problems with too much neck tension

[HSNARC]

Can having too much neck tension have a poor effect on accuracy?

I have a .288 neck bushing in my Redding s type sizing die and im necking down Win 7-08 into .260 rem. I bought the die/bushing before i had components to make a loaded round to measure.

Now i measure some loaded rounds at around .292 so that means i have around .004 neck tension, is that way too much for a paper punching bolt gun?

Ive gotten some decent groups out of it (around .350) but they are very inconsistent, and some groups have a lot of horizontal stringing, and i wonder if the .004 neck tension could be the issue?

 

[427Cobra]

Re: problems with too much neck tension

I use a 290 bushing, works good Win 7-08 lasts long time

 

[mdmp5]

Re: problems with too much neck tension

.004 of neck tension shouldn't be enough to destroy accuracy to a major degree. If you measure the neck tension on a box of lapua brass, about 10% of the cases will yield over .004 NT if you got a bushing to give you .001-.002 NT. For example, I use a 337 bushing for my 308. Most of my cartridges are .338-.339, but I have a few that are .341 to as much as .342. I haven't found any reliable correlation between the thicker, high NT cases and accuracy. However, if you are running something extreme like .008 NT, then yes, you can induce some major runout, since the bullet is prying the mouth open when seating.

 

[Tangodown911]

Re: problems with too much neck tension

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 427Cobra</div><div class="ubbcode-body">I use a 290 bushing, works good Win 7-08 lasts long time </div></div>

Bukakke called it right. I would go .290 also.