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

[Changeling]

Using the "bent paper clip" method one can usually feel the slight indentation circle at the web inside the cartridge where the brass has been stretched/reduced in size. I've done this many times!

Use a small paper clip that is "springy", not a thick one that is stiff, works better. 8)

Also make sure the bent end you probe with is filed/sanded to a sharp point like this
___________)

 

[PALarson]

Several knowlegable fellas have hit on the most likely problem. New brass often has minimum head spacing I suggest as others have that you
measure HS before and after firing. I suspect that there is several thousands difference and that is probably the reason for the flatening of primers. I would
bet with the loads that you are using that if you adjust your dies so that you only bump the shoulder a couple of thousands that your problem is
gone.

 

[minnesotamulisha]

I received the correct headspace comparator in the mail today. After measuring fourteen pieces of fired brass, the average is 37.68mm.

Looking at a dimensional drawing of the 6.5x47 that I found on accurateshooter.com, I am .68mm over the SAAMI spec which is 37.4 +0/-.2mm.

I am using mm because the drawing is in mm and there will be nothing lost in the conversion.

Can I bump the shoulder using a FL die to bring a case to 37.3mm and use it as a go gauge, and use a piece of masking tape as a no go gauge?

 

[stansrifles]

My suggestion to you is get a set of headspace gauges an set headspace properly an don't look back throw other cases away before you end up with crap in your face I don't care what everybody else tells you I do this crap for a living an what I am reading stinks.
Stan

 

[Drop Port]

You need to stop worrying about factory measurements and concentrate on your chamber. Get your gauges and check head space on fired brass (shoulder) against your factory sized brass to see what is going on Period.
You can't full length size without knowing if you are bumping the shoulder even further than it should be, get gauges.

Don't worry about a thing until you know these measurements, until then it is speculation, gauges don't lie.

 

[minnesotamulisha]

I used the .375 comparator to measure the virgin brass last night. I don't have the info with me, but I want to say the new brass was measuring 37.13mm. I will double check when I get home tonight. I'm still waiting on the guy with the head space gauges to get in touch with me.

Thanks again for the help. It is very much appreciated on my end.

 

[Mega]

I am using the Hornady Headspace Gauge with 0.375" Insert on Mitutoya Calipres and measure an Unfired Lapua 6.5x47 Case at 1.4590" (37.06mm) a number of fired cases from three different rifles / chambers measure 1.4590" (37.13mm) which is a case length growth of just 0.003". All chambers are custom from three different gunsmiths / reamers and all are different neck diameters but a fired case measures the same, fired about 6 times. I have several hundred new cases, all the same batch.

If you are getting 0.020" case growth then I'd say that is a big problem and your Headspace needs fixing before going forward with your tests.

Some people like setting up headspace so bolt closure has a slight resistance (crush fit) but I'd advise against that. Bolt should close without resistance of any kind, firing pin removed. I don't like the idea of stressing my locking lugs and I still grease the lugs before firing every detail, 7 rounds on average. After several hundred rounds the lugs show no sign of wear. All these rifles are very accurate, less than 0.2 MOA and one is closer to 0.1 MOA, as long as I do my part which is easier said than done shooting up to 600 yards roughly. Close range accuracy is a little different when one has to contend with conditions and it all falls apart due to operator error / lack of experience.

Don't fire any more until the headspace is fixed then fire one new case and check all dimensions, case diameters should be checked with an accurate quality Micrometer not Calipres. I use a Mitutoyu (resolution 0.00005").

 

[minnesotamulisha]

I've measured a dozen or so new cases and I am getting 37.23mm for an average length.

 

[Mega]

There is no guarantee that the Gauge Inserts are the same so I would not compare my figure for an unfired case, go by your own measurements but the vital point is the difference between fired and unfired which should only be a few thou.

Edit... I also use a Hornady modified Anvil Base so I am measuring from the whole case head not a part of it by just using the calipres blade.

 

[minnesotamulisha]

Thanks Mega. I may have to look into the anvil base, but for now, my Mitutoyo is working so I'll leave it alone.

When I measure the once fired case, do I then compare that against a new case? I am thinking I should measure these parts of the case:

1. Headspace
2. Body dia. near the shoulder
3. Body dia. near the case head
4. Neck dia.

Is there more?

What is acceptable growth of the case? Would it be only a few thou for each measurement?

Thanks,

Adam

 

[nosualc]

MM,

You can measure things every which way, but you're dealing with an unknown in the headspace of this rifle. In this case, evidence points to the headspace being too long.

If this were me, I'd get a real headspace GO gauge, and set the headspace myself. It's a Savage with a barrel nut, right?... easy peasy. Borrow a gauge or pay the $30. This is the only way you'll KNOW that it's correct.

Then I'd throw away any brass I had shot with it previously. Taunting a case head separation to save a few bucks is foolish, IMO. The stuff is expensive, so I'd cry a little about it first.

Then I'd start with a 2-3 pieces of virgin brass. Measure datum to base before and after firing. Note that virgin brass is always a little shorter than min spec. The measurement will grow after 1 firing, but it had better be far less then .020".

Now I'd have 2-3 pieces of once fired brass and headspace I can have confidence in. I would then proceed to use those 2-3 pieces to properly set my FL die (this is a process in and of itself).

-nosualc

 

[Hoier]

When I first started with the '47 I started out piercing primers on mild loads so I measured a few and they were growing .013". I had some cheap Amaxes someone gave so I jammed them pretty hard and finished fireforming the rest of my brass. Just like fireforming a Dasher. Now life is great.

 

[minnesotamulisha]

I finally received the go gauge. I measured the go gauge using the Hornady 375 Headspace Comparator, and measured 37.28mm.

When setting headspace, I DID remove the ejector and extractor as to not give any false readings.

After setting the headspace, I added .004" shim to the go gauge and my bolt would not close.

I have 5 pieces of factory Lapua Ammo and taken the measurement to the datum and have written it in Sharpie on each of the 5 pieces.

I will be headed out to the range this morning and I will be bringing all my measuring tools and recording the changes on all the rounds fired.

I will post up results later.

Thanks everyone for the help.

 

[Drop Port]

Do yourself a favor, I just noticed that you started with full length sizing new brass. How did you size it without gauges? You could have created your problem by excessive sizing / bumping of the shoulder.

If you have a piece of new unmolested brass from this lot, compare it to a piece you previously sized but did not fire and see if your die setting created more headspace.

 

[minnesotamulisha]

I just got back from the range. My 5 pieces of brass measures the following:

37.23mm
37.25mm
37.25mm
37.26mm
37.29mm

After firing these rounds, here's what I measured:

37.31mm
37.28mm
37.30mm
37.31mm
37.30mm

I then measured the other 33 rounds that I fired.
The measurements were all between 37.29 and 37.32mm with 27 of those measuring 37.30-37.31mm.

I believe I have the issue solved. None of these rounds had even close to the flat primers I was experiencing earlier.

Thanks to everyone for all the help!

On a another note, I fired a three round group out to 515 yards. I put all three shots in less than 2.25"!

Now to get started on load development and mimic the Lapua factory rounds!

 

[AckleymanII]

Full length sizing new brass, there is a screw up. You probably pushed the shoulder back too far if you have 0.020 growth.

Old freak is dead nuts right on.

I would throw all that brass in the trash, start at the start and don't full length size new brass, neck size only.

Keeping that old brass around may just confuse the heck out of you on what you are doing....keep things simple.

We all have to learn the hard way! Enjoy the ride!

 

[fourpower]

forget the varget and go to h-4350. I load all the berger weights in my 6.5 and use 40grs for all of them. put them at .005 off with .001 neck tension zero headspace. 130s average 2985fps=140s 2835fps. I now only shoot 140 hybreds same load but it shoots lights out. bugholes @ 100yds 4out of 5 shots hit on 18in plate @ 1400yds if not to much wind! laupa brass is just great. I have yet to lose a piece of brass and if I told you how many reloads I have on my brass you would call me on it! all I do is anneal every time after first 5 reloads and check necks and turn them so they are all the same. have not had to trim them yet. laupa brass rock on!!

 

[delivery_boy]

is it possible the use or magnum primers is causing a pressure spike above what is usual with Varget?

I know a couple of guys running over 38gr of Varget (AR2208 here in Oz) with out pressure issues

Delivery_boy