the spectrum for whatever load you are using are the least forgiving I’m my experience. Tolerance stacking of various components, chamber and brass measurements, and your particular reloading routine can leave very little wiggle room between happy and over pressure.

 

[IndianCent]

Often the mid range burn rate powders for a particular load are the simplest to work up. The powders on the fast end of the spectrum for whatever load you are using are the least forgiving I’m my experience. Tolerance stacking of various components, chamber and brass measurements, and your particular reloading routine can leave very little wiggle room between happy and over pressure.

Thanks again, I am copying and pasting this info. I have not seen these guidelines before.

 

[Evintos]

Wow, how can I avoid such a bad combo is the future? What tells me that all these things don't mince well?

Buy and read reloading manuals.

 

[IndianCent]

Is the seating depth of the bullet an issue? The bullet clears the cartridge neck and continues into the body of the cartridge.

 

[Rob01]

Those are two different bullets.

 

[IndianCent]

Those are two different bullets.

They came from the same box of 500 rds from a major distributor.

 

[Rob01]

They came from the same box of 500 rds from a major distributor.

If they did someone screwed up as it looks like a Sierra on top and a Hornady in the case. You can also see the differences in the ogive. Show the box they came in.

 

[IndianCent]

Here are pictures with some more bullets out and the box open and closed.

My question is about the bullet seating depth. The picture shows that the bottom of the bullet extends past the neck and well into the shoulder of the shell. That means that the pressure does not only build up on the base of the bullet but also around the bottom of that bullet inside the shoulder of the shell. Should a bullet ever go below the neck of the cartridge?

I will also measure the exterior dims of the spent shells to see what kind of expansion took place (if any). If the cartridge is still within factory specs, I would think that the primer might be the issue. As Straightshooter1 says above, the CCI 400 primer walls are thin. The brass is brand new, it might take less pressure for these primers to slip out of their pockets. Just a thought.

 

[ma smith]

Use the 7.5 primers and find something powder wise suitable for heavier projos. 69 and 77gr and not standard weight 223, they are considered heavy for caliber.

 

[IndianCent]

Use the 7.5 primers and find something powder wise suitable for heavier projos. 69 and 77gr and not standard weight 223, they are considered heavy for caliber.

I agree, that's going to be my next step. It is very confusing to me that Hogdon will list a range from 18.3 to 19.5 gr for 69 gr bullets, using IMR 4198.

 

[Shifty6BR]

If it were me...I would try a totally different combo...4198 is fast and has a very, very small window between min and max for that bullet weight.

There are more suitable powders.

H4895, N140, Varget ....

 

[Rob01]

Here are pictures with some more bullets out and the box open and closed.

My question is about the bullet seating depth. The picture shows that the bottom of the bullet extends past the neck and well into the shoulder of the shell. That means that the pressure does not only build up on the base of the bullet but also around the bottom of that bullet inside the shoulder of the shell. Should a bullet ever go below the neck of the cartridge?

I will also measure the exterior dims of the spent shells to see what kind of expansion took place (if any). If the cartridge is still within factory specs, I would think that the primer might be the issue. As Straightshooter1 says above, the CCI 400 primer walls are thin. The brass is brand new, it might take less pressure for these primers to slip out of their pockets. Just a thought.

That red tip bullet did not come out of that box. If it did then someone messed with that box and i would talk to wherever you bought it.

Yes the boattail can go below the neck. Will not cause pressure by itself.

 

[Mike Casselton]

Rather than change powder. You might first want to try a different primer. CCI-400's have pretty thin cups making them more susceptible to being pierced or blown depending on various conditions. You might want to try something like Remington's 6 1/2's or better yet the 7 1/2's, which have thicker cups.

The base of that case in picture "Primer Out" appears to have pressure sign, where too much pressure can certainly blow out a primer.

Do not change to a harder primer to mask an overpressure issue.




OP, I know you said this is new brass.
Did you resize it and possibly move the shoulder too far back causing a headspace issue?


Also, reading the rest of the way through this thread it appears you are mixing bullet brands and weight.


Never, ever, do that.

 

[IndianCent]

That red tip bullet did not come out of that box. If it did then someone messed with that box and i would talk to wherever you bought it.

Yes the boattail can go below the neck. Will not cause pressure by itself.

Thank you for your reply on the seating depth, it was a concern I had.
I think I know now where to go from here.

Do not change to a harder primer to mask an overpressure issue.




OP, I know you said this is new brass.
Did you resize it and possibly move the shoulder too far back causing a headspace issue?


Also, reading the rest of the way through this thread it appears you are mixing bullet brands and weight.


Never, ever, do that.

I resized with a Hornady full length die (used it in the past).
The bullets came in a 500 ct box from Hinterland. I did not see the difference in tip color until put the bullets side by side.
Maybe Hinterland repackages bulk lots and that is how this bullet got in there? I would not deliberately mix bullets/lots.

 

[jpjulian]

Wrong powder, wrong primer. Mixed bullets? Seat to 2.260 for mag length or a bit longer if your mag will allow in the bolt gun.

 

[Rob01]

OP here is a pic of my .223 75 ELD-M load with the bullet next to case. As you can see the boattail is in a similar place as your picture although your pic does not show the same bullets. It does not cause pressure. Your powder choice is most likely cause of your issues. I would get a different powder.

 

[IndianCent]

I have CFE223 and BL-(C) 2, I believe these powders should be more suitable for 69 gr bullets?

OP here is a pic of my .223 75 ELD-M load with the bullet next to case. As you can see the boattail is in a similar place as your picture although your pic does not show the same bullets. It does not cause pressure. Your powder choice is most likely cause of your issues. I would get a different powder.

View attachment 8455110

Good comparison, thank you. I just wanted to make sure the that the seating depth was not causing a problem.
I am still trying to find a good way to choose the right powder. I am looking at the Hodgdon on-line manual and I see a burn rate chart that seems to put IMR 4198 right into the middle. What criteria can I use to determine my powder? Hodgdon says I can load 18.3 to 19.5 gr with 4198 but yet my primers blow out at the starting load of 18.3 grain. Varget, XBR8208 and N135/140 was suggested earlier but how do I arrive at those same choices without understanding the criteria?

 

[Rob01]

Look at the burn rate chart and see where 4198 is and then look at the other powders. See how fast 4198 is and why they only recommend 18-19grns. You want powders starting about XBR8208 up to CFE223. That's the burn area that works well with the 69-80grn bullets.

https://bulletin.accurateshooter.com/2022/08/burn-rate-chart-for-reloading-powders-download-here/

 

[IndianCent]

Look at the burn rate chart and see where 4198 is and then look at the other powders. See how fast 4198 is and why they only recommend 18-19grns. You want powders starting about XBR8208 up to CFE223. That's the burn area that works well with the 69-80grn bullets.

https://bulletin.accurateshooter.com/2022/08/burn-rate-chart-for-reloading-powders-download-here/

View attachment 8455125

Awesome, I get it now. I copied loaddata.com as well. I appreciate all the help and will move on from here. Thank You.

 

[DownhillFromHere]

Do not change to a harder primer to mask an overpressure issue.

^^^^ THIS. With a possible exception. Read on for that.

Do primers blow out of factory rounds? If not, there is a huge finger pointed at your reloads - specifically, headspace (shoulder pushed back too far).

Is this primer-popping happening with "used" as well as new Starline brass? I have a large pile of Starline .223 brass and, new, its base-to-shoulder measurement was quite short --> more headspace. You need something like a Whidden case gauge, which makes it very easy to compare base-to-shoulder lengths of fired/unfired/resized brass. If your chamber is cut wrong and an excessive headspace condition exists, the Whidden gauge will reveal it pdq. But if chamber headspace is the issue, I'd expect to see factory ammo showing some sign too.
------
Fwiw, I use CCI 400 primers exclusively for my bolt-action .223. Running Vihtavuori N135 and IMR 8208XBR, I easily get Hornady 75gr ELDMs to 2850 with no pressure signs. I've loaded to higher velocity, but accuracy is marginally better at lower speed, easier on brass and barrel, no concerns about pressure on these 100+ degree days.

I am looking at the Hodgdon on-line manual and I see a burn rate chart that seems to put IMR 4198 right into the middle.

Pistol and shotgun powders burn far faster than rifle powders. They're in burn charts too. (I haven't seen the Hodgdon chart)

Hodgdon says I can load 18.3 to 19.5 gr with 4198 but yet my primers blow out at the starting load of 18.3 grain

Your post said you had primers pop out with CBTO of 1.85 inches. Loading bullets very close to or touching the lands is likely to cause a higher initial pressure spike because the bullet can't get a running start before it hits the lands - but that certainly shouldn't be an issue with rounds loaded to CBTO of 1.85".

I had a similar issue to yours with a Tikka T3X Varmint I had - flattened CCI 400 primers at light charges of appropriate-for-bullet-weight powders. I just lived with it. This is the only time I was comfortable using CCI450 (magnum) primers to mask a pressure sign as the rounds were fine in other rifles. I never had issues with factory ammo. I never had a primer actually blow out of the case or even close to it, though.

Varget, XBR8208 and N135/140 was suggested earlier but how do I arrive at those same choices without understanding the criteria?

You are correct. If the load is shown in the manual and you're starting at the low end of the range, it should be OK.

Keep something in mind, though, as you learn more about reloading: Look at the min/max load range for 4198 - 1.2 grains. Look at 8208XBR - 2.8 grains min to max, over twice as wide. Pressure doesn't rise in a linear fashion with any powder. There will be a load weight at which pressure "hits the wall" and the pressure curve goes dang near vertical. This "wall" occurs more abruptly with faster-for-bullet-weight powders.

-------
*Conclusion: At this point, given what you've said, I suspect something's up with the rifle that's causing early, and potentially bogus, pressure sign - as happened with my Tikka. Blowing out primers is quite a sign, though, so get a case gauge so you can compare your loaded rounds' headspace to SAAMI spec or to a factory round.

Good luck.

 

[Rob01]

The Hornady headspace gauge is what I have used for years to measure shoulder bump.

Hornady Lock-N-Load Headspace Ga 5 Bushing Set Comparator

The Hornady Lock-N-Load Headspace Gauge is a great tool for increasing the accuracy of your loaded ammunition. The Headspace gauge measures from the...

www.midwayusa.com

 

[ma smith]

Keep in mind as you reduce the volume you get more pressure with the same powder charge.

Heres some vids comparing volumes in various brass headstamps.

 

[918v]

I am looking at the Hodgdon on-line manual and I see a burn rate chart that seems to put IMR 4198 right into the middle.

It’s in the middle of all powders, but on the fast side of rifle powders. On the above chart 1-70 are handgun/shotgun powders and everything else is for rifles. 4198 in 223 is like Bullseye in 357 Mag. It’s a fast burning rifle powder.

 

[IndianCent]

^^^^ THIS. With a possible exception. Read on for that.

Do primers blow out of factory rounds? If not, there is a huge finger pointed at your reloads - specifically, headspace (shoulder pushed back too far).

Is this primer-popping happening with "used" as well as new Starline brass? I have a large pile of Starline .223 brass and, new, its base-to-shoulder measurement was quite short --> more headspace. You need something like a Whidden case gauge, which makes it very easy to compare base-to-shoulder lengths of fired/unfired/resized brass. If your chamber is cut wrong and an excessive headspace condition exists, the Whidden gauge will reveal it pdq. But if chamber headspace is the issue, I'd expect to see factory ammo showing some sign too.
------
Fwiw, I use CCI 400 primers exclusively for my bolt-action .223. Running Vihtavuori N135 and IMR 8208XBR, I easily get Hornady 75gr ELDMs to 2850 with no pressure signs. I've loaded to higher velocity, but accuracy is marginally better at lower speed, easier on brass and barrel, no concerns about pressure on these 100+ degree days.


Pistol and shotgun powders burn far faster than rifle powders. They're in burn charts too. (I haven't seen the Hodgdon chart)


Your post said you had primers pop out with CBTO of 1.85 inches. Loading bullets very close to or touching the lands is likely to cause a higher initial pressure spike because the bullet can't get a running start before it hits the lands - but that certainly shouldn't be an issue with rounds loaded to CBTO of 1.85".

I had a similar issue to yours with a Tikka T3X Varmint I had - flattened CCI 400 primers at light charges of appropriate-for-bullet-weight powders. I just lived with it. This is the only time I was comfortable using CCI450 (magnum) primers to mask a pressure sign as the rounds were fine in other rifles. I never had issues with factory ammo. I never had a primer actually blow out of the case or even close to it, though.


You are correct. If the load is shown in the manual and you're starting at the low end of the range, it should be OK.

Keep something in mind, though, as you learn more about reloading: Look at the min/max load range for 4198 - 1.2 grains. Look at 8208XBR - 2.8 grains min to max, over twice as wide. Pressure doesn't rise in a linear fashion with any powder. There will be a load weight at which pressure "hits the wall" and the pressure curve goes dang near vertical. This "wall" occurs more abruptly with faster-for-bullet-weight powders.

-------
*Conclusion: At this point, given what you've said, I suspect something's up with the rifle that's causing early, and potentially bogus, pressure sign - as happened with my Tikka. Blowing out primers is quite a sign, though, so get a case gauge so you can compare your loaded rounds' headspace to SAAMI spec or to a factory round.

Good luck.

Thank you for the detailed outline, I really appreciate your taking the time.
I am using a Hornady case gauge, it took the new brass perfectly. The head was flush in the recess. That changed of course once I had the primer back out. I also measured the head of the blown primer shell and found that it had expanded beyond the new factory shell width. The neck, center and length was only slightly up from the factory measurements.
For now I plan to continue with the CCI 400 primer and reload using the minimum charge of the other two powders I have, CFE223 and BLC-(2). If the primers continue to show signs of too much pressure or the head is out of spec, I will have to reconsider. We'll seee what happens.

 

[IndianCent]

The Hornady headspace gauge is what I have used for years to measure shoulder bump.

Hornady Lock-N-Load Headspace Ga 5 Bushing Set Comparator

The Hornady Lock-N-Load Headspace Gauge is a great tool for increasing the accuracy of your loaded ammunition. The Headspace gauge measures from the...

www.midwayusa.com

Thanks, I am using that. New brass fits perfectly, the blown primer shell sticks out about 3/8", unlike my used factory loads that fit almost entirely in the gauge (before resizing).

 

[IndianCent]

Keep in mind as you reduce the volume you get more pressure with the same powder charge.

Heres some vids comparing volumes in various brass headstamps.

Thank you, I will check them out.

 

[Rob01]

Thanks, I am using that. New brass fits perfectly, the blown primer shell sticks out about 3/8", unlike my used factory loads that fit almost entirely in the gauge (before resizing).

Yeah I am not sure you are using that tool as nothing "sticks out" or "fits in" when using it. It's not a case gauge but measures the shoulder movement at the datum line of the case. Below is what it looks like in use. It allows you to see ow much the shoulder is moving forward and when setting up your dies for only a .001" shoulder bump so you are not over working your brass.

 

[IndianCent]

Yeah I am not sure you are using that tool as nothing "sticks out" or "fits in" when using it. It's not a case gauge but measures the shoulder movement at the datum line of the case. Below is what it looks like in use. It allows you to see ow much the shoulder is moving forward and when setting up your dies for only a .001" shoulder bump so you are not over working your brass.

View attachment 8455405

I thought you were referring to a case gauge. I do have this headspace bushing set. I have not used it yet as I expected to only need it until after I reload to verify correct shoulder bump.

 

[Baron23]

Yeah I am not sure you are using that tool as nothing "sticks out" or "fits in" when using it. It's not a case gauge but measures the shoulder movement at the datum line of the case. Below is what it looks like in use. It allows you to see ow much the shoulder is moving forward and when setting up your dies for only a .001" shoulder bump so you are not over working your brass.

View attachment 8455405

Thank you....after reading the OP's post on this I was about to go to the bench to see WTF he was talking about or if I had dementia and forgot what that thing does.

I have one but mostly use the Whidden case gauge to measure before/after shoulder bump. I do note that with a tool like the Whidden its important to keep it perfectly (and consistently) vertical when tightening as a bit of an angle changes the measurement some.

Cheers

 

[IndianCent]

Thank you to everyone for your input. I learned a lot. I am loading a slower burning powder and have no longer any pressure issues or blown primers, just have to work on tightening up the groups.