PDA

View Full Version : Nose sizing?



sawinredneck
07-20-2017, 07:49 PM
So I've got the NOE sizer and am building up my kit slowly, but this nose sizing is cornfudging me!
I'm using the Lee 309-180rn in my AR-10 and I'd like to get a little more length as I try to work up loads, once it cools off some! Right now I'm having to load them COAL of 2.6" to get them to chamber. PC'd the nose OD is .301-.303", but they catch on the throat with just the nose.
I'm bad, I haven't chamber cast it, and honestly really don't want to, it looks like a nightmare on these things, it's scary!
The smallest nose sizer NOE sells is .298", that's .003-.005", I'm not thinking, from seeing the leade grooves in a slug, it's going to be enough to matter? I know, I know, "Slug it!"

RoyEllis
07-20-2017, 08:32 PM
If you want accuracy, then put in the work to do it right the first time. Not trying to be an **** to you, so don't be upset......it's oft repeated with cast that "fit is king" and you can't get there "by guess & by golly". AR's are dead simple to chamber cast, with a few tools the barrel can be removed, cast made then reinstalled. You can slug the bore at the same time, giving yourself a complete picture of what you have and what direction to take.

sawinredneck
07-20-2017, 09:09 PM
If you want accuracy, then put in the work to do it right the first time. Not trying to be an **** to you, so don't be upset......it's oft repeated with cast that "fit is king" and you can't get there "by guess & by golly". AR's are dead simple to chamber cast, with a few tools the barrel can be removed, cast made then reinstalled. You can slug the bore at the same time, giving yourself a complete picture of what you have and what direction to take.

I'm not taking you as anything but helpful! I know I'm my own worst enemy on this!
Honestly, I'm not all that serious about accuracy with these rounds, this is just plinking fodder for me. If I want to hunt or chase bullseyes I'll probably go with j-words. But as is I have a 1x Vortex red dot/scope, miserable eyesight, and am honestly, not that good of a shot with anything other than my Ruger 10/22! Only then because I've had it over 32yrs and shot it a lot! Old dog, new tricks!
So I'm not trying to chase any magical dragon or anything, I just want to semi-replicate the surplus ball ammo (147grn 7.62x51) that I normally shoot. POI, POA, without adjusting anything.

Bama
07-20-2017, 10:23 PM
I run that same bullet in a RockRiver. I had to size to .300 in order to feed reliably and I size all the way to the drive bands. You should be pleasantly surprised with accuracy but you may have to add copper at the higher velocities.

gpidaho
07-20-2017, 11:06 PM
sawinredneck: I have a new Savage model 10 tactical rifle in 308Win. So far (very early) in testing it likes the same bullet that you're using. The Lee .309-180-RN I have the NOE nose sizing bushings in .298, .299, 300, 301 and 302. I've found a nice side fit with the noses sized .301 and if I'm powder coating I start with the .299 bushing then coat and resize to .301. You don't have to do a chamber cast to find the right size. Just make a dummy round and paint the bullet you think might work with a Bic sharpie. until you find the size that leaves small (very small) marks from the rifling indented in the nose and you have the nose part figured out. Then find the I.D of the neck of a fired round and you have the size your bands need to be sized to. This nose sizing thing can take a lot of effort. If you don't enjoy the time spent tinkering it can become a chore. So, if you're just looking for plinking rounds skip that part and just concentrate on getting the bands sized right. Gp