Dumb new Lapua brass question

[DIANEB]

Should I size and trim new Lapua brass?
The brass seems a little hard to size...

Thanks in advance ??

[603 Country]

Depends on who you ask. I always trim the Lapua brass, but usually don’t do a full resize. The main reason I trim the brass is that I use an RCBS Trimpro with the 3 way trimmer and get the case mouth like I prefer.

[DIANEB]

Depends on who you ask. I always trim the Lapua brass, but usually don’t do a full resize. The main reason I trim the brass is that I use an RCBS Trimpro with the 3 way trimmer and get the case mouth like I prefer.

Thank you...

[37L1]

I mandrel the neck and chamfer. No trim or full length size.

[Pwrbomb1970]

No resizing of new brass. It’s already at the smallest size it will ever be. Sizing it is just working the brass more than you need to. I always look at my brass and measure length to ensure concentric length. I may trim to get that but it’s not always necessary as once again you are trimming away brass from your new case thus less times you are gonna get to fire it. Make sure your case mouth is round. Run it through a mandrel of appropriate size if it isn’t. I have never had to do that with Lapua. Chamfer inside and outside to remove burrs.

[DIANEB]

I mandrel the neck and chamfer. No trim or full length size.

Thanks...

[Klem]

I size for consistent neck tension and chamfer inside necks

[603 Country]

What klem said reminds me of my last batch of loading. It was for 223 and not for the Grendel, but it was all brand new never fired Lapua brass. The bullet seating effort was not consistently the same from case to case. It had all been trimmed and chamfered. After firing those cases and resizing and retrimming, seating effort seemed to be very consistent. Maybe I’ll run the next new batch through the sizing die or at least the Lee collet die before priming and loading.

[Dt219]

What Klem said. I run them through just to even out any necks that’s dented. If dies are setup correctly they probably wont touch the shoulder or body

[DIANEB]

You guys are all great help...
Thank you all...

[Zeneffect]

Yep, just straighten out the necks. Lapua brass should already be trimmed and chamfered new but will get neck dents from shipping..

[Old Bob]

I'll chime in for the neck straightening chore for new brass. I've never had a bunch of new brass that didn't have some pieces with dented or oval shaped case mouths. Used to do a full case sizing, trim & chamfer of the whole lot but found just running all the cases over a mandrel would clean up any bad case necks. What I do then is measure the case lengths to see if any need trimming. Will still chamfer all cases. If any shooter wants good, accurate ammo, you gotta do this.

[DIANEB]

I'll chime in for the neck straightening chore for new brass. I've never had a bunch of new brass that didn't have some pieces with dented or oval shaped case mouths. Used to do a full case sizing, trim & chamfer of the whole lot but found just running all the cases over a mandrel would clean up any bad case necks. What I do then is measure the case lengths to see if any need trimming. Will still chamfer all cases. If any shooter wants good, accurate ammo, you gotta do this.

Ok I did everything you posted and they all are looking great...
One more question, the flash holes are kinda small should I do anything to them?
Thanks again
.

[Klem]

Ok I did everything you posted and they all are looking great...
One more question, the flash holes are kinda small should I do anything to them?
Thanks again
.

No need, Lapua finish of their flash holes is as good as any.

There is an online debate by the long range/bench-rester shooters as to whether Lapua drills or punches their flash holes, and whether that is even an issue. Bryan Litz in his Modern Advancement Volume II reportedly claims they are drilled (I have never read this book). My thoughts are it does not matter as we only worry about whether there is any need for internal chamfering. I have never seen the need to do this with Lapua; their quality control and finish is excellent and no doubt why they are the preferred brand for high-end competition.

If you are concerned about their 1.5mm (0.059") holes being small then it's perfectly fine for primer spit. The only time primer holes are an issue for me is if you tumble in walnut media after removing the primer. if your media is small enough there will be pieces clogging the occasional hole. You can easily check by holding cases up to the light.

European small primer holes 0.059" are a bit narrower than the US 0.062" but Grendel die manufacturers have deprime stems that cope with this without sticking.

No need to drill wider and in fact this may be dangerous. No need to chamfer. I read online that Jack Nary did a test of 6BR flash holes seeing if chamfering or drilling made any difference to results on target. With Bench Rest guns you can see if these minimalist efforts make a difference. Apparently, they did not. So, if Bench Resters can't see a difference then we won't either.

[DIANEB]

No need, Lapua finish of their flash holes is as good as any.

There is an online debate by the long range/bench-rester shooters as to whether Lapua drills or punches their flash holes, and whether that is even an issue. Bryan Litz in his Modern Advancement Volume II reportedly claims they are drilled (I have never read this book). My thoughts are it does not matter as we only worry about whether there is any need for internal chamfering. I have never seen the need to do this with Lapua; their quality control and finish is excellent and no doubt why they are the preferred brand for high-end competition.

If you are concerned about their 1.5mm (0.059") holes being small then it's perfectly fine for primer spit. The only time primer holes are an issue for me is if you tumble in walnut media after removing the primer. if your media is small enough there will be pieces clogging the occasional hole. You can easily check by holding cases up to the light.

European small primer holes 0.059" are a bit narrower than the US 0.062" but Grendel die manufacturers have deprime stems that cope with this without sticking.

No need to drill wider and in fact this may be dangerous. No need to chamfer. I read online that Jack Nary did a test of 6BR flash holes seeing if chamfering or drilling made any difference to results on target. With Bench Rest guns you can see if these minimalist efforts make a difference. Apparently, they did not. So, if Bench Resters can't see a difference then we won't either.

Ok thanks, I was just curious after reading all the pros and cons on the flash holes...

[StoneHendge]

One thing to keep in mind is that you will need to tweak your load by a few tenths once the brass has been fired. Unless you are small base sizing, your fired brass will have slightly larger volume after your first sizing.

[Mesa1978]

I size for consistent neck tension and chamfer inside necks

This. A box of Lapua comes from multiple machines and varies in neck tension, however slight.

[Zeneffect]

Iduno, for 1st firing I care a lot less as i was not in control of the sizing process. Sd and es are basically never as good as after firing and resizing. Once fired from the intended chamber, then the attention to detail becomes hypercritical. I would rather have my case capacity established for my chamber than by factory dies and work from there. new brass I always just use as plinkers or sighters. Anything I care to establish reference groups, or compete with will be fired brass from that gun.

[DIANEB]

Thanks all...
The Lapua brass will only be used in my bolt action rifle...

[StoneHendge]

Iduno, for 1st firing I care a lot less as i was not in control of the sizing process. Sd and es are basically never as good as after firing and resizing. Once fired from the intended chamber, then the attention to detail becomes hypercritical. I would rather have my case capacity established for my chamber than by factory dies and work from there. new brass I always just use as plinkers or sighters. Anything I care to establish reference groups, or compete with will be fired brass from that gun.

I've shot PRS matches with virgin Alpha brass and had no difference in velocity variation between the virgin and subsequent loads after tweaking. Lapua or Peterson will be next because I don't think the Alpha primer pockets will last as long as advertised, and I won't hesitate to do it again with either one of those.