243 Lapua brass

[LWILLIAMS]

I recently loaded up another 200 rounds of 243 lapua brass to fire form out to 6mm CM and while shooting this weekend I noticed quite a few of the rounds would not fire. The primers are sitting down in the cases quite a bit deeper then the ones that will fire. The last lot of brass had no problems but these two boxes are of the same lot. Is there any way that lapua could of reamed out the primer pocket to deep on some and not on others or is it more possible that CCI had some short primers. All primers were set with a RCBS hand priming tool and loaded with 47 grains of H1000 and topped with a 115 dtac. Any thoughts, not I have to pull a shit ton of bullets. FML

 

[John L]

Re: 243 Lapua brass

I am going to guess Chad did your rifle. If your using the 6 Competition Match (not Creedmore) the bullets need to be seated into the lands for the fireform loads. I have found if I use a tiny bit of Imperial sizing wax on the outside of the cases it helps a lot.
I don't use Lapua brass as you will get a donut at the base of the neck. There is a way to cure it but it takes more time than I am willing to put into it. Winchester has worked great so far and I shoot my fireform loads in matches as I have found no difference in accuracy.

 

[Voracious]

Re: 243 Lapua brass

Headspace.

 

[LWILLIAMS]

Re: 243 Lapua brass

Yes Chad did the rifle, and the bullet is in the lands. The last lot of lapua of a different number had no problems. From the case head to the primer, the primer is recessed 0.010 where other primers are flush with the case head. I guess I will pop out the primers and see if it is in the brass. I will measure from the case head to the bottom of the primer pocket of the lot I had no problems with and see if I come up with different numbers.

 

[LWILLIAMS]

Re: 243 Lapua brass

Just measured on the current lot in question and from the case head to the primer the depth varies from .004 to. 010. Maybe bad batch of short primers?

 

[sandwarrior]

Re: 243 Lapua brass

Oooohhh...I thought it was common knowledge to neck up same diameter necks to .257 or 6.5mm (one or two calibers) then neck size them back down.... So that they had a slight interference fit between the .257/6.5mm and you could size them that way.

If not firing then you need to pull them, do that, re-powder them and fireform them that way. That, IMO, is the only way to do it, as taking the chance you are, the way you described it, leaves the whole case a chance to expand in every direction. I've always found (I've done it your way too, and lost

) that necking up for a base size then down to the size you want is the way to go.

And, FWIW, I ruined 100 pieces of Lapua 6mm ppc doing it that way.... They were gimme's, so nothing to cry over...riiiiiighhht

 

[linedrive301ft]

Re: 243 Lapua brass

LWilliams, had similar problem when I was fireforming for my
6CM. I took those loads down and started over. The second time on fireforming they were all GTG.

Since the initial firing I have not had any problems.

Fireforming load was 49g of Retumbo shooting 100g SP

Are you touching the lands with your FF load?

 

[John L]

Re: 243 Lapua brass

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWILLIAMS</div><div class="ubbcode-body">Yes Chad did the rifle, and the bullet is in the lands. The last lot of lapua of a different number had no problems. From the case head to the primer, the primer is recessed 0.010 where other primers are flush with the case head. I guess I will pop out the primers and see if it is in the brass. I will measure from the case head to the bottom of the primer pocket of the lot I had no problems with and see if I come up with different numbers. </div></div>

I figured you knew all of this but I was just covering basics. I have had no problems with Winchester brass. As I said I have not tried Lapua in my gun. Not sure what to tell you, maybe check the firing pin for gunk?

 

[LWILLIAMS]

Re: 243 Lapua brass

I knew about the dreaded dougnut in the neck and just planned on reaming it out. Oh well I guess maybe I will switch to the winchester and put the Lapua up for trade for some 223 or just save it for the next 243. I will also check the firing pin. Time to go through it step by step and eliminate all possibilities till I find my gremlin.

 

[sandwarrior]

Re: 243 Lapua brass

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWILLIAMS</div><div class="ubbcode-body">I knew about the dreaded dougnut in the neck and just planned on reaming it out. Oh well I guess maybe I will switch to the winchester and put the Lapua up for trade for some 223 or just save it for the next 243. I will also check the firing pin. Time to go through it step by step and eliminate all possibilities till I find my gremlin.</div></div>

LWILLIAMS,

All brass is going to have a 'doughnut' if you neck it up. All shoulders are pretty much made heavier than necks are is why. So, when you change shoulder material to neck you have to turn it down. So, don't trade off that Lapua brass. Just work it down right and you'll have it for a long time to come.

 

[John L]

Re: 243 Lapua brass

Sandwarrior,
With this chambering you will not get a donut with the Winchester brass, only the Lapua. The Lapua has a more significant change in the neck/shoulder thicness than Winchester.

 

[sandwarrior]

Re: 243 Lapua brass

Yes, the Lapua has a more significant change than the Winchester, but you will still get a change that you 'should' turn off. Believe me, there is enough there to make it an accuracy issue.