Reloading 6.5 Creedmoor

[Ernest T]

Here is a visual example of what I'm talking about when I say I'm getting inconsistent tension. I can feel that some bullets take noticeably more pressure to seat than others. The brass in the video has been annealed, lubed, full length sized and then tumbled. The videos were taken as I am trimming the brass to length using a Lee Case Conditioning tool for 6.5 CM, which gives me consistent 1.912" case length. The mandrel, which sets the trim length, measures .259" in diameter. It slides into 80% of the cases like there is no friction between the mandrel and the case. Most of the rest slide in fairly easily, but you can tell they are a tighter fit, and there will be one or two percent of the cases that take some force to insert the mandrel. The expander ball on my Lee Full Length Sizing Die is .262. I don't have a micrometer capable of measuring the inside diameter of the brass, that may be my next tool purchase.

The question is how do I fix it?


http://www.youtube.com/watch?v=aPJFxo1XW5M


http://www.youtube.com/watch?v=wQlZ5WS8TFc

[GrenGuy]

What You are seeing is different neck wall thickness, and perhaps inconsistent spring back, on no turn necks. The solution to what You want at this point in Your shooting experience is the LEE Collet die. Fire Your cases, full length size them just enough to easily fit in Your chamber, without the expander mandrel installed in the Die. Neck size with the collet die. This will align the center of the neck with the center of the case, and size the inside of the neck with about .003” neck tension. Since You have a no turn stock chamber, who cares what the outside of the neck is. After that, if You want less neck tension, then go to the mandrels mentioned previously.

Do this, and it will solve what worries You so at this point in time. But, then there will be the next thing.

The only way I would use a Bushing Die, is if I were turning necks, making the neck wall thickness consistent, and concentric. I don’t want to push the inconsistencies to the inside, causing bullet run out. And, before I turn necks on My 6mmBRA, I run them through the LEE Collet die to center up the necks and push the bad stuff to the outside, where it is turned off.

[Dave Hoback]

Since I had a few cratered primers, I sent the bolt to Desh to work on the firing pin and install the bolt lift modification. This is what the bolt, firing pin and primers look like after the bolt work. I don't see a lot of difference, but the primers aren't cratered at the max load like they were before. I still have not achieved the accuracy or consistency with StaBall 6.5 that I did with the RL-16. Groups are + or - one inch and I don't have any 1/2 inch or smaller groups. I'm thinking I need to start adjusting the CBTO to see if that will tighten up the groups.


https://photos.smugmug.com/Firearms/i-KBGptdJ/0/4baa6bb3/L/IMG_0473-L.jpg

https://photos.smugmug.com/Firearms/i-N4ncpFZ/0/1f263889/L/IMG_0472-L.jpg

Doesn’t look like it was made any shorter. You have just way, WAY too much protrusion. Bring it down to .035” or so & your primers will look beautiful. (Didn’t we go over this? LOL!) Your pin protrusion looks to be like .070”++..

[Ernest T]

What You are seeing is different neck wall thickness, and perhaps inconsistent spring back, on no turn necks. The solution to what You want at this point in Your shooting experience is the LEE Collet die. Fire Your cases, full length size them just enough to easily fit in Your chamber, without the expander mandrel installed in the Die. Neck size with the collet die. This will align the center of the neck with the center of the case, and size the inside of the neck with about .003” neck tension. Since You have a no turn stock chamber, who cares what the outside of the neck is. After that, if You want less neck tension, then go to the mandrels mentioned previously.

Do this, and it will solve what worries You so at this point in time. But, then there will be the next thing.

The only way I would use a Bushing Die, is if I were turning necks, making the neck wall thickness consistent, and concentric. I don’t want to push the inconsistencies to the inside, causing bullet run out. And, before I turn necks on My 6mmBRA, I run them through the LEE Collet die to center up the necks and push the bad stuff to the outside, where it is turned off.

Thanks! I have a Lee Collet die and will give that a try.

[Ernest T]

Doesn’t look like it was made any shorter. You have just way, WAY too much protrusion. Bring it down to .035” or so & your primers will look beautiful. (Didn’t we go over this? LOL!) Your pin protrusion looks to be like .070”++..

We did and I sent it to Desh and this is what it looks like after he sent it back.

[GrenGuy]

Dave is right. Desh shortened the bolt face, as part of the process, but didn’t set the pin pertrusion to .035”. That’s Your job. Put a fired case in Your chamber and pull the trigger. Send us a picture of the primer without the blowback.

[charlie b]

Not using the expanding mandrel in the FL size die creates a small issue when using the Lee collet die. The FL die makes the case neck smaller than the mandrel in the collet die so it takes a bit of force to push the case up into the die. Not a huge deal, but, it makes it feel different.

FWIW, many of the precision shooters consider a .002" neck 'tension' to be the std. Yes, you can use more or less if you want. The point is to make it consistent.

As a reference case, I use an off the shelf Forster FL size die for my 6BR. Seat with a Redding competition die. No other case prep. It shoots consistent 1/2MOA groups (with the proper bullets and load). It will go well over 1MOA with a bad load. I don't anneal the cases, rarely even clean them and I don't clean the primer pockets. I do wipe the carbon off the outside of the case neck, after sizing.

You should be able to get decent groups without tweaking the neck tension. Once you get down to the 1/2MOA range then consider tweaking the 'fine points'.

[Ernest T]

Dave is right. Desh shortened the bolt face, as part of the process, but didn’t set the pin pertrusion to .035”. That’s Your job. Put a fired case in Your chamber and pull the trigger. Send us a picture of the primer without the blowback.

This might be a stupid question, but with a new primer right?

[Ernest T]

Not using the expanding mandrel in the FL size die creates a small issue when using the Lee collet die. The FL die makes the case neck smaller than the mandrel in the collet die so it takes a bit of force to push the case up into the die. Not a huge deal, but, it makes it feel different.

FWIW, many of the precision shooters consider a .002" neck 'tension' to be the std. Yes, you can use more or less if you want. The point is to make it consistent.

As a reference case, I use an off the shelf Forster FL size die for my 6BR. Seat with a Redding competition die. No other case prep. It shoots consistent 1/2MOA groups (with the proper bullets and load). It will go well over 1MOA with a bad load. I don't anneal the cases, rarely even clean them and I don't clean the primer pockets. I do wipe the carbon off the outside of the case neck, after sizing.

You should be able to get decent groups without tweaking the neck tension. Once you get down to the 1/2MOA range then consider tweaking the 'fine points'.

I have shot sub MOA groups, even sub 1/2" groups with my hand loads. When that happens, the SD and ES are usually quite low for the group and when I shoot over 1" groups the SD and ES tends to be much larger. I'm looking for more consistency in my loads and by default, my process. I figure if I can tell a bullet is much easier, or harder, to seat, then I have a situation that probably leads to higher SD and/or ES.

On Edit: Is it normally easier to lever the case into the Lee Collet die than the Full Length Sizing die?

[GrenGuy]

No. Not a new primer. When a round is fired, the explosion inside the case pushes everything back against the bolt face, flattening out the primer. The only way to get a true picture of Your firing pin strike is to put that fired case, with the expended primer, back in the chamber, pull the trigger, and see what it looks like without the blowback. With the firing pin protrusion set at .035”, the pin will bottom out on the fired primer at about .025”. As Dave said, Your pin appears to protrude about .070”, about .035” too much. Not unusual when a bolt head comes back from being bushed.

Yes, a full length die with the expander removed will size the neck. As I said in post 155, I size the the case and bump the shoulder with a Redding Body Die, which does not size the neck. If the sizing expander is left in, it expands the neck on the way out, so IMO, no additional brass working occurs.

[Dave Hoback]

If you say so… :confused: I’m comparing the pictures you posted of your bolt before & after, and the FP doesn’t look any shorter to me.

Before:
https://i.ibb.co/TtbZFNc/A1188-AD3-C698-460-F-86-FC-2-ABBB621-ABB3.jpg (https://ibb.co/NKmXHGx)

After:
https://i.ibb.co/MVtCvrS/D42-E72-F7-F1-F8-44-B3-B77-A-4-D77-EE75-FD9-F.jpg (https://ibb.co/zRB4Mpx)

I don’t see a bit of difference in protrusion. I’m not sure why there is still contention. It’s too long..Period! It’s not a debatable point is all. So insisting it was shortened & therefore good, is folly.

[Ernest T]

Since I had a few cratered primers, I sent the bolt to Desh to work on the firing pin and install the bolt lift modification. This is what the bolt, firing pin and primers look like after the bolt work. I don't see a lot of difference, but the primers aren't cratered at the max load like they were before. I still have not achieved the accuracy or consistency with StaBall 6.5 that I did with the RL-16. Groups are + or - one inch and I don't have any 1/2 inch or smaller groups. I'm thinking I need to start adjusting the CBTO to see if that will tighten up the groups.


We did and I sent it to Desh and this is what it looks like after he sent it back.


I don’t see a bit of difference in protrusion. I’m not sure why there is still contention. It’s too long..Period! It’s not a debatable point is all. So insisting it was shortened & therefore good, is folly.

There's no contention Dave. I said in my initial post that I didn't see any difference. And I didn't say it was different in my first reply to you when you pointed out it was still too long, just that that was the way it came back. I thought Desh was going to shorten it and I guess he didn't.

[charlie b]

I have shot sub MOA groups, even sub 1/2" groups with my hand loads. When that happens, the SD and ES are usually quite low for the group and when I shoot over 1" groups the SD and ES tends to be much larger. I'm looking for more consistency in my loads and by default, my process. I figure if I can tell a bullet is much easier, or harder, to seat, then I have a situation that probably leads to higher SD and/or ES.

On Edit: Is it normally easier to lever the case into the Lee Collet die than the Full Length Sizing die?

Yes, the ES of a group is importan, probably the most important. The SD just does not mean much until you have a lot more data points. I have had quite a few 'blown' groups with low SD's.

If you just use the Lee Collet die to neck size it is very easy for the case to enter the die. It does take a bit of force at the end of the stroke to cause the collet to close on the neck.

If you FL size first without the expander button, it takes a bit of force to expand the case neck with the collet die. It is about the same amount of force as my Lee FL size die requires.

[Ernest T]

No. Not a new primer. When a round is fired, the explosion inside the case pushes everything back against the bolt face, flattening out the primer. The only way to get a true picture of Your firing pin strike is to put that fired case, with the expended primer, back in the chamber, pull the trigger, and see what it looks like without the blowback. With the firing pin protrusion set at .035”, the pin will bottom out on the fired primer at about .025”. As Dave said, Your pin appears to protrude about .070”, about .035” too much. Not unusual when a bolt head comes back from being bushed.

Yes, a full length die with the expander removed will size the neck. As I said in post 155, I size the the case and bump the shoulder with a Redding Body Die, which does not size the neck. If the sizing expander is left in, it expands the neck on the way out, so IMO, no additional brass working occurs.

I already deprimed, annealed, sized and trimmed that brass. I’ll shoot a few rounds and take a pic next week.

[Ernest T]

Another question, how consistent is the length of the brass after it is fired in your gun? This is the brass from the last 60 rounds I shot from my rifle. The rows, from back to front, measured 1.532", 1.533", 1.534", and the single casing in front measured 1.535" CBTO. None of it measured shorter than 1.531". I set the sizing die to bump the shoulder to 1.532" figuring the shorter cases would fit the chamber at that length. People talk like each piece of brass is exactly the same length after its fired, but that's not my case or is the brass falling within .004" essentially the same length?
https://photos.smugmug.com/Firearms/i-LtK8fm9/0/2969ad34/L/IMG_0484-L.jpg

[Whynot]

Personally I would bump the shoulder more-- the most you could be sizing would be .003 and many of them wouldn't be getting any shoulder bump....

As far as the .004 difference- how accurate are you at measuring? If you measure the same piece of brass (without looking at the readout until you are done) 5 or 10 times do you get the exact same reading? I never did with the Hornady comparators....
The .004 difference is not causing bad groups--

[Ernest T]

Personally I would bump the shoulder more-- the most you could be sizing would be .003 and many of them wouldn't be getting any shoulder bump....

As far as the .004 difference- how accurate are you at measuring? If you measure the same piece of brass (without looking at the readout until you are done) 5 or 10 times do you get the exact same reading? I never did with the Hornady comparators....
The .004 difference is not causing bad groups--

Normally, I'd suspect me more than the Hornady Comparator, but I am pretty good with calipers, micrometers etc as I've got quite a bit of experience rebuilding engines.

I just have questions about reloading and what happens to brass when you fire a gun. My Lapua brass measured anywhere from 1.529 to 1.531 when it was new. I swear it measured 1.536 to 1.538 after the first time it was fired. My Lee case trim gauge trims the brass to 1.912 so this brass has been shoulder bumped and trimmed to that length twice now.

On edit: I resized the new brass before I loaded it, but I didn't measure it after sizing so I don't know if it went straight from 1.529 to 1.5737 on firing or if it ended up somewhere in the middle after sizing. I used the standard setup with a FL sizing die which should have sized it to SAAMI specs.

[Ernest T]

It's been a little cool so I haven't been out to the range this week. I decided to see if I could measure the protrusion of the firing pin and this is what I found. From the end of the bolt to the top of the firing pin is .0475". I kept that measurement and zeroed the gauge and measured the distance to the bolt face. That measurement was .059". Then I closed the caliper, zeroed the gauge, and measured the distance from the end of the bolt to the bolt face. That measurement was .1065 which is close enough to confirm my first two measurements were essentially correct. I'm not sure how accurate my caliper is, but its close enough for this exercise. The protrusion is .059". Is that in spec?

Measurement to the top of the firing pin.

https://photos.smugmug.com/Firearms/i-Mr9pWwK/0/be31cd45/L/IMG_0518-L.jpg

https://photos.smugmug.com/Firearms/i-kWK7wbX/0/b9e91f89/L/IMG_0519-L.jpg

Measurement to the bolt face with after zeroing the gauge.

https://photos.smugmug.com/Firearms/i-p4G5xMP/0/9ba6fcf5/L/IMG_0520-L.jpg

https://photos.smugmug.com/Firearms/i-XkFb5fK/0/449eae37/L/IMG_0521-L.jpg

Measurement from the front of the bolt to the bolt face.

https://photos.smugmug.com/Firearms/i-xJPqQT6/0/0c519912/L/IMG_0524-L.jpg

https://photos.smugmug.com/Firearms/i-DKg2jQP/0/0f364b53/L/IMG_0525-L.jpg

[Ernest T]

Dave is right. Desh shortened the bolt face, as part of the process, but didn’t set the pin pertrusion to .035”. That’s Your job. Put a fired case in Your chamber and pull the trigger. Send us a picture of the primer without the blowback.

Here's the picture you asked for.

https://photos.smugmug.com/Firearms/i-gJD6BV7/0/224b1493/L/IMG_0527-L.jpg


What the primer looks like after firing, but before putting the fired case in the chamber and firing it again.

https://photos.smugmug.com/Firearms/i-kdZGbTP/0/d9078f72/L/IMG_0529-L.jpg

Side by side comparison.

https://photos.smugmug.com/Firearms/i-Nvz6F6S/0/a05b9721/L/IMG_0530-L.jpg

[Ernest T]

I think I got all I can get out of the StaBall 6.5 in my rifle. I tried different loads, different CBTO lengths and except for the one below, none of them seemed to work very well, most were wider than 1", some much wider. Shorter lengths did seem to work better than longer.

This is 42.5 gr. of StaBall 6.5 at 2.163" CBTO. I only had 5 rounds of this load and shot the three at the bottom, then adjusted the scope up two clicks and shot the last two. Move those two down 1/2" and its a pretty good group. I'll try some more of this load.

https://photos.smugmug.com/Firearms/i-GZKmpxQ/0/06be7bc3/L/IMG_0533-L.jpg

42.5 grains of StaBall gives me around 2615 FPS average over 20 shots. This group of 8 gave pretty consistent speeds and would be even better without nr. 6. Coincidently, this is pretty close to my best load of RL-16, which performed well. That might be the speed this gun likes.

https://photos.smugmug.com/Firearms/i-DbfBC7x/0/261cdf69/L/IMG_0532-L.png