Enough neck tension?

[Mr.Snerdly]

I loaded up the Sierra 70 grain bullets for the 243. Seating them .050 off the lands only gives .1515" in the case. I know someone said the old rule about the depth being as deep as the caliber is not necessary but that is quite a little ways off. I would like to seat it to .020 but I am pretty sure that would be too little bullet in the neck. Any advice appreciated.

This measurement may be off some since I did it with the unreliable digital calipers but I measured several times and averaged them. I simply have to invest in some micrometers to be comfortable with my measurements.

[Ted_Feasel]

I loaded up the Sierra 70 grain bullets for the 243. Seating them .050 off the lands only gives .1515" in the case. I know someone said the old rule about the depth being as deep as the caliber is not necessary but that is quite a little ways off. I would like to seat it to .020 but I am pretty sure that would be too little bullet in the neck. Any advice appreciated.

This measurement may be off some since I did it with the unreliable digital calipers but I measured several times and averaged them. I simply have to invest in some micrometers to be comfortable with my measurements.What I've done and seems to work is, when I'm seating pills, if I feel that I'm getting a wide range of pressures to seat them, then I put in the next smallest neck bushing and so far that has always had a positive outcome on neck tension, i use the k&m arbor press with the Guage that shows how much force your exerting and when i use that neck bushing method of going to next size down i get a very consistent forces exertion. Make sure you are taking care to get your chambfering done squarely and the same amount of brass removed, same angel of chambfer etc.. thats just my approach, im sure there are many other valid and probably better approaches.

Sent from my SM-N975U using Tapatalk

[Robinhood]

Have you tried them at book length yet? 2.625 for the smk & hp. 2.670 for the blitzking.

[Mr.Snerdly]

^^^Is that information available anywhere other than the Sierra reloading manual? I hate to have to buy another reloading manual. I have 2 the way it is.

[Ted_Feasel]

Have you tried them at book length yet? 2.625 for the smk & hp. 2.670 for the blitzking.Almost all my different cals I've found what I wanted at suggested OAL...certainly makes it easier:)

Sent from my SM-N975U using Tapatalk

[Robinhood]

^^^Is that information available anywhere other than the Sierra reloading manual? I hate to have to buy another reloading manual. I have 2 the way it is.

Since you are using Sierra bullets and the data is tested using the exact bullet you have, I think it is a safe bet. If you results are vastly different you could try pushing them out.

[243winxb]

https://www.accurateshooter.com/cartridge-guides/243win/

See the Sierra load map link.

[Mr.Snerdly]

^^^That's a good site. I bookmarked it. Thank you.

[Mr.Snerdly]

Have you tried them at book length yet? 2.625 for the smk & hp. 2.670 for the blitzking.


I can't hardly believe this. I was going to take your advice and seat them to the dimension you gave. I figured I would have to seat them considerably deeper but to my surprise they are almost the dimension you gave. Naturally, they are not EXACTLY the same, some were .0005" less, some others were a few thousandths more but this could be due to the inaccuracy of the digital calipers and I suppose even no matter how you seat them there might be a very slight variation, say .002" unless you get extremely specialized, expensive equipment.

[Ted_Feasel]

I can't hardly believe this. I was going to take your advice and seat them to the dimension you gave. I figured I would have to seat them considerably deeper but to my surprise they are almost the dimension you gave. Naturally, they are not EXACTLY the same, some were .0005" less, some others were a few thousandths more but this could be due to the inaccuracy of the digital calipers and I suppose even no matter how you seat them there might be a very slight variation, say .002" unless you get extremely specialized, expensive equipment.Its a pain in the butt, but I seat by the ogive sorting and measuring all 100 1st, doing this way the OAL is always varying. I just use OAL as a generic number on my lables

Sent from my SM-N975U using Tapatalk

[Robinhood]

I can't hardly believe this. I was going to take your advice and seat them to the dimension you gave. I figured I would have to seat them considerably deeper but to my surprise they are almost the dimension you gave. Naturally, they are not EXACTLY the same, some were .0005" less, some others were a few thousandths more but this could be due to the inaccuracy of the digital calipers and I suppose even no matter how you seat them there might be a very slight variation, say .002" unless you get extremely specialized, expensive equipment.

I have heard it mentioned on this forum several times about how people don't trust digital calipers. I would not discount them because they were digital, if anything because they were cheap crap. But there are several manufactures that make quality digital calipers. I never used them that much mostly because I am paying for them.

[Ted_Feasel]

I have heard it mentioned on this forum several times about how people don't trust digital calipers. I would not discount them because they were digital, if anything because they were cheap crap. But there are several manufactures that make quality digital calipers. I never used them that much mostly because I am paying for them.I have a set i trust implicitly. Ive compared them to my mitutoyos 100s of time and they have always been accurate. Ive found more often than not, its a burr or something virtually unnoticeable that causes reading fluctuations, a good example is on a AR build before i get the buffer system and gas system properly weighted and tuned, the extractor marks are enough to change your reading on case length just depending on where you place the case on the calipers. Not saying thats the issue but when your measuring
.001 and less, it doesn't take much

Sent from my SM-N975U using Tapatalk