I loaded up some rounds I was testing for my Ruger Ranch 300blk rifle. Well I ran out of regular primers and loaded about half of them with benchrest primers (I mis-bought them a while back). Anyways, my gun didnt pop one of these. Shallow divots in the primer and no bang. All the other regular primers fired fine. Are they made harder?

Should I be alarmed...or just get normal primers from now on?

thanks

They are harder/thicker. Might be time to replace the firing pin spring but I'd just get normal primers.

The gun is practically brand new. Less than 50 rounds though it.

How deep did you seat the BR primers in your brass? Flush, below flush, raised primer? If below flush, exactly how deep below flush? And what "regular" primer were you using?

Yes, the BR4 primers have a thicker cup, but they should easily ignite if seated correctly. A "regular" primer to me in a full power supersonic round in the blk out is a magnum primer.

I just push the primer with my press until I get the first feeling of resistance. I didnt know to adjust how deep primers seat. Learn something new every day.

I typically feel one here and there to feel to see if its flush...and most are. I will be more aware of how I am seating.

thanks

normal being cci small rifle primers (not benchrest or not magnum)

That might be your issue. Primers need to be .003" to .008" below flush for optimum seating depth. I try to get my primers about .003-.005" deep, as that is about the sweet spot for primer depth.

If the primer is flush with the case head, the anvil may not flatten out in the primer pocket, and when the firing pin hits it, it has some space where it won't crush against the anvil. When you seat a primer, the anvil (or inside posts) make contact with the bottom of the primer pocket and have a solid base for the firing pin to strike, or crush the primer compound. Also, if there is debris inside the pocket, and you stop seating once you "feel" resistance, the anvil could be off the bottom, and not allow a good firing pin strike. Try seating it deeper, and it should work for you. Measure the depth with the other end of your caliper, and get them to about .003" to .004" deep, and then try them.

I hope this is the issue an its not just a fault with the gun. I dont really want to have to deal with sending it back...their are reports of Ruger just sending a whole new gun. This gun was stacking rounds on top of each other...I like how it shoots.

Check your primer seating depth, and I will bet you will find your answer. When I have had issues with primers not going bang, it's generally the seating depth. If you shoot enough, you will come across a few primers that are defective, but that's rare.

out of curiosity I seated a primer into a cartridge and made sure it was slightly recessed. My calibers wont measure down that way, but I made sure the pocket was very clean and made sure it seated all the way down.

Anyways, the primer fired when I tried. I didnt load a round or powder or anything, just the primer.

I will load a couple more to verify and then consider it solved it they all go bang.

thanks for your help

Awesome!!! Funny, I always enjoyed shooting off just a primer! It makes for a big bang and mini fire ball out the barrel.

I once fired a round in a 7mm STW without powder, and the primer's power pushed the 150 Sierra GK a few inches down the rifling, it was a pita to get the bullet out with a Dewey rod and a hammer. I skipped a case when filling.

Chad, what's the end difference in using a non magnum primer vs a magnum?

I fired off probably 15 more only primed cases and all but 2 popped. Why didn't the 2 pop you think? The ones that go bang have a clear divot where hit but the ones that don't just show a shallow, subtle dent.

Is it very cold when you tried to shoot the gun? It happened to me once during a very cold hunt, the grease / dirt on the firing pin spring was hardened during the cold spell and hampered the spring's 100% function resulting in light primer strikes. You may want to check your firing pin spring also, clean it and reinstall it and see if it helps.

Magnum primer will give you more energy to burn high amounts of propellant, make sure to back off a half grain and work up when using magnum primers. It's hotter than standard primers.

It was today in Texas...so not very cold. I guess I need to break down the bolt...or find out how to.

Is this hard to do?

No its not hard to, googling You Tube shows how to disassemble and clean and reassemble. Maybe check the firing pin spring to see if its weak. Try to follow Chad's primer advise before you do the bolt disassemble. Hope you find out what the problem is.

What method/tool are you using to seat primers?

I googled and I read that there are some issues with light primer strikes on the Ruger Ranch 300 Blackout, some issues with the bolt. You may want to contact Ruger about this issue.

My guess is like Chad's primer seating depth. Not deep enough and the primer will seat a little deeper in the case but with it moving it will not make contact with the anvil most of the time. Often you can shoot those a second time and they will fire due to the primer having been seated deeper by the firing pin (not the recommended way to seat primers)

The CCI small rifle BR primers use the same cup thickness as the small rifle magnum primers. If you were to change a load from using standard primers to magnum primers reduce the load a little say .3 grains and work back up if needed.

On primer seating depth the primer should be visibly below the surface of the case. When seated correctly you will be able to see that it is deeper and feel it with your fingers. The depth below the case head should be about the width of a human hair or a little more which averages 3 to 5 thousandths.

Open the jaws on your caliper until the square shaft on the other end opposite of the jaws is flush to the end then zero it, seat a primer, then using the caliper set the back of it (not the jaws) flush across the brass and line up the square shaft on top of primer, back off the jaws until it touches the primer and there's your seating depth measurement.

What tool are you using to seat your primers? You have made good progress to getting more primers going off, so you are definitely on the right track. If you are using a hand held primer tool, they often have varying amounts of primer depths. They are a great tool and easy to use, but they lack precise and repeatable primer depth from round to round. I use a press mounted Lee Auto Prime 2 to seat primers. It's the only fast method I have found that allows me to control the exact seating depth of the primer from all the different rounds I load for.

For now, I would measure each primer depth to figure out what your tolerances are. I'm pretty sure it's the seating method and/or primer depth causing the issue. The magnum primers do take a little more effort to go off, but should easily be within normal specs of the rifle to ignite them. If you can dissemble the bolt and clean it out easily, this will help eliminate some variables causing your issues.

I like using small rifle magnum primers for any supersonic, full power load in the 223/300 blk out. Most of the time the powders used are a ball powder, and a magnum primer goes well with a ball powder. Could you use a standard primer, sure. I just like the magnum one's.

Here's a Youtube video I quickly found that shows how to use your caliper to measure primer depth.

https://www.youtube.com/watch?v=aa_hZc4O9nE

A quick google search provided that there is a plethora of this same exact problem on this same exact gun. Most dialing back to a headspace issue im guessing in the chamber. Im sending it to Ruger to make sure.

An over sized chamber can easily lead to this, if that's the issue. Measure your fired cases and compare them to SAAMI drawings. This will tell you if it's a head space issue in your rifle.

Fired casings in this situation would be shorter right? But would the fired case not have stretched a bit? Making this measurement inaccurate.

The fired case will form to your chamber. If there is a head space issue, the case would grow and stretch to the chambers dimensions. You can measure the fired cases and get some readings and compare those readings to SAAMI chamber dimensions. This may tell you if you have a head space issue.

Also, what brass are you running? Did you resize this brass, or is it new? If the brass is under sized, it can lead to the same issue.