Minimum Case Neck Trim to Thickness

[Dave Brown]

What would be the minimum neck thickness you would want to trim 308 win lapua brass to and is it common to see as much as .0025 variance in the virgin necks out of the box?. I measured 10 cases out of the box after expanding and the low was .014 with the high as much as .016 to .0165.

 

[CatShooter]

What would be the minimum neck thickness you would want to trim 308 win lapua brass to and is it common to see as much as .0025 variance in the virgin necks out of the box?. I measured 10 cases out of the box after expanding and the low was .014 with the high as much as .016 to .0165.

I don't measure necks (or anything else) until the cases have been fired. Too many irregularities when they are fresh out of the box.

 

[LHSmith]

What would be the minimum neck thickness you would want to trim 308 win lapua brass to and is it common to see as much as .0025 variance in the virgin necks out of the box?. I measured 10 cases out of the box after expanding and the low was .014 with the high as much as .016 to .0165.

I don't measure necks (or anything else) until the cases have been fired. Too many irregularities when they are fresh out of the box.

That's odd. I would think to be competitive (as in wanting to win the match) one would want to remedy those irregularities or cull those that can't be corrected especially if one finds new brass often performs the best.

 

[expiper]

Brownie,,,I have used em as thin as .0085 in "B"enchrest cals,,,and if you didnt eject em out on a pad they could/would get dinged up on a regular basis,,,In my senior years I like em turned to .012" or thicker if possible ,,,Roger

 

[CatShooter]

What would be the minimum neck thickness you would want to trim 308 win lapua brass to and is it common to see as much as .0025 variance in the virgin necks out of the box?. I measured 10 cases out of the box after expanding and the low was .014 with the high as much as .016 to .0165.

I don't measure necks (or anything else) until the cases have been fired. Too many irregularities when they are fresh out of the box.

That's odd. I would think to be competitive (as in wanting to win the match) one would want to remedy those irregularities or cull those that can't be corrected especially if one finds new brass often performs the best.

That's odd. I don't recall saying anything about shooting a match with unfired brass. I have not found the performance of new brass to be the best - if it were, we'd all be shooting new cases and selling the fired cases for scrap.

 

[jonbearman]

I think what Roger is saying is you cant shoot a tight neck without turning first.

 

[Joe Salt]

Yes It won't fit.What size neck on the reamer. Maybe its a no turn?

Joe salt

 

[Martin52]

What would be the minimum neck thickness you would want to trim 308 win lapua brass to and is it common to see as much as .0025 variance in the virgin necks out of the box?. I measured 10 cases out of the box after expanding and the low was .014 with the high as much as .016 to .0165.

My last 100 cases (and probably most other purchases) of new Lapua 0.308 brass had a case neck thickness variance of 0. 001, roughly between ~ 0.0145 and 0.0155.

Time, proximity of a match, other demands etc usually dictates whether I turn new brass or turn after the first firing. Unturned new brass I'll generally shoot at the shorter distances first.

My experience with new brass is that I have to it turn down to 0.0140 for consistency in neck thickness.

Martin.

 

[LHSmith]

That's odd. I don't recall saying anything about shooting a match with unfired brass. I have not found the performance of new brass to be the best - if it were, we'd all be shooting new cases and selling the fired cases for scrap.

Ever heard the saying " new brass can cure a lot of ills"?

 

[CatShooter]

That's odd. I don't recall saying anything about shooting a match with unfired brass. I have not found the performance of new brass to be the best - if it were, we'd all be shooting new cases and selling the fired cases for scrap.

Ever heard the saying " new brass can cure a lot of ills"?

That one is not on my list...

 

[Dave Brown]

Brownie,,,I have used em as thin as .0085 in "B"enchrest cals,,,and if you didnt eject em out on a pad they could/would get dinged up on a regular basis,,,In my senior years I like em turned to .012" or thicker if possible ,,,Roger

Thanks, I have a .338 neck and need to turn them to .013

 

[Dave Brown]

Yes It won't fit.What size neck on the reamer. Maybe its a no turn?

Joe salt

.338 neck so I need to turn to .013

 

[Joe Salt]

You will still want .003 clearance. .013 should be Enough! See how the shoot fire forming.

Joe Salt

 

[dcali]

I just did some detailed measurements of a fresh box of Lapua .308 - 50 cases worth. I found that if you turn to just under .014, you turn 100% of every case. Whether or not that will work with your chamber neck is another question. I like to leave at least .003" and preferably about .005".

Interestingly, I found that it's not terribly uncommon to find a couple cases per box where the neck thickness varies by .001" on the same case - a variation of 7% from one side of the neck to the other. I believe that could matter when the case neck opens up to release the bullet. Most cases are much less than 7%, but that one or two per box that are could contribute to those head scratchers that land just off target. Then again, I've never tested this to see if it's actually true.

 

['Freak]

You'll may find this one interesting: http://forum.accurateshooter.com/index.php?topic=3866901.0