6.5x47 Flattened Primers.....Is this common?

[dkhunt14]

You can use a rifle case and a caliper. Find something that goes over the case mouth and fits about halfway on the shoulder. Measure a fired case with this and caliper and measure again after sizing. It will show you what you bumped the shoulder. You can drill a hole in a piece of round aluminum about an inch long. The hole should be big enough to let it go in the middle of the shoulder. Matt

 

[minnesotamulisha]

Thanks dkhunt. I will give that a try.

 

[SG4247]

Here is an example of where my firing pin to bore clearance did not agree with the pressure created by the load combination in 6.5x47.

I believe this is a CCI #41 primer, 38.5 grains of Varget and the 123 Scenar.

Speed was right at 2900 with a 22" Krieger.

 

[minnesotamulisha]

Ok. I sent my 308 headspace measuring tool which is .400" ID. New brass is measuring 1.4435-1.4445 inches, and once fired brass is measuring 1.4625-1.4640.

Is this a head space issue? Do I need to be concerned?

 

[JohnKielly]

If as I first postulated, your cases are somewhat underlength for the chamber, you might try shooting the same loads in once fired cases that are sized on the neck only, or if you use a FLS die, partially sized so the body is not changed.

No signs of primer flattening in that case would confirm my thoughts.

 

[nosualc]

MM,

I think primer reading is a pretty poor way to judge anything.

As long as you're not piercing primers, I don't see that you have a problem, at all.

-nosualc

 

[Drop Port]

MM,

I think primer reading is a pretty poor way to judge anything.

As long as you're not piercing primers, I don't see that you have a problem, at all.

-nosual

+1 that load would be anemic in my rifle. With properly head spaced brass I don't see any primer sign at all with loads that are guaranteed to blank a primer in a fat pin Rem.

What action are you shooting, my advice for what it's worth would be based on what FB you are running and weather or not you have a .062" pin.

 

[minnesotamulisha]

I guess I'm taken back by the fact the brass grown .020" during firing. I never would have thought it would be that much. Because the Virgin brass grows so much, is it best to fire form the brass to my chamber before I begin load development?


I am running a Savage action. The barrel is a Shilen pre fit, and it is a no turn neck. At least that's what the seller told me and I have zero reason to believe otherwise. I am unaware what the diameter of the firing pin is. Hoping to hit the range this weekend and won't have time to take it apart before then.

I worked up another batch of loads , starting at 36 and working up to 37.5 grains. I will crony these ones and see what happens.

Thanks to everyone for all the input.

 

[Flouncer]

Minnesote, I do not have the experience or expertise as others here . . .. but . . .. from pic shown above, I don't see flattened primers. I see a nice rounded edge.

 

['Freak]

I guess I'm taken back by the fact the brass grown .020" during firing. I never would have thought it would be that much. Because the Virgin brass grows so much, is it best to fire form the brass to my chamber before I begin load development?


I am running a Savage action. The barrel is a Shilen pre fit, and it is a no turn neck. At least that's what the seller told me and I have zero reason to believe otherwise. I am unaware what the diameter of the firing pin is. Hoping to hit the range this weekend and won't have time to take it apart before then.

I worked up another batch of loads , starting at 36 and working up to 37.5 grains. I will crony these ones and see what happens.

Thanks to everyone for all the input.

Push a spent primer part way or completely out then only partially re-seat same, leaving it standing proud of the surrounding case head and standing higher than that ~ .020” you got when measuring using the .400” ID insert.

Manually chamber the case (in clean chamber) and gently close the bolt on it, allowing the bolt face pushing on it to seat the spent primer a tad deeper though leaving it still proud.

Extract the case and using the depth measuring thingy on the end of your caliper, measure how high the spent primer was left standing above the case head, which is same as the amount of clearance left between the bolt face and case head of a fully chambered fired case, its ‘head space’.

If the brass actually is growing ~ .020” from case head to shoulder datum and you're getting same via both measurement methods, then that’s 2x way the heck beyond too much and it needs fixin'.

 

[Flouncer]

I had to read that 2x to understand it. My bad, but that makes sense.

 

[scott_at_vortex]

Ok. I sent my 308 headspace measuring tool which is .400" ID. New brass is measuring 1.4435-1.4445 inches, and once fired brass is measuring 1.4625-1.4640.

Is this a head space issue? Do I need to be concerned?

Sounds like the headspace in your rifle is a bit long. I just measured a new piece of brass out of the box and it measures 1.435 with .400 headspace measuring tool and all my fired brass measured 1.438.

Since that is a prefit Savage barrel I would look into checking and reseting headspace since it is pretty simple to do.

 

[Jose_Luis_G]

I started load development on Friday. I started with Varget at 34 grains and went up to 36.1 in .3 grain increments. I used virgin Lapua Brass which was full length sized with a Redding Benchrest FL die. Using CCI 450 Magnum Small Rifle primers. They were topped with Berger 130 Hybrids, all loaded .020" off the lands.

Berger said to use the same info as the 130 VLD. They provided load data for this bullet and the starting charge was 32 and max was listed at 35.8. Being I am shooting these out of a 22" barrel, I opted to start at 34 instead of 32. Also, I bought this barreled action used and the previous owner was shooting 140 Hunting VLDs over 35 grains of Varget.

I had sporadic primer flattening all the way up to 36.1. I loaded five rounds at each charge, and I would get 2-3 flattened primers with each load. There was no ejector marks or stiff bolt lift and no other signs that would leave me to believe that I was too hot.

I was having chrony issues and only recorded one shot, which was at 36.1 grains, and the speed was 2692 fps.

For you 6.5x47 guys, are you seeing flattened primers? How concerned should I be?

I think that your chamber is a bit tight. It is not important if you take just one caution before reloading.
You should turn the case neck.
I may happen that you chamber does not allow the case neck to expand as much as it needs, and thus, acting as if the cartridge were heavily crimped.
You may know that crimping, apart from other effects, raises the pressure, as it retains the buller for a longer time until it starts moving.
If you turn the case neck, you will find two mayor advantages:
One is to ensure the concentricity of the neck and the bullet.
As the neck thickness is decreased, the retention is lower and the pressure remains in a reasonable level.

Just my two cents.

 

['Freak]

On ignition, the primer is being backed out the pocket ~ .020” to ever reach the bolt face, and soon after the case body forward of the web has to stretch that same ~ .020” as the case head is backed against the bolt face, reseating the primer, and giving the primer its flattened appearance in doing so. That’s ~ .020” clearance between the bolt face and the case head, aka headspace, and twice the .010” absolute maximum headspace I’m seeing on SAAMI drawings.

 

[minnesotamulisha]

I found a local guy who has a set of head space gauges. I will check it when I get them and post up some results.

 

[gotcha]

On ignition, the primer is being backed out the pocket ~ .020” to ever reach the bolt face, and soon after the case body forward of the web has to stretch that same ~ .020” as the case head is backed against the bolt face, reseating the primer, and giving the primer its flattened appearance in doing so. That’s ~ .020” clearance between the bolt face and the case head, aka headspace, and twice the .010” absolute maximum headspace I’m seeing on SAAMI drawings.

+1 for Olefreaks analysis. It appears you have a H/S issue. I also have a Savage 6.5X47L. Will be glad to send you my H/S gauge for you to check/ re-adjust. .............. .020" growth in H/S is waaaaaay out of line. My blue box brass grew in H/S by about .0035" on average.

 

[minnesotamulisha]

Thanks gotcha. If i need them, i will let you know. I also ordered a set of Hornady head space comparators as I am using the 400 and should be using the 375.

 

[gotcha]

Thanks gotcha. If i need them, i will let you know. I also ordered a set of Hornady head space comparators as I am using the 400 and should be using the 375.

You are welcome Minnesota. If you are looking for a COMPARATIVE measurement rather than a precise measurement the .400 comparator body will do just fine for trouble shooting & comparing measurements. PS, I just checked my "stash" and have both the H/S gauge & the .375" comparator body if you need them.

 

[minnesotamulisha]

I got the head space gauges on the way. If I do have too much head space, is it possible to bump my shoulders the .020" that they grew or is this brass scrap now?

Thanks again.

 

[gotcha]

Well, I'm a bit reluctant to say scrap them. On the other hand too much stretch at the web poses a potential safety issue. In my experience (some what limited) The 6.5X47L brass is pretty darned tuff. I'd probably cut a couple cases in half length-wise and see if the thickness at the web has been effected drastically. You could post a pic and ask for opinions.